US20210179713A1 - Anti-pd-1 antibodies, activatable anti-pd-1 antibodies, and methods of use thereof - Google Patents

Abstract

The invention relates generally to antibodies that specifically bind programmed cell death protein 1 (PD-1), activatable antibodies that specifically bind to PD-1 and methods of making and using these anti-PD-1 antibodies and anti-PD-1 activatable antibodies in a variety of therapeutic, diagnostic and prophylactic indications.

Description

RELATED APPLICATIONS
• This application is a divisional of U.S. application Ser. No. 15/209,385, filed on Jul. 13, 2016, which claims the benefit of U.S. Provisional Application No. 62/191,902, filed Jul. 13, 2015; U.S. Provisional Application No. 62/205,825, filed Aug. 17, 2015; U.S. Provisional Application No. 62/295,314, filed Feb. 15, 2016; U.S. Provisional Application No. 62/323,543, filed Apr. 15, 2016 and U.S. Provisional Application No. 62/333,629, filed May 9, 2016; the contents of each of which are incorporated herein by reference in their entirety.
DESCRIPTION OF THE TEXT FILE SUBMITTED ELECTRONICALLY
• The contents of the text file submitted electronically herewith are incorporated herein by reference in their entirety: A computer readable format copy of the Sequence Listing (filename: CYTM_044_001_US_SubSeqList_ST25.txt, dated recorded Mar. 21, 2019, file size 1.37 MB) in U.S. patent application Ser. No. 15/209,385.
FIELD OF THE INVENTION
• The invention relates generally to antibodies that specifically bind programmed cell death protein 1 (PD-1), activatable antibodies that specifically bind to PD-1 and methods of making and using these anti-PD-1 antibodies and anti-PD-1 activatable antibodies in a variety of therapeutic, diagnostic and prophylactic indications.
BACKGROUND OF THE INVENTION
• Antibody-based therapies have proven effective treatments for several diseases but in some cases, toxicities due to broad target expression have limited their therapeutic effectiveness. In addition, antibody-based therapeutics have exhibited other limitations such as rapid clearance from the circulation following administration.
• Under conditions of chronic stimulation, T cells upregulate and sustain expression of the inhibitory receptor PD-1 to negatively regulate the quality and magnitude of T cell responses. The primary ligand for PD-1, PD-L1 is upregulated on many tumor cells and has been associated with inhibition of anti-tumor T-cell immunity via its engagement of PD-1 on tumor-infiltrating T cells. Clinical trials have confirmed the capacity of antibody blockade of either PD-1 or PD-L1 to restore the activity of durable tumor-specific immunity in patients across multiple tumor types. (Herbst et al, 2014; Lipson et al, 2015). However, because similar mechanisms control anti-tumor immunity and self-tolerance, systemic delivery of these checkpoint-targeted therapies can also induce systemic autoimmunity that can be exacerbated with combination treatments; such as nivolumab or pembrolizumab (anti-PD-1) and ipilimumab (anti-CTLA4). New approaches are therefore needed that provide anti-tumor activity without deregulating systemic immunity.
• In the realm of small molecule therapeutics, strategies have been developed to provide prodrugs of an active chemical entity. Such prodrugs are administered in a relatively inactive (or significantly less active) form. Once administered, the prodrug is metabolized in vivo into the active compound. Such prodrug strategies can provide for increased selectivity of the drug for its intended target and for a reduction of adverse effects.
• Accordingly, there is a continued need in the field of antibody-based therapeutics for antibodies that mimic the desirable characteristics of the small molecule prodrug.
SUMMARY OF THE INVENTION
• The disclosure provides antibodies or antigen-binding fragments thereof that specifically bind programmed cell death protein 1 (PD-1), also known as CD279, SLEB2, and/or hSLE1. The use of the term “PD-1” is intended to cover any variation thereof, such as, by way of non-limiting example, PD1 and/or PD 1, all variations are used herein interchangeably. Aberrant expression and/or activity of PD-1 and PD-1-related signaling has been implicated in the pathogenesis of many diseases and disorders, such as cancer.
• The present invention provides monoclonal antibodies (mAbs), activatable antibodies, and antigen-binding fragments thereof that specifically bind PD-1.
• In some embodiments, the antibody includes an antibody or antigen-binding fragment thereof that specifically binds PD-1. In some embodiments, the antibody or antigen-binding fragment thereof that binds PD-1 is a monoclonal antibody, domain antibody, single chain, Fab fragment, a F(ab′)₂ fragment, a scFv, a scAb, a dAb, a single domain heavy chain antibody, or a single domain light chain antibody. In some embodiments, such an antibody or antigen-binding fragment thereof that binds PD-1 is a mouse, other rodent, chimeric, humanized or fully human monoclonal antibody.
• In some embodiments, the antibody includes an isolated antibody or antigen binding fragment thereof (AB) that specifically binds to mammalian PD-1, wherein the AB has one or more of the characteristics selected from the group consisting of: (a) the AB inhibits binding of mammalian PD-1 to mammalian PDL1 with an EC₅₀ value less than 5 nM; (b) the AB inhibits binding of mammalian PD-1 to mammalian PDL2 with an EC₅₀ value less than 5 nM; and (c) the AB specifically binds to human PD-1 and cynomolgus monkey PD-1.
• In some embodiments, the antibody specifically binds to the mammalian PD-1 with a dissociation constant of 0.01 nM to 5 nM, 0.05 nM to 5 nM, 0.1 nM to 5 nM, 0.2 nM to 5 nM, 0.3 nM to 5 nM, 0.4 nM to 5 nM, 0.5 nM to 5 nM, 0.75 nM to 5 nM, 1 nM to 5 nM, 2 nM to 5 nM, 0.01 nM to 2 nM, 0.05 nM to 2 nM, 0.1 nM to 2 nM, 0.2 nM to 2 nM, 0.3 nM to 2 nM, 0.4 nM to 2 nM, 0.5 nM to 2 nM, 0.75 nM to 1 nM, 1 nM to 2 nM, 0.01 nM to 1 nM, 0.05 nM to 1 nM, 0.1 nM to 1 nM, 0.2 nM to 1 nM, 0.3 nM to 1 nM, 0.4 nM to 1 nM, 0.5 nM to 1 nM, 0.75 nM to 1 nM, 0.01 nM to 0.75 nM, 0.05 nM to 0.75 nM, 0.1 nM to 0.75 nM, 0.2 nM to 0.75 nM, 0.3 nM to 0.75 nM, 0.4 nM to 0.75 nM, 0.5 nM to 0.75 nM, 0.01 nM to 0.5 nM, 0.05 nM to 0.5 nM, 0.1 nM to 0.5 nM, 0.2 nM to 0.5 nM, 0.3 nM to 0.5 nM, 0.4 nM to 0.5 nM, 0.01 nM to 0.4 nM, 0.05 nM to 0.4 nM, 0.1 nM to 0.4 nM, 0.2 nM to 0.4 nM, 0.3 nM to 0.4 nM, 0.01 nM to 0.3 nM, 0.05 nM to 0.3 nM, 0.1 nM to 0.3 nM, 0.2 nM to 0.3 nM, 0.01 nM to 0.2 nM, 0.05 nM to 0.2 nM, 0.1 nM to 0.2 nM, 0.01 nM to 0.1 nM, 0.05 nM to 0.1 nM, or 0.01 nM to 0.05 nM.
• In some embodiments, the mammalian PD-1 is selected from the group consisting of a human PD-1 and a cynomolgus monkey PD-1. In some embodiments, the mammalian PD-1 is a murine PD-1. In some embodiments, the antibody specifically binds to human PD-1 or cynomolgus monkey PD-1 with a dissociation constant of less than or equal to 1 nM. In some embodiments, the mammalian PD-1 is a human PD-1.
• In some embodiments, the antibody or antigen binding fragment thereof specifically binds to the mammalian PD-1 with a dissociation constant is less than or equal to 0.01 nM, less than or equal to 0.05 nM, less than or equal to 0.1 nM, less than or equal to 0.2 nM, less than or equal to 0.3 nM, less than or equal to 0.4 nM, less than or equal to 0.5 nM, less than or equal to 0.75 nM, and less than or equal to 1 nM.
• In some embodiments, the antibody has one or more of the characteristics selected from the group consisting of: (a) the AB specifically binds human PD-1 and cynomolgus monkey PD-1; (b) the AB inhibits binding of human PDL1 and human PDL2 to human PD-1; (c) the AB inhibits binding of cynomolgus monkey PDL1 and cynomolgus monkey PDL2 to cynomolgus monkey PD-1; (d) the AB specifically binds to murine PD-1; and (e) the AB inhibits binding of murine PDL1 and murine PDL2 to murine PD-1.
• In some embodiments, the antibody blocks the ability of a natural ligand to bind to the mammalian PDL1 with an EC₅₀ of 0.1 nM to 10 nM, 0.1 nM to 5 nM, 0.1 nM to 3 nM, 0.1 nM to 2 nM, 0.1 nM to 1 nM, 0.1 nM to 0.5 nM, 0.1 nM to 0.25 nM, 0.25 nM to 10 nM, 0.25 nM to 5 nM, 0.25 nM to 3 nM, 0.25 nM to 2 nM, 0.25 nM to 1 nM, 0.25 nM to 0.5 nM, 0.5 nM to 10 nM, 0.5 nM to 5 nM, 0.5 nM to 3 nM, 0.5 nM to 2 nM, 0.5 nM to 1 nM, 1 nM to 10 nM, 1 nM to 5 nM, 1 nM to 3 nM, 1 nM to 2 nM, 2 nM to 10 nM, 2 nM to 5 nM, 2 nM to 3 nM, 3 nM to 10 nM, 3 nM to 5 nM, or 5 nM to 10 nM. In some embodiments, the natural ligand is a mammalian PDL1 or a mammalian PDL2. In some embodiments, the natural ligand is selected from the group consisting of: a human PDL1, a human PDL2, a cynomolgus monkey PDL1, and a cynomolgus monkey PDL2. In some embodiments, the natural ligand is a murine PDL1 or a murine PDL2.
• In some embodiments, the antibody blocks the ability of a natural ligand to bind to the mammalian PDL1 with an EC₅₀ of less than or equal to 0.1 nM, less than or equal to 0.25 nM, less than or equal to 0.5 nM, less than or equal to 1 nM, less than or equal to 2 nM, less than or equal to 3 nM, less than or equal to 4 nM, less than or equal to 5 nM or less than or equal to 10 nM.
• In some embodiments, the anti-PD-1 antibody includes a heavy chain that comprises or is derived from an amino acid sequence selected from the group consisting of SEQ ID NO: 1, 5, 9, 13, 17, 21, 23, 25, 27, 29, 31, 33, 35, and 37, and a light chain that comprises or is derived from an amino acid sequence selected from the group consisting of SEQ ID NO: 3, 7, 11, 15, 19, 39, 41, 43, 45, 47, 49, 51, 53, 55, 57, and 59.
• In some embodiments, the anti-PD-1 antibody includes a heavy chain that comprises or is derived from an amino acid sequence selected from the group consisting of SEQ ID NO: 21, 23, 25, 27, 29, 31, 33, 35, and 37, and a light chain that comprises or is derived from an amino acid sequence selected from the group consisting of SEQ ID NO: 39, 41, 43, 45, 47, 49, 51, 53, 55, 57, and 59.
• In some embodiments, the anti-PD-1 antibody includes a heavy chain that comprises or is derived from amino acid sequence SEQ ID NO: 21. In some embodiments, the anti-PD-1 antibody includes a light chain that comprises or is derived from amino acid sequence SEQ ID NO: 45 or SEQ ID NO: 47. In some embodiments, the anti-PD-1 antibody includes a heavy chain that comprises or is derived from amino acid sequence SEQ ID NO: 21 and a light chain that comprises or is derived from amino acid sequence SEQ ID NO: 45 or SEQ ID NO: 47. In some embodiments, the anti-PD-1 antibody includes a heavy chain that comprises or is derived from amino acid sequence SEQ ID NO: 21 and a light chain that comprises or is derived from amino acid sequence SEQ ID NO: 45. In some embodiments, the anti-PD-1 antibody includes a heavy chain that comprises or is derived from amino acid sequence SEQ ID NO: 21 and a light chain that comprises or is derived from amino acid sequence SEQ ID NO: 47.
• In some embodiments, the anti-PD-1 antibody includes the combination of the complementarity determining region (CDR) sequences of the heavy chain amino acid sequence of SEQ ID NO: 21. In some embodiments, the anti-PD-1 antibody includes the combination of the CDR sequences of the light chain amino acid sequence of SEQ ID NO: 45 or of SEQ ID NO: 47. In some embodiments, the anti-PD-1 antibody includes a combination of the CDR sequences of the heavy chain amino acid sequence of SEQ ID NO: 21, and the CDR sequences of the light chain amino acid sequence of SEQ ID NO: 45 or 47. In some embodiments, the anti-PD-1 antibody includes a combination of the CDR sequences of the heavy chain amino acid sequence of SEQ ID NO: 21, and the CDR sequences of the light chain amino acid sequence of SEQ ID NO: 45. In some embodiments, the anti-PD-1 antibody includes a combination of the CDR sequences of the heavy chain amino acid sequence of SEQ ID NO: 21, and the CDR sequences of the light chain amino acid sequence of SEQ ID NO: 47.
• In some embodiments, the anti-PD-1 antibody includes: (a) a variable heavy chain complementarity determining region 1 (VH CDR1) comprising an amino acid sequence selected from the group consisting of SEQ ID NOs: 653-657; (b) a variable heavy chain complementarity determining region 2 (VH CDR2) comprising an amino acid sequence selected from the group consisting of SEQ ID NOs: 658-663; (c) a variable heavy chain complementarity determining region 3 (VH CDR3) comprising an amino acid sequence selected from the group consisting of SEQ ID NOs: 664-668; (d) a variable light chain complementarity determining region 1 (VL CDR1) comprising an amino acid sequence selected from the group consisting of SEQ ID NOs: 669-677; (e) a variable light chain complementarity determining region 2 (VL CDR2) comprising an amino acid sequence selected from the group consisting of SEQ ID NOs: 678-682; and (f) variable light chain complementarity determining region 3 (VL CDR3) comprising an amino acid sequence selected from the group consisting of SEQ ID NOs: 683-687.
• In some embodiments, the anti-PD-1 antibody includes a combination of a variable heavy chain complementarity determining region 1 (VH CDR1, also referred to herein as CDRH1) sequence, a variable heavy chain complementarity determining region 2 (VH CDR2, also referred to herein as CDRH2) sequence, and a variable heavy chain complementarity determining region 3 (VH CDR3, also referred to herein as CDRH3) sequence, wherein the VH CDR1 sequence comprises GFTFSGYAMS (SEQ ID NO: 653); the VH CDR2 sequence comprises YISNSGGNAH (SEQ ID NO: 658); and the VH CDR3 sequence comprises EDYGTSPFVY (SEQ ID NO: 664).
• In some embodiments, the anti-PD-1 antibody includes a combination of a variable light chain complementarity determining region 1 (VL CDR1, also referred to herein as CDRL1) sequence, a variable light chain complementarity determining region 2 (VL CDR2, also referred to herein as CDRL2) sequence, and a variable light chain complementarity determining region 3 (VL CDR3, also referred to herein as CDRL3) sequence, wherein the VL CDR1 sequence comprises RASESVDSYGISFMN (SEQ ID NO: 675) or RASESVDAYGISFMN (SEQ ID NO:676); the VL CDR2 sequence comprises AASNQGS (SEQ ID NO: 678); and the VL CDR3 sequence comprises QQSKDVPWT (SEQ ID NO: 683). In some embodiments, the anti-PD-1 antibody includes a combination of a VL CDR1 sequence, a VL CDR2 sequence, and a VL CDR3 sequence, wherein the VL CDR1 sequence comprises RASESVDSYGISFMN (SEQ ID NO: 675); the VL CDR2 sequence comprises AASNQGS (SEQ ID NO: 678); and the VL CDR3 sequence comprises QQSKDVPWT (SEQ ID NO: 683). In some embodiments, the anti-PD-1 antibody includes a combination of a VL CDR1 sequence, a VL CDR2 sequence, and a VL CDR3 sequence, wherein the VL CDR1 sequence comprises RASESVDAYGISFMN (SEQ ID NO:676); the VL CDR2 sequence comprises AASNQGS (SEQ ID NO: 678); and the VL CDR3 sequence comprises QQSKDVPWT (SEQ ID NO: 683).
• In some embodiments, the anti-PD-1 antibody includes a combination of a VH CDR1 sequence, a VH CDR2 sequence, a VH CDR3 sequence, a VL CDR1 sequence, a VL CDR2 sequence, and a VL CDR3 sequence, wherein the VH CDR1 sequence comprises GFTFSGYAMS (SEQ ID NO: 653); the VH CDR2 sequence comprises YISNSGGNAH (SEQ ID NO: 658); and the VH CDR3 sequence comprises EDYGTSPFVY (SEQ ID NO: 664); the VL CDR1 sequence comprises RASESVDSYGISFMN (SEQ ID NO: 675) or RASESVDAYGISFMN (SEQ ID NO:676); the VL CDR2 sequence comprises AASNQGS (SEQ ID NO: 678); and the VL CDR3 sequence comprises QQSKDVPWT (SEQ ID NO: 683). In some embodiments, the anti-PD-1 antibody includes a combination of a VH CDR1 sequence, a VH CDR2 sequence, a VH CDR3 sequence, a VL CDR1 sequence, a VL CDR2 sequence, and a VL CDR3 sequence, wherein the VH CDR1 sequence comprises GFTFSGYAMS (SEQ ID NO: 653); the VH CDR2 sequence comprises YISNSGGNAH (SEQ ID NO: 658); and the VH CDR3 sequence comprises EDYGTSPFVY (SEQ ID NO: 664); the VL CDR1 sequence comprises RASESVDSYGISFMN (SEQ ID NO: 675); the VL CDR2 sequence comprises AASNQGS (SEQ ID NO: 678); and the VL CDR3 sequence comprises QQSKDVPWT (SEQ ID NO: 683). In some embodiments, the anti-PD-1 antibody includes a combination of a VH CDR1 sequence, a VH CDR2 sequence, a VH CDR3 sequence, a VL CDR1 sequence, a VL CDR2 sequence, and a VL CDR3 sequence, wherein the VH CDR1 sequence comprises GFTFSGYAMS (SEQ ID NO: 653); the VH CDR2 sequence comprises YISNSGGNAH (SEQ ID NO: 658); and the VH CDR3 sequence comprises EDYGTSPFVY (SEQ ID NO: 664); the VL CDR1 sequence comprises RASESVDAYGISFMN (SEQ ID NO:676); the VL CDR2 sequence comprises AASNQGS (SEQ ID NO: 678); and the VL CDR3 sequence comprises QQSKDVPWT (SEQ ID NO: 683).
• In some embodiments, the anti-PD-1 antibody includes a heavy chain that comprises or is derived from the amino acid sequence of SEQ ID NO: 1346, and a light chain that comprises or is derived from the amino acid sequence of SEQ ID NO: 626.
• In some embodiments, the anti-PD-1 antibody includes a heavy chain that comprises or is derived from the amino acid sequence of SEQ ID NO: 1514, and a light chain that comprises or is derived from the amino acid sequence of SEQ ID NO: 638.
• In some embodiments, the anti-PD-1 antibody includes the combination of the complementarity determining region (CDR) sequences of the heavy chain amino acid sequence of SEQ ID NO: 1346. In some embodiments, the anti-PD-1 antibody includes the combination of the CDR sequences of the light chain amino acid sequence of SEQ ID NO: 626. In some embodiments, the anti-PD-1 antibody includes a combination of the CDR sequences of the heavy chain amino acid sequence of SEQ ID NO: 1346, and the CDR sequences of the light chain amino acid sequence of SEQ ID NO: 626.
• In some embodiments, the anti-PD-1 antibody includes a combination of a variable heavy chain complementarity determining region 1 (VH CDR1, also referred to herein as CDRH1) sequence, a variable heavy chain complementarity determining region 2 (VH CDR2, also referred to herein as CDRH2) sequence, and a variable heavy chain complementarity determining region 3 (VH CDR3, also referred to herein as CDRH3) sequence, wherein the VH CDR1 sequence comprises GITFSNSG (SEQ ID NO: 1705); the VH CDR2 sequence comprises IWYDGSKR (SEQ ID NO: 1706); and the VH CDR3 sequence comprises TNDDY (SEQ ID NO: 1707).
• In some embodiments, the anti-PD-1 antibody includes a combination of a variable light chain complementarity determining region 1 (VL CDR1, also referred to herein as CDRL1) sequence, a variable light chain complementarity determining region 2 (VL CDR2, also referred to herein as CDRL2) sequence, and a variable light chain complementarity determining region 3 (VL CDR3, also referred to herein as CDRL3) sequence, wherein the VL CDR1 sequence comprises QSVSSY (SEQ ID NO: 1708); the VL CDR2 sequence comprises DAS (SEQ ID NO: 1709); and the VL CDR3 sequence comprises QQSSNWPRT (SEQ ID NO: 1710).
• In some embodiments, the anti-PD-1 antibody includes a combination of a VH CDR1 sequence, a VH CDR2 sequence, a VH CDR3 sequence, a VL CDR1 sequence, a VL CDR2 sequence, and a VL CDR3 sequence, wherein the VH CDR1 sequence comprises GITFSNSG (SEQ ID NO: 1705); the VH CDR2 sequence comprises IWYDGSKR (SEQ ID NO: 1706); the VH CDR3 sequence comprises TNDDY (SEQ ID NO: 1707); the VL CDR1 sequence comprises QSVSSY (SEQ ID NO: 1708); the VL CDR2 sequence comprises DAS (SEQ ID NO: 1709); and the VL CDR3 sequence comprises QQSSNWPRT (SEQ ID NO: 1710).
• In some embodiments, the anti-PD-1 antibody includes the combination of the complementarity determining region (CDR) sequences of the heavy chain amino acid sequence of SEQ ID NO: 1514. In some embodiments, the anti-PD-1 antibody includes the combination of the CDR sequences of the light chain amino acid sequence of SEQ ID NO: 638. In some embodiments, the anti-PD-1 antibody includes a combination of the CDR sequences of the heavy chain amino acid sequence of SEQ ID NO: 1514, and the CDR sequences of the light chain amino acid sequence of SEQ ID NO: 638.
• In some embodiments, the anti-PD-1 antibody includes a combination of a variable heavy chain complementarity determining region 1 (VH CDR1, also referred to herein as CDRH1) sequence, a variable heavy chain complementarity determining region 2 (VH CDR2, also referred to herein as CDRH2) sequence, and a variable heavy chain complementarity determining region 3 (VH CDR3, also referred to herein as CDRH3) sequence, wherein the VH CDR1 sequence comprises GYTFTNYY (SEQ ID NO: 1711); the VH CDR2 sequence comprises INPSNGGT (SEQ ID NO: 1712); and the VH CDR3 sequence comprises RRDYRFDMGFDY (SEQ ID NO: 1713).
• In some embodiments, the anti-PD-1 antibody includes a combination of a variable light chain complementarity determining region 1 (VL CDR1, also referred to herein as CDRL1) sequence, a variable light chain complementarity determining region 2 (VL CDR2, also referred to herein as CDRL2) sequence, and a variable light chain complementarity determining region 3 (VL CDR3, also referred to herein as CDRL3) sequence, wherein the VL CDR1 sequence comprises KGVSTSGYSY (SEQ ID NO: 1714); the VL CDR2 sequence comprises LAS (SEQ ID NO: 1715); and the VL CDR3 sequence comprises QHSRDLPLT (SEQ ID NO: 1716).
• In some embodiments, the anti-PD-1 antibody includes a combination of a VH CDR1 sequence, a VH CDR2 sequence, a VH CDR3 sequence, a VL CDR1 sequence, a VL CDR2 sequence, and a VL CDR3 sequence, wherein the VH CDR1 sequence comprises GYTFTNYY (SEQ ID NO: 1711); the VH CDR2 sequence comprises INPSNGGT (SEQ ID NO: 1712); the VH CDR3 sequence comprises RRDYRFDMGFDY (SEQ ID NO: 1713); the VL CDR1 sequence comprises KGVSTSGYSY (SEQ ID NO: 1714); the VL CDR2 sequence comprises LAS (SEQ ID NO: 1715); and the VL CDR3 sequence comprises QHSRDLPLT (SEQ ID NO: 1716).
• In some embodiments, the antibody comprises a heavy chain amino acid sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to an amino acid sequence selected from the group consisting of SEQ ID NO: 1, 5, 9, 13, 17, 21, 23, 25, 27, 29, 31, 33, 35, and 37. In some embodiments, the antibody comprises a light chain amino acid that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to an amino acid sequence selected from the group consisting of SEQ ID NO: 3, 7, 11, 15, 19, 39, 41, 43, 45, 47, 49, 51, 53, 55, 57, and 59. In some embodiments, the antibody comprises a heavy chain amino acid sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to an amino acid sequence selected from the group consisting of SEQ ID NO: 1, 5, 9, 13, 17, 21, 23, 25, 27, 29, 31, 33, 35, and 37, and a light chain amino acid that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to an amino acid sequence selected from the group consisting of SEQ ID NO: 3, 7, 11, 15, 19, 39, 41, 43, 45, 47, 49, 51, 53, 55, 57, and 59.
• In some embodiments, the antibody comprises a heavy chain amino acid sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to an amino acid sequence selected from the group consisting of SEQ ID NO: 21, 23, 25, 27, 29, 31, 33, 35, and 37. In some embodiments, the antibody comprises a light chain amino acid that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to an amino acid sequence selected from the group consisting of SEQ ID NO: 39, 41, 43, 45, 47, 49, 51, 53, 55, 57, and 59. In some embodiments, the antibody comprises a heavy chain amino acid sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to an amino acid sequence selected from the group consisting of SEQ ID NO: 21, 23, 25, 27, 29, 31, 33, 35, and 37, and a light chain amino acid that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to an amino acid sequence selected from the group consisting of SEQ ID NO: 39, 41, 43, 45, 47, 49, 51, 53, 55, 57, and 59. In some embodiments, the anti-PD-1 antibody includes a heavy chain sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to the amino acid sequence of SEQ ID NO: 21, and a light chain sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to the amino acid sequence of SEQ ID NO: 45 or SEQ ID NO: 47. In some embodiments, the anti-PD-1 antibody includes a heavy chain sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to the amino acid sequence of SEQ ID NO: 21, and a light chain sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to the amino acid sequence of SEQ ID NO: 45. In some embodiments, the anti-PD-1 antibody includes a heavy chain sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to the amino acid sequence of SEQ ID NO: 21, and a light chain sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to the amino acid sequence of SEQ ID NO: 47.
• In some embodiments, the anti-PD-1 antibody includes a heavy chain amino acid sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to the amino acid sequence of SEQ ID NO: 1346, and a light chain amino acid sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to the amino acid sequence of SEQ ID NO: 626.
• In some embodiments, the anti-PD-1 antibody includes a heavy chain amino acid sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to the amino acid sequence of SEQ ID NO: 1514, and a light chain amino acid sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to the amino acid sequence of SEQ ID NO: 638.
• In some embodiments, the antibody comprises a combination of a variable heavy chain complementarity determining region 1 (VH CDR1, also referred to herein as CDRH1) sequence, a variable heavy chain complementarity determining region 2 (VH CDR2, also referred to herein as CDRH2) sequence, a variable heavy chain complementarity determining region 3 (VH CDR3, also referred to herein as CDRH3) sequence, a variable light chain complementarity determining region 1 (VL CDR1, also referred to herein as CDRL1) sequence, a variable light chain complementarity determining region 2 (VL CDR2, also referred to herein as CDRL2) sequence, and a variable light chain complementarity determining region 3 (VL CDR3, also referred to herein as CDRL3) sequence, wherein at least one CDR sequence is selected from the group consisting of a VH CDR1 sequence shown in Table 8; a VH CDR2 sequence shown in Table 8; a VH CDR3 sequence shown in Table 8; a VL CDR1 sequence shown in Table 8; a VL CDR2 sequence shown in Table 8; and a VL CDR3 sequence shown in Table 8.
• In some embodiments, the antibody comprises a combination of a VH CDR1 sequence, a VH CDR2 sequence, a VH CDR3 sequence, a VL CDR1 sequence, a VL CDR2 sequence, and a VL CDR3 sequence, wherein at least one CDR sequence is selected from the group consisting of a VH CDR1 sequence that includes a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to a VH CDR1 sequence shown in Table 8; a VH CD2 sequence that includes a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to a VH CDR2 sequence shown in Table 8; a VH CDR3 sequence that includes a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to a VH CDR3 sequence shown in Table 8; a VL CDR1 sequence that includes a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to a VL CDR1 sequence shown in Table 8; a VL CDR2 sequence that includes a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to a VL CDR2 sequence shown in Table 8; and a VL CDR3 sequence that includes a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to a VL CDR3 sequence shown in Table 8.
• In some embodiments, the antibody comprises a heavy chain that comprises a combination of a VH CDR1 sequence, a VH CDR2 sequence, and a VH CDR3 sequence, wherein the combination is a combination of the three heavy chain CDR sequences (VH CDR1, VH CDR2, VH CDR3) shown in a single row in Table 8.
• In some embodiments, the antibody comprises a light chain that comprises a combination of a VL CDR1 sequence, a VL CDR2 sequence, and a VL CDR3 sequence, wherein the combination is a combination of the three light chain CDR sequences (VL CDR1, VL CDR2, VL CDR3) shown in a single row in Table 8.
• In some embodiments, the antibody comprises a combination of a VH CDR1 sequence, a VH CDR2 sequence, a VH CDR3 sequence shown in a single row in Table 8, and a VL CDR1 sequence, a VL CDR2 sequence, and a VL CDR3 sequence shown in a single row in Table 8.
• In some embodiments, the antibody comprises a combination of a VH CDR1 sequence, a VH CDR2 sequence, a VH CDR3 sequence shown in a single row in Table 8, and a VL CDR1 sequence, a VL CDR2 sequence, and a VL CDR3 sequence shown in a single row in Table 8, wherein each CDR sequence in the combination comprises a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to the corresponding VH CDR sequence shown in a single row in Table 8 and the corresponding VL CDR shown in a single row in Table 8.
• In some embodiments, the antibody comprises a heavy chain that comprises a combination of a VH CDR1 sequence, a VH CDR2 sequence, and a VH CDR3 sequence, wherein each CDR sequence in the combination comprises a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to the corresponding CDR sequence in a combination of three heavy chain CDR sequences (VH CDR1, VH CDR2, VH CDR3) shown in a single row in Table 8.
• In some embodiments, the antibody comprises a light chain that comprises a combination of a VL CDR1 sequence, a VL CDR2 sequence, and a VL CDR3 sequence, wherein each CDR sequence in the combination comprises a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to the corresponding CDR sequence in a combination of three light chain CDR sequences (VL CDR1, VL CDR2, VL CDR3) shown in a single row in Table 8.
• In some embodiments, the antibody includes a combination of a VH CDR1 sequence, a VH CDR2 sequence, and a VH CDR3 sequence, wherein the VH CDR1 sequence comprises a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to GITFSNSG (SEQ ID NO: 1705); the VH CDR2 sequence comprises a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to IWYDGSKR (SEQ ID NO: 1706); and the VH CDR3 sequence comprises a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to TNDDY (SEQ ID NO: 1707).
• In some embodiments, the anti-PD-1 antibody includes a combination of a VL CDR1 sequence, a VL CDR2 sequence, and a VL CDR3 sequence, wherein the VL CDR1 sequence comprises a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to QSVSSY (SEQ ID NO: 1708); the VL CDR2 sequence comprises a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to DAS (SEQ ID NO: 1709); and the VL CDR3 sequence comprises a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to QQSSNWPRT (SEQ ID NO: 1710).
• In some embodiments, the anti-PD-1 antibody includes a combination of a VH CDR1 sequence, a VH CDR2 sequence, a VH CDR3 sequence, a VL CDR1 sequence, a VL CDR2 sequence, and a VL CDR3 sequence, wherein the VH CDR1 sequence comprises a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to GITFSNSG (SEQ ID NO: 1705); the VH CDR2 sequence comprises a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to IWYDGSKR (SEQ ID NO: 1706); the VH CDR3 sequence comprises a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to TNDDY (SEQ ID NO: 1707); the VL CDR1 sequence comprises a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to QSVSSY (SEQ ID NO: 1708); the VL CDR2 sequence comprises a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to DAS (SEQ ID NO: 1709); and the VL CDR3 sequence comprises a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to QQSSNWPRT (SEQ ID NO: 1710).
• In some embodiments, the antibody includes a combination of a VH CDR1 sequence, a VH CDR2 sequence, and a VH CDR3 sequence, wherein the VH CDR1 sequence comprises a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to GYTFTNYY (SEQ ID NO: 1711); the VH CDR2 sequence comprises a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to INPSNGGT (SEQ ID NO: 1712); and the VH CDR3 sequence comprises a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to RRDYRFDMGFDY (SEQ ID NO: 1713).
• In some embodiments, the anti-PD-1 antibody includes a combination of a VL CDR1 sequence, a VL CDR2 sequence, and a VL CDR3 sequence, wherein the VL CDR1 sequence comprises a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to KGVSTSGYSY (SEQ ID NO: 1714); the VL CDR2 sequence comprises a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to LAS (SEQ ID NO: 1715); and the VL CDR3 sequence comprises a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to QHSRDLPLT (SEQ ID NO: 1716).
• In some embodiments, the anti-PD-1 antibody includes a combination of a VH CDR1 sequence, a VH CDR2 sequence, a VH CDR3 sequence, a VL CDR1 sequence, a VL CDR2 sequence, and a VL CDR3 sequence, wherein the VH CDR1 sequence comprises a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to GYTFTNYY (SEQ ID NO: 1711); the VH CDR2 sequence comprises a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to INPSNGGT (SEQ ID NO: 1712); the VH CDR3 sequence comprises a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to RRDYRFDMGFDY (SEQ ID NO: 1713); the VL CDR1 sequence comprises a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to KGVSTSGYSY (SEQ ID NO: 1714); the VL CDR2 sequence comprises a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to LAS (SEQ ID NO: 1715); and the VL CDR3 sequence comprises a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to QHSRDLPLT (SEQ ID NO: 1716).
• In some embodiments, the antibody is encoded by a nucleic acid sequence that comprises a nucleic acid sequence encoding a heavy chain amino acid sequence selected from the group consisting of SEQ ID NO: 1, 5, 9, 13, 17, 21, 23, 25, 27, 29, 31, 33, 35, and 37. In some embodiments, the antibody is encoded by a nucleic acid sequence that comprises a nucleic acid sequence encoding a heavy chain amino acid sequence selected from the group consisting of SEQ ID NO: 21, 23, 25, 27, 29, 31, 33, 35, and 37.
• In some embodiments, the antibody is encoded by a nucleic acid sequence that comprises a nucleic acid sequence encoding a light chain amino acid sequence selected from the group consisting of SEQ ID NO: 3, 7, 11, 15, 19, 39, 41, 43, 45, 47, 49, 51, 53, 55, 57, and 59. In some embodiments, the antibody is encoded by a nucleic acid sequence that comprises a nucleic acid sequence encoding a light chain amino acid sequence selected from the group consisting of SEQ ID NO: 39, 41, 43, 45, 47, 49, 51, 53, 55, 57, and 59.
• In some embodiments, the antibody is encoded by a nucleic acid sequence that comprises a nucleic acid sequence encoding a heavy chain amino acid sequence selected from the group consisting of SEQ ID NO: 1, 5, 9, 13, 17, 21, 23, 25, 27, 29, 31, 33, 35, and 37, and a nucleic acid sequence that comprises a nucleic acid sequence encoding a light chain amino acid sequence selected from the group consisting of SEQ ID NO: 3, 7, 11, 15, 19, 39, 41, 43, 45, 47, 49, 51, 53, 55, 57, and 59.
• In some embodiments, the antibody is encoded by a nucleic acid sequence that comprises a nucleic acid sequence encoding a heavy chain amino acid sequence selected from the group consisting of SEQ ID NO: 21, 23, 25, 27, 29, 31, 33, 35, and 37, and a nucleic acid sequence that comprises a nucleic acid sequence encoding a light chain amino acid sequence selected from the group consisting of SEQ ID NO: 39, 41, 43, 45, 47, 49, 51, 53, 55, 57, and 59.
• In some embodiments, the anti-PD-1 is encoded by a nucleic acid sequence that comprises a nucleic acid sequence encoding a heavy chain that comprises or is derived from the amino acid sequence of SEQ ID NO: 1346, and a nucleic acid sequence that comprises a nucleic acid sequence encoding a light chain that comprises or is derived from the amino acid sequence of SEQ ID NO: 626.
• In some embodiments, the anti-PD-1 antibody is encoded by a nucleic acid sequence that comprises a nucleic acid sequence encoding a heavy chain that comprises or is derived from the amino acid sequence of SEQ ID NO: 1514, and a nucleic acid sequence that comprises a nucleic acid sequence encoding a light chain that comprises or is derived from the amino acid sequence of SEQ ID NO: 638.
• In some embodiments, the antibody is encoded by a nucleic acid sequence that comprises a nucleic acid sequence encoding a heavy chain amino acid sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to an amino acid sequence selected from the group consisting of SEQ ID NO: 1, 5, 9, 13, 17, 21, 23, 25, 27, 29, 31, 33, 35, and 37. In some embodiments, the antibody is encoded by a nucleic acid sequence that comprises a nucleic acid sequence encoding a heavy chain amino acid sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to an amino acid sequence selected from the group consisting of SEQ ID NO: 21, 23, 25, 27, 29, 31, 33, 35, and 37.
• In some embodiments, the antibody is encoded by a nucleic acid sequence that comprises a nucleic acid sequence encoding a light chain amino acid that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to the amino acid sequence selected from the group consisting of SEQ ID NO: 3, 7, 11, 15, 19, 39, 41, 43, 45, 47, 49, 51, 53, 55, 57, and 59. In some embodiments, the antibody is encoded by a nucleic acid sequence that comprises a nucleic acid sequence encoding a light chain amino acid that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to the amino acid sequence selected from the group consisting of SEQ ID NO: 39, 41, 43, 45, 47, 49, 51, 53, 55, 57, and 59.
• In some embodiments, the antibody is encoded by a nucleic acid sequence that comprises a nucleic acid sequence encoding a heavy chain amino acid sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to an amino acid sequence selected from the group consisting of SEQ ID NO: 1, 5, 9, 13, 17, 21, 23, 25, 27, 29, 31, 33, 35, and 37, and a nucleic acid sequence encoding a light chain amino acid that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to the amino acid sequence selected from the group consisting of SEQ ID NO: 3, 7, 11, 15, 19, 39, 41, 43, 45, 47, 49, 51, 53, 55, 57, and 59.
• In some embodiments, the antibody is encoded by a nucleic acid sequence that comprises a nucleic acid sequence encoding a heavy chain amino acid sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to an amino acid sequence selected from the group consisting of SEQ ID NO: 21, 23, 25, 27, 29, 31, 33, 35, and 37, and a nucleic acid sequence that comprises a nucleic acid sequence encoding a light chain amino acid that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to the amino acid sequence selected from the group consisting of SEQ ID NO: 39, 41, 43, 45, 47, 49, 51, 53, 55, 57, and 59.
• In some embodiments, the anti-PD-1 is encoded by a nucleic acid sequence that comprises a nucleic acid sequence encoding a heavy chain that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to the amino acid sequence of SEQ ID NO: 1346, and a nucleic acid sequence that comprises a nucleic acid sequence encoding a light chain t that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to the amino acid sequence of SEQ ID NO: 626.
• In some embodiments, the anti-PD-1 antibody is encoded by a nucleic acid sequence that comprises a nucleic acid sequence encoding a heavy chain that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to the amino acid sequence of SEQ ID NO: 1514, and a nucleic acid sequence that comprises a nucleic acid sequence encoding a light chain that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to the amino acid sequence of SEQ ID NO: 638.
• In some embodiments, the antibody is encoded by a heavy chain nucleic acid sequence selected from the group consisting of SEQ ID NO: 2, 6, 10, 14, 18, 22, 24, 26, 28, 30, 32, 34, 36, and 38. In some embodiments, the antibody is encoded by a heavy chain nucleic acid sequence selected from the group consisting of SEQ ID NO: 22, 24, 26, 28, 30, 32, 34, 36, and 38.
• In some embodiments, the antibody is encoded by a light chain nucleic acid sequence selected from the group consisting of SEQ ID NO: 4, 8, 12, 16, 20, 40, 42, 44, 46, 48, 50, 52, 54, 56, 58, and 60. In some embodiments, the antibody is encoded by a light chain nucleic acid sequence selected from the group consisting of SEQ ID NO: 40, 42, 44, 46, 48, 50, 52, 54, 56, 58, and 60.
• In some embodiments, the antibody is encoded by heavy chain nucleic acid sequence selected from the group consisting of SEQ ID NO: selected from the group consisting of SEQ ID NO: 2, 6, 10, 14, 18, 22, 24, 26, 28, 30, 32, 34, 36, and 38, and a light chain nucleic acid sequence selected from the group consisting of SEQ ID NO: 4, 8, 12, 16, 20, 40, 42, 44, 46, 48, 50, 52, 54, 56, 58, and 60. In some embodiments, the antibody is encoded by heavy chain nucleic acid sequence selected from the group consisting of SEQ ID NO: selected from the group consisting of SEQ ID NO: 22, 24, 26, 28, 30, 32, 34, 36, and 38, and a light chain nucleic acid sequence selected from the group consisting of SEQ ID NO: 40, 42, 44, 46, 48, 50, 52, 54, 56, 58, and 60.
• In some embodiments, the antibody is encoded by a nucleic acid sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to a heavy chain nucleic acid sequence selected from the group consisting of SEQ ID NO: 2, 6, 10, 14, 18, 22, 24, 26, 28, 30, 32, 34, 36, and 38. In some embodiments, the antibody is encoded by a nucleic acid sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to a heavy chain nucleic acid sequence selected from the group consisting of SEQ ID NO: 22, 24, 26, 28, 30, 32, 34, 36, and 38.
• In some embodiments, the antibody is encoded by a nucleic acid sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to a light chain nucleic acid sequence selected from the group consisting of SEQ ID NO: 4, 8, 12, 16, 20, 40, 42, 44, 46, 48, 50, 52, 54, 56, 58, and 60. In some embodiments, the antibody is encoded by a nucleic acid sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to a light chain nucleic acid sequence selected from the group consisting of SEQ ID NO: 40, 42, 44, 46, 48, 50, 52, 54, 56, 58, and 60.
• In some embodiments, the antibody is encoded by a nucleic acid sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to a heavy chain nucleic acid sequence selected from the group consisting of SEQ ID NO: 2, 6, 10, 14, 18, 22, 24, 26, 28, 30, 32, 34, 36, and 38, and a nucleic acid sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to a light chain nucleic acid sequence selected from the group consisting of SEQ ID NO: 4, 8, 12, 16, 20, 40, 42, 44, 46, 48, 50, 52, 54, 56, 58, and 60. In some embodiments, the antibody is encoded by a nucleic acid sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to a heavy chain nucleic acid sequence selected from the group consisting of SEQ ID NO: 22, 24, 26, 28, 30, 32, 34, 36, and 38, and a nucleic acid sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to a light chain nucleic acid sequence selected from the group consisting of SEQ ID NO: 40, 42, 44, 46, 48, 50, 52, 54, 56, 58, and 60.
• In some embodiments, the antibody or antigen-binding fragment thereof is incorporated in a multispecific antibody or antigen-binding fragment thereof, where at least one arm of the multispecific antibody specifically binds PD-1. In some embodiments, the antibody or antigen-binding fragment thereof is incorporated in a bispecific antibody or antigen-binding fragment thereof, where at least one arm of the bispecific antibody specifically binds PD-1.
• In some embodiments, at least one arm of the multispecific antibody, e.g., a bispecific antibody, comprises a heavy chain amino acid sequence selected from the group consisting of SEQ ID NO: 1, 5, 9, 13, 17, 21, 23, 25, 27, 29, 31, 33, 35, and 37. In some embodiments, at least one arm of the multispecific antibody, e.g., a bispecific antibody, comprises a heavy chain amino acid sequence selected from the group consisting of SEQ ID NO: 21, 23, 25, 27, 29, 31, 33, 35, and 37.
• In some embodiments, at least one arm of the multispecific antibody, e.g., a bispecific antibody, comprises a light chain amino acid sequence selected from the group consisting of SEQ ID NO: 3, 7, 11, 15, 19, 39, 41, 43, 45, 47, 49, 51, 53, 55, 57, and 59. In some embodiments, at least one arm of the multispecific antibody, e.g., a bispecific antibody, comprises a light chain amino acid sequence selected from the group consisting of SEQ ID NO: 39, 41, 43, 45, 47, 49, 51, 53, 55, 57, and 59.
• In some embodiments, at least one arm of the multispecific antibody, e.g., a bispecific antibody, includes a heavy chain amino acid sequence comprising an amino acid sequence selected from the group consisting of SEQ ID NO: 1, 5, 9, 13, 17, 21, 23, 25, 27, 29, 31, 33, 35, and 37, and a light chain amino acid sequence selected from the group consisting of SEQ ID NO: 3, 7, 11, 15, 19, 39, 41, 43, 45, 47, 49, 51, 53, 55, 57, and 59. In some embodiments, at least one arm of the multispecific antibody, e.g., a bispecific antibody, includes a heavy chain amino acid sequence comprising an amino acid sequence selected from the group consisting of SEQ ID NO: 21, 23, 25, 27, 29, 31, 33, 35, and 37, and a light chain amino acid sequence selected from the group consisting of SEQ ID NO: 39, 41, 43, 45, 47, 49, 51, 53, 55, 57, and 59.
• In some embodiments, at least one arm of the multispecific antibody, e.g., a bispecific antibody, includes a heavy chain that comprises or is derived from amino acid sequence SEQ ID NO: 21. In some embodiments, at least one arm of the multispecific antibody, e.g., a bispecific antibody, includes a light chain that comprises or is derived from amino acid sequence SEQ ID NO: 45 or SEQ ID NO: 47. In some embodiments, at least one arm of the multispecific antibody, e.g., a bispecific antibody, includes a heavy chain that comprises or is derived from amino acid sequence SEQ ID NO: 21 and a light chain that comprises or is derived from amino acid sequence SEQ ID NO: 45 or SEQ ID NO: 47. In some embodiments, at least one arm of the multispecific antibody, e.g., a bispecific antibody, includes a heavy chain that comprises or is derived from amino acid sequence SEQ ID NO: 21 and a light chain that comprises or is derived from amino acid sequence SEQ ID NO: 45. In some embodiments, at least one arm of the multispecific antibody, e.g., a bispecific antibody, includes a heavy chain that comprises or is derived from amino acid sequence SEQ ID NO: 21 and a light chain that comprises or is derived from amino acid sequence SEQ ID NO: 47.
• In some embodiments, at least one arm of the multispecific antibody, e.g., a bispecific antibody, includes the combination of the complementarity determining region (CDR) sequences of the heavy chain amino acid sequence of SEQ ID NO: 21. In some embodiments, at least one arm of the multispecific antibody, e.g., a bispecific antibody, includes the combination of the CDR sequences of the light chain amino acid sequence of SEQ ID NO: 45 or of SEQ ID NO: 47. In some embodiments, at least one arm of the multispecific antibody, e.g., a bispecific antibody, includes a combination of the CDR sequences of the heavy chain amino acid sequence of SEQ ID NO: 21, and the CDR sequences of the light chain amino acid sequence of SEQ ID NO: 45 or 47. In some embodiments, at least one arm of the multispecific antibody, e.g., a bispecific antibody, includes a combination of the CDR sequences of the heavy chain amino acid sequence of SEQ ID NO: 21, and the CDR sequences of the light chain amino acid sequence of SEQ ID NO: 45. In some embodiments, at least one arm of the multispecific antibody, e.g., a bispecific antibody, includes a combination of the CDR sequences of the heavy chain amino acid sequence of SEQ ID NO: 21, and the CDR sequences of the light chain amino acid sequence of SEQ ID NO: 47.
• In some embodiments, at least one arm of the multispecific antibody, e.g., a bispecific antibody includes: (a) a variable heavy chain complementarity determining region 1 (VH CDR1) comprising an amino acid sequence selected from the group consisting of SEQ ID NOs: 653-657; (b) a variable heavy chain complementarity determining region 2 (VH CDR2) comprising an amino acid sequence selected from the group consisting of SEQ ID NOs: 658-663; (c) a variable heavy chain complementarity determining region 3 (VH CDR3) comprising an amino acid sequence selected from the group consisting of SEQ ID NOs: 664-668; (d) a variable light chain complementarity determining region 1 (VL CDR1) comprising an amino acid sequence selected from the group consisting of SEQ ID NOs: 669-677; (e) a variable light chain complementarity determining region 2 (VL CDR2) comprising an amino acid sequence selected from the group consisting of SEQ ID NOs: 678-682; and (f) variable light chain complementarity determining region 3 (VL CDR3) comprising an amino acid sequence selected from the group consisting of SEQ ID NOs: 683-687
• In some embodiments, at least one arm of the multispecific antibody, e.g., a bispecific antibody, includes a combination of a variable heavy chain complementarity determining region 1 (VH CDR1, also referred to herein as CDRH1) sequence, a variable heavy chain complementarity determining region 2 (VH CDR2, also referred to herein as CDRH2) sequence, and a variable heavy chain complementarity determining region 3 (VH CDR3, also referred to herein as CDRH3) sequence, wherein the VH CDR1 sequence comprises GFTFSGYAMS (SEQ ID NO: 653); the VH CDR2 sequence comprises YISNSGGNAH (SEQ ID NO: 658); and the VH CDR3 sequence comprises EDYGTSPFVY (SEQ ID NO: 664).
• In some embodiments, at least one arm of the multispecific antibody, e.g., a bispecific antibody, includes a combination of a variable light chain complementarity determining region 1 (VL CDR1, also referred to herein as CDRL1) sequence, a variable light chain complementarity determining region 2 (VL CDR2, also referred to herein as CDRL2) sequence, and a variable light chain complementarity determining region 3 (VL CDR3, also referred to herein as CDRL3) sequence, wherein the VL CDR1 sequence comprises RASESVDSYGISFMN (SEQ ID NO: 675) or RASESVDAYGISFMN (SEQ ID NO:676); the VL CDR2 sequence comprises AASNQGS (SEQ ID NO: 678); and the VL CDR3 sequence comprises QQSKDVPWT (SEQ ID NO: 683). In some embodiments, at least one arm of the multispecific antibody, e.g., a bispecific antibody, includes a combination of a VL CDR1 sequence, a VL CDR2 sequence, and a VL CDR3 sequence, wherein the VL CDR1 sequence comprises RASESVDSYGISFMN (SEQ ID NO: 675); the VL CDR2 sequence comprises AASNQGS (SEQ ID NO: 678); and the VL CDR3 sequence comprises QQSKDVPWT (SEQ ID NO: 683). In some embodiments, at least one arm of the multispecific antibody, e.g., a bispecific antibody, includes a combination of a VL CDR1 sequence, a VL CDR2 sequence, and a VL CDR3 sequence, wherein the VL CDR1 sequence comprises RASESVDAYGISFMN (SEQ ID NO:676); the VL CDR2 sequence comprises AASNQGS (SEQ ID NO: 678); and the VL CDR3 sequence comprises QQSKDVPWT (SEQ ID NO: 683).
• In some embodiments, at least one arm of the multispecific antibody, e.g., a bispecific antibody, includes a combination of a VH CDR1 sequence, a VH CDR2 sequence, a VH CDR3 sequence, a VL CDR1 sequence, a VL CDR2 sequence, and a VL CDR3 sequence, wherein the VH CDR1 sequence comprises GFTFSGYAMS (SEQ ID NO: 653); the VH CDR2 sequence comprises YISNSGGNAH (SEQ ID NO: 658); and the VH CDR3 sequence comprises EDYGTSPFVY (SEQ ID NO: 664); the VL CDR1 sequence comprises RASESVDSYGISFMN (SEQ ID NO: 675) or RASESVDAYGISFMN (SEQ ID NO:676); the VL CDR2 sequence comprises AASNQGS (SEQ ID NO: 678); and the VL CDR3 sequence comprises QQSKDVPWT (SEQ ID NO: 683). In some embodiments, at least one arm of the multispecific antibody, e.g., a bispecific antibody, includes a combination of a VH CDR1 sequence, a VH CDR2 sequence, a VH CDR3 sequence, a VL CDR1 sequence, a VL CDR2 sequence, and a VL CDR3 sequence, wherein the VH CDR1 sequence comprises GFTFSGYAMS (SEQ ID NO: 653); the VH CDR2 sequence comprises YISNSGGNAH (SEQ ID NO: 658); and the VH CDR3 sequence comprises EDYGTSPFVY (SEQ ID NO: 664); the VL CDR1 sequence comprises RASESVDSYGISFMN (SEQ ID NO: 675); the VL CDR2 sequence comprises AASNQGS (SEQ ID NO: 678); and the VL CDR3 sequence comprises QQSKDVPWT (SEQ ID NO: 683). In some embodiments, at least one arm of the multispecific antibody, e.g., a bispecific antibody, includes a combination of a VH CDR1 sequence, a VH CDR2 sequence, a VH CDR3 sequence, a VL CDR1 sequence, a VL CDR2 sequence, and a VL CDR3 sequence, wherein the VH CDR1 sequence comprises GFTFSGYAMS (SEQ ID NO: 653); the VH CDR2 sequence comprises YISNSGGNAH (SEQ ID NO: 658); and the VH CDR3 sequence comprises EDYGTSPFVY (SEQ ID NO: 664); the VL CDR1 sequence comprises RASESVDAYGISFMN (SEQ ID NO:676); the VL CDR2 sequence comprises AASNQGS (SEQ ID NO: 678); and the VL CDR3 sequence comprises QQSKDVPWT (SEQ ID NO: 683).
• In some embodiments, at least one arm of the multispecific antibody, e.g., a bispecific antibody, includes a heavy chain that comprises or is derived from the amino acid sequence of SEQ ID NO: 1346, and a light chain that comprises or is derived from the amino acid sequence of SEQ ID NO: 626.
• In some embodiments, at least one arm of the multispecific antibody, e.g., a bispecific antibody, includes a heavy chain that comprises or is derived from the amino acid sequence of SEQ ID NO: 1514, and a light chain that comprises or is derived from the amino acid sequence of SEQ ID NO: 638.
• In some embodiments, at least one arm of the multispecific antibody, e.g., a bispecific antibody, includes the combination of the complementarity determining region (CDR) sequences of the heavy chain amino acid sequence of SEQ ID NO: 1346. In some embodiments, at least one arm of the multispecific antibody, e.g., a bispecific antibody, includes the combination of the CDR sequences of the light chain amino acid sequence of SEQ ID NO: 626. In some embodiments, at least one arm of the multispecific antibody, e.g., a bispecific antibody, includes a combination of the CDR sequences of the heavy chain amino acid sequence of SEQ ID NO: 1346, and the CDR sequences of the light chain amino acid sequence of SEQ ID NO: 626.
• In some embodiments, at least one arm of the multispecific antibody, e.g., a bispecific antibody, includes a combination of a variable heavy chain complementarity determining region 1 (VH CDR1, also referred to herein as CDRH1) sequence, a variable heavy chain complementarity determining region 2 (VH CDR2, also referred to herein as CDRH2) sequence, and a variable heavy chain complementarity determining region 3 (VH CDR3, also referred to herein as CDRH3) sequence, wherein the VH CDR1 sequence comprises GITFSNSG (SEQ ID NO: 1705); the VH CDR2 sequence comprises IWYDGSKR (SEQ ID NO: 1706); and the VH CDR3 sequence comprises TNDDY (SEQ ID NO: 1707).
• In some embodiments, at least one arm of the multispecific antibody, e.g., a bispecific antibody, includes a combination of a variable light chain complementarity determining region 1 (VL CDR1, also referred to herein as CDRL1) sequence, a variable light chain complementarity determining region 2 (VL CDR2, also referred to herein as CDRL2) sequence, and a variable light chain complementarity determining region 3 (VL CDR3, also referred to herein as CDRL3) sequence, wherein the VL CDR1 sequence comprises QSVSSY (SEQ ID NO: 1708); the VL CDR2 sequence comprises DAS (SEQ ID NO: 1709); and the VL CDR3 sequence comprises QQSSNWPRT (SEQ ID NO: 1710).
• In some embodiments, at least one arm of the multispecific antibody, e.g., a bispecific antibody, includes a combination of a VH CDR1 sequence, a VH CDR2 sequence, a VH CDR3 sequence, a VL CDR1 sequence, a VL CDR2 sequence, and a VL CDR3 sequence, wherein the VH CDR1 sequence comprises GITFSNSG (SEQ ID NO: 1705); the VH CDR2 sequence comprises IWYDGSKR (SEQ ID NO: 1706); the VH CDR3 sequence comprises TNDDY (SEQ ID NO: 1707); the VL CDR1 sequence comprises QSVSSY (SEQ ID NO: 1708); the VL CDR2 sequence comprises DAS (SEQ ID NO: 1709); and the VL CDR3 sequence comprises QQSSNWPRT (SEQ ID NO: 1710).
• In some embodiments, at least one arm of the multispecific antibody, e.g., a bispecific antibody, includes the combination of the complementarity determining region (CDR) sequences of the heavy chain amino acid sequence of SEQ ID NO: 1514. In some embodiments, at least one arm of the multispecific antibody, e.g., a bispecific antibody, includes the combination of the CDR sequences of the light chain amino acid sequence of SEQ ID NO: 638. In some embodiments, at least one arm of the multispecific antibody, e.g., a bispecific antibody, includes a combination of the CDR sequences of the heavy chain amino acid sequence of SEQ ID NO: 1514, and the CDR sequences of the light chain amino acid sequence of SEQ ID NO: 638.
• In some embodiments, at least one arm of the multispecific antibody, e.g., a bispecific antibody, includes a combination of a variable heavy chain complementarity determining region 1 (VH CDR1, also referred to herein as CDRH1) sequence, a variable heavy chain complementarity determining region 2 (VH CDR2, also referred to herein as CDRH2) sequence, and a variable heavy chain complementarity determining region 3 (VH CDR3, also referred to herein as CDRH3) sequence, wherein the VH CDR1 sequence comprises GYTFTNYY (SEQ ID NO: 1711); the VH CDR2 sequence comprises INPSNGGT (SEQ ID NO: 1712); and the VH CDR3 sequence comprises RRDYRFDMGFDY (SEQ ID NO: 1713).
• In some embodiments, at least one arm of the multispecific antibody, e.g., a bispecific antibody, includes a combination of a variable light chain complementarity determining region 1 (VL CDR1, also referred to herein as CDRL1) sequence, a variable light chain complementarity determining region 2 (VL CDR2, also referred to herein as CDRL2) sequence, and a variable light chain complementarity determining region 3 (VL CDR3, also referred to herein as CDRL3) sequence, wherein the VL CDR1 sequence comprises KGVSTSGYSY (SEQ ID NO: 1714); the VL CDR2 sequence comprises LAS (SEQ ID NO: 1715); and the VL CDR3 sequence comprises QHSRDLPLT (SEQ ID NO: 1716).
• In some embodiments, at least one arm of the multispecific antibody, e.g., a bispecific antibody, includes a combination of a VH CDR1 sequence, a VH CDR2 sequence, a VH CDR3 sequence, a VL CDR1 sequence, a VL CDR2 sequence, and a VL CDR3 sequence, wherein the VH CDR1 sequence comprises GYTFTNYY (SEQ ID NO: 1711); the VH CDR2 sequence comprises INPSNGGT (SEQ ID NO: 1712); the VH CDR3 sequence comprises RRDYRFDMGFDY (SEQ ID NO: 1713); the VL CDR1 sequence comprises KGVSTSGYSY (SEQ ID NO: 1714); the VL CDR2 sequence comprises LAS (SEQ ID NO: 1715); and the VL CDR3 sequence comprises QHSRDLPLT (SEQ ID NO: 1716).
• In some embodiments, at least one arm of the multispecific antibody, e.g., a bispecific antibody, comprises a heavy chain amino acid sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to an amino acid sequence selected from the group consisting of SEQ ID NO: 1, 5, 9, 13, 17, 21, 23, 25, 27, 29, 31, 33, 35, and 37. In some embodiments, at least one arm of the multispecific antibody, e.g., a bispecific antibody, comprises a heavy chain amino acid sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to an amino acid sequence selected from the group consisting of SEQ ID NO: 21, 23, 25, 27, 29, 31, 33, 35, and 37.
• In some embodiments, at least one arm of the multispecific antibody, e.g., a bispecific antibody, comprises a light chain amino acid that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to an amino acid sequence selected from the group consisting of SEQ ID NO: 3, 7, 11, 15, 19, 39, 41, 43, 45, 47, 49, 51, 53, 55, 57, and 59. In some embodiments, at least one arm of the multispecific antibody, e.g., a bispecific antibody, comprises a light chain amino acid that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to an amino acid sequence selected from the group consisting of SEQ ID NO: 39, 41, 43, 45, 47, 49, 51, 53, 55, 57, and 59.
• In some embodiments, at least one arm of the multispecific antibody, e.g., a bispecific antibody, comprises a heavy chain amino acid sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to an amino acid sequence selected from the group consisting of SEQ ID NO: 1, 5, 9, 13, 17, 21, 23, 25, 27, 29, 31, 33, 35, and 37, and a light chain amino acid that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to an amino acid sequence selected from the group consisting of SEQ ID NO: 3, 7, 11, 15, 19, 39, 41, 43, 45, 47, 49, 51, 53, 55, 57, and 59.
• In some embodiments, at least one arm of the multispecific antibody, e.g., a bispecific antibody, includes a heavy chain amino acid sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to the amino acid sequence of SEQ ID NO: 1346, and a light chain amino acid that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to the amino acid sequence of SEQ ID NO: 626.
• In some embodiments, at least one arm of the multispecific antibody, e.g., a bispecific antibody, includes a heavy chain amino acid sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to the amino acid sequence of SEQ ID NO: 1514, and a light chain amino acid that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to the amino acid sequence of SEQ ID NO: 638.
• In some embodiments, at least one arm of the multispecific antibody, e.g., a bispecific antibody, includes a combination of a VH CDR1 sequence, a VH CDR2 sequence, and a VH CDR3 sequence, wherein the VH CDR1 sequence comprises a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to GITFSNSG (SEQ ID NO: 1705); the VH CDR2 sequence comprises a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to IWYDGSKR (SEQ ID NO: 1706); and the VH CDR3 sequence comprises a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to TNDDY (SEQ ID NO: 1707).
• In some embodiments, at least one arm of the multispecific antibody, e.g., a bispecific antibody, includes a combination of a VL CDR1 sequence, a VL CDR2 sequence, and a VL CDR3 sequence, wherein the VL CDR1 sequence comprises a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to QSVSSY (SEQ ID NO: 1708); the VL CDR2 sequence comprises a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to DAS (SEQ ID NO: 1709); and the VL CDR3 sequence comprises a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to QQSSNWPRT (SEQ ID NO: 1710).
• In some embodiments, at least one arm of the multispecific antibody, e.g., a bispecific antibody, includes a combination of a VH CDR1 sequence, a VH CDR2 sequence, a VH CDR3 sequence, a VL CDR1 sequence, a VL CDR2 sequence, and a VL CDR3 sequence, wherein the VH CDR1 sequence comprises a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to GITFSNSG (SEQ ID NO: 1705); the VH CDR2 sequence comprises a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to IWYDGSKR (SEQ ID NO: 1706); the VH CDR3 sequence comprises a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to TNDDY (SEQ ID NO: 1707); the VL CDR1 sequence comprises a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to QSVSSY (SEQ ID NO: 1708); the VL CDR2 sequence comprises a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to DAS (SEQ ID NO: 1709); and the VL CDR3 sequence comprises a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to QQSSNWPRT (SEQ ID NO: 1710).
• In some embodiments, at least one arm of the multispecific antibody, e.g., a bispecific antibody, includes a combination of a VH CDR1 sequence, a VH CDR2 sequence, and a VH CDR3 sequence, wherein the VH CDR1 sequence comprises a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to GYTFTNYY (SEQ ID NO: 1711); the VH CDR2 sequence comprises a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to INPSNGGT (SEQ ID NO: 1712); and the VH CDR3 sequence comprises a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to RRDYRFDMGFDY (SEQ ID NO: 1713).
• In some embodiments, at least one arm of the multispecific antibody, e.g., a bispecific antibody, includes a combination of a VL CDR1 sequence, a VL CDR2 sequence, and a VL CDR3 sequence, wherein the VL CDR1 sequence comprises a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to KGVSTSGYSY (SEQ ID NO: 1714); the VL CDR2 sequence comprises a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to LAS (SEQ ID NO: 1715); and the VL CDR3 sequence comprises a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to QHSRDLPLT (SEQ ID NO: 1716).
• In some embodiments, at least one arm of the multispecific antibody, e.g., a bispecific antibody, includes a combination of a VH CDR1 sequence, a VH CDR2 sequence, a VH CDR3 sequence, a VL CDR1 sequence, a VL CDR2 sequence, and a VL CDR3 sequence, wherein the VH CDR1 sequence comprises a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to GYTFTNYY (SEQ ID NO: 1711); the VH CDR2 sequence comprises a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to INPSNGGT (SEQ ID NO: 1712); the VH CDR3 sequence comprises a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to RRDYRFDMGFDY (SEQ ID NO: 1713); the VL CDR1 sequence comprises a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to KGVSTSGYSY (SEQ ID NO: 1714); the VL CDR2 sequence comprises a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to LAS (SEQ ID NO: 1715); and the VL CDR3 sequence comprises a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to QHSRDLPLT (SEQ ID NO: 1716).
• In some embodiments, at least one arm of the multispecific antibody, e.g., a bispecific antibody, comprises a combination of a variable heavy chain complementarity determining region 1 (VH CDR1, also referred to herein as CDRH1) sequence, a variable heavy chain complementarity determining region 2 (VH CDR2, also referred to herein as CDRH2) sequence, a variable heavy chain complementarity determining region 3 (VH CDR3, also referred to herein as CDRH3) sequence, a variable light chain complementarity determining region 1 (VL CDR1, also referred to herein as CDRL1) sequence, a variable light chain complementarity determining region 2 (VL CDR2, also referred to herein as CDRL2) sequence, and a variable light chain complementarity determining region 3 (VL CDR3, also referred to herein as CDRL3) sequence, wherein at least one CDR sequence is selected from the group consisting of a VH CDR1 sequence shown in Table 8; a VH CDR2 sequence shown in Table 8; a VH CDR3 sequence shown in Table 8; a VL CDR1 sequence shown in Table 8; a VL CDR2 sequence shown in Table 8; and a VL CDR3 sequence shown in Table 8.
• In some embodiments, at least one arm of the multispecific antibody, e.g., a bispecific antibody, comprises a combination of a VH CDR1 sequence, a VH CDR2 sequence, a VH CDR3 sequence, a VL CDR1 sequence, a VL CDR2 sequence, and a VL CDR3 sequence, wherein at least one CDR sequence is selected from the group consisting of a VH CDR1 sequence that includes a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to a VH CDR1 sequence shown in Table 8; a VH CD2 sequence that includes a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to a VH CDR2 sequence shown in Table 8; a VH CDR3 sequence that includes a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to a VH CDR3 sequence shown in Table 8; a VL CDR1 sequence that includes a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to a VL CDR1 sequence shown in Table 8; a VL CDR2 sequence that includes a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to a VL CDR2 sequence shown in Table 8; and a VL CDR3 sequence that includes a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to a VL CDR3 sequence shown in Table 8.
• In some embodiments, at least one arm of the multispecific antibody, e.g., a bispecific antibody, comprises a combination of a VH CDR1 sequence, a VH CDR2 sequence, a VH CDR3 sequence, a VL CDR1 sequence, a VL CDR2 sequence, and a VL CDR3 sequence, wherein the combination is a combination of the six CDR sequences (VH CDR1, VH CDR2, VH CDR3, VL CDR1, VL CDR2, and VL CDR3) shown in a single row in Table 8.
• In some embodiments, at least one arm of the multispecific antibody, e.g., a bispecific antibody, comprises a heavy chain that comprises a combination of a VH CDR1 sequence, a VH CDR2 sequence, and a VH CDR3 sequence, wherein the combination is a combination of the three heavy chain CDR sequences (VH CDR1, VH CDR2, VH CDR3) shown in a single row in Table 8.
• In some embodiments, at least one arm of the multispecific antibody, e.g., a bispecific antibody, comprises a combination of a VH CDR1 sequence, a VH CDR2 sequence, a VH CDR3 sequence shown in a single row in Table 8, a VL CDR1 sequence, a VL CDR2 sequence, and a VL CDR3 sequence shown in a single row in Table 8, wherein each CDR sequence in the combination comprises a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to the corresponding VH CDR sequence shown in a single row in Table 8 and the corresponding VL CDR shown in a single row in Table 8.
• In some embodiments, at least one arm of the multispecific antibody, e.g., a bispecific antibody, comprises a heavy chain that comprises a combination of a VH CDR1 sequence, a VH CDR2 sequence, and a VH CDR3 sequence, wherein each CDR sequence in the combination comprises a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to the corresponding CDR sequence in a combination of three heavy chain CDR sequences (VH CDR1, VH CDR2, VH CDR3) shown in a single row in Table 8.
• The disclosure also provides activatable antibodies that include an antibody or antigen-binding fragment thereof that specifically binds PD-1 coupled to a masking moiety (MM), such that coupling of the MM reduces the ability of the antibody or antigen-binding fragment thereof to bind PD-1. In some embodiments, the MM is coupled via a cleavable moiety (CM) that includes sequence that functions as a substrate for a protease. The activatable anti-PD-1 antibodies of the disclosure are activated when the cleavable moiety is cleaved by a protease. For example, the protease is produced by a tumor that is in proximity to T cells that express PD-1. In some embodiments, the protease is produced by a tumor that is co-localized with T cells that express PD-1.
• The activatable anti-PD-1 antibodies provided herein, also referred to herein as anti-PD-1 activatable antibodies or PD-1 activatable antibodies, are stable in circulation, activated at intended sites of therapy and/or diagnosis but not in normal, e.g., healthy tissue or other tissue not targeted for treatment and/or diagnosis, and, when activated, exhibit binding to PD-1 that is at least comparable to the corresponding, unmodified antibody.
• The invention also provides methods of treating, preventing and/or delaying the onset or progression of, or alleviating a symptom associated with aberrant expression and/or activity of PD-1 in a subject using antibodies or activatable antibodies that bind PD-1, particularly activatable antibodies that bind and neutralize or otherwise inhibit at least one biological activity of PD-1.
• In some embodiments, the activatable anti-PD-1 antibody comprises an activatable antibody that, in an activated state, specifically binds to mammalian PD-1, wherein said activatable antibody comprises: an antibody or an antigen binding fragment thereof (AB) that specifically binds to mammalian PD-1; a masking moiety (MM) that inhibits the binding of the AB to mammalian PD-1 when the activatable antibody is in an uncleaved state; and a cleavable moiety (CM) coupled to the AB, wherein the CM is a polypeptide that functions as a substrate for a protease.
• In some embodiments, the activatable anti-PD-1 antibody comprises an activatable antibody that, in an activated state, (a) specifically binds to mammalian PD-1; and (b) specifically blocks a natural ligand of PD-1 from binding to the mammalian PD-1, wherein the activatable antibody comprises: an antibody or an antigen binding fragment thereof (AB) that specifically binds to mammalian PD-1; a masking moiety (MM) that inhibits the binding of the AB to mammalian PD-1 when the activatable antibody is in an uncleaved state; and a cleavable moiety (CM) coupled to the AB, wherein the CM is a polypeptide that functions as a substrate for a protease.
• In some embodiments, the activatable antibody in an uncleaved state specifically binds to the mammalian PD-1 with a dissociation constant of 0.5 nM to 1 nM, 0.5 nM to 2 nM, 0.5 nM to 5 nM, 0.5 nM to 10 nM, 0.5 nM to 15 nM, 0.5 nM to 20 nM, 0.5 nM to 25 nM, 0.5 nM to 50 nM, 0.5 nM to 75 nM, 0.5 nM to 100 nM, 0.5 nM to 150 nM, 0.5 nM to 200 nM, 0.5 nM to 300 nM, 0.5 nM to 400 nM, 1 nM to 2 nM, 1 nM to 5 nM, 1 nM to 10 nM, 1 nM to 15 nM, 1 nM to 20 nM, 1 nM to 25 nM, 1 nM to 50 nM, 1 nM to 75 nM, 1 nM to 100 nM, 1 nM to 150 nM, 1 nM to 200 nM, 1 nM to 300 nM, 1 nM to 400 nM, 2 nM to 5 nM, 2 nM to 10 nM, 2 nM to 15 nM, 2 nM to 20 nM, 2 nM to 25 nM, 2 nM to 50 nM, 2 nM to 75 nM, 2 nM to 100 nM, 2 nM to 150 nM, 2 nM to 200 nM, 2 nM to 300 nM, 2 nM to 400 nM, 5 nM to 10 nM, 5 nM to 15 nM, 5 nM to 20 nM, 5 nM to 25 nM, 5 nM to 50 nM, 5 nM to 75 nM, 5 nM to 100 nM, 5 nM to 150 nM, 5 nM to 200 nM, 5 nM to 300 nM, 5 nM to 400 nM, 10 nM to 15 nM, 10 nM to 20 nM, 10 nM to 25 nM, 10 nM to 50 nM, 10 nM to 75 nM, 10 nM to 100 nM, 10 nM to 150 nM, 10 nM to 200 nM, 10 nM to 300 nM, 10 nM to 400 nM, 15 nM to 20 nM, 15 nM to 25 nM, 15 nM to 50 nM, 15 nM to 75 nM, 15 nM to 100 nM, 15 nM to 150 nM, 15 nM to 200 nM, 15 nM to 300 nM, 15 nM to 400 nM, 20 nM to 25 nM, 20 nM to 50 nM, 20 nM to 75 nM, 20 nM to 100 nM, 20 nM to 150 nM, 20 nM to 200 nM, 20 nM to 300 nM, 20 nM to 400 nM, 25 nM to 50 nM, 25 nM to 75 nM, 25 nM to 100 nM, 25 nM to 150 nM, 25 nM to 200 nM, 25 nM to 300 nM, 25 nM to 400 nM, 50 nM to 75 nM, 50 nM to 100 nM, 50 nM to 150 nM, 50 nM to 200 nM, 50 nM to 300 nM, 50 nM to 400 nM, 75 nM to 100 nM, 75 nM to 150 nM, 75 nM to 200 nM, 75 nM to 300 nM, 75 nM to 400 nM, 100 nM to 150 nM, 100 nM to 200 nM, 100 nM to 300 nM, 100 nM to 400 nM, 150 nM to 200 nM, 150 nM to 300 nM, 150 nM to 400 nM, 200 nM to 300 nM, 200 nM to 400 nM, or 300 nM to 400 nM.
• In some embodiments, the activatable antibody in an activated state specifically binds to the mammalian PD-1 with a dissociation constant of 0.01 nM to 5 nM, 0.05 nM to 5 nM, 0.1 nM to 5 nM, 0.2 nM to 5 nM, 0.3 nM to 5 nM, 0.4 nM to 5 nM, 0.5 nM to 5 nM, 0.75 nM to 5 nM, 1 nM to 5 nM, 2 nM to 5 nM, 0.01 nM to 2 nM, 0.05 nM to 2 nM, 0.1 nM to 2 nM, 0.2 nM to 2 nM, 0.3 nM to 2 nM, 0.4 nM to 2 nM, 0.5 nM to 2 nM, 0.75 nM to 1 nM, 1 nM to 2 nM, 0.01 nM to 1 nM, 0.05 nM to 1 nM, 0.1 nM to 1 nM, 0.2 nM to 1 nM, 0.3 nM to 1 nM, 0.4 nM to 1 nM, 0.5 nM to 1 nM, 0.75 nM to 1 nM, 0.01 nM to 0.75 nM, 0.05 nM to 0.75 nM, 0.1 nM to 0.75 nM, 0.2 nM to 0.75 nM, 0.3 nM to 0.75 nM, 0.4 nM to 0.75 nM, 0.5 nM to 0.75 nM, 0.01 nM to 0.5 nM, 0.05 nM to 0.5 nM, 0.1 nM to 0.5 nM, 0.2 nM to 0.5 nM, 0.3 nM to 0.5 nM, 0.4 nM to 0.5 nM, 0.01 nM to 0.4 nM, 0.05 nM to 0.4 nM, 0.1 nM to 0.4 nM, 0.2 nM to 0.4 nM, 0.3 nM to 0.4 nM, 0.01 nM to 0.3 nM, 0.05 nM to 0.3 nM, 0.1 nM to 0.3 nM, 0.2 nM to 0.3 nM, 0.01 nM to 0.2 nM, 0.05 nM to 0.2 nM, 0.1 nM to 0.2 nM, 0.01 nM to 0.1 nM, 0.05 nM to 0.1 nM, or 0.01 nM to 0.05 nM.
• In some embodiments, the activatable antibody comprises an AB that specifically binds to the mammalian PD-1 with a dissociation constant of 0.01 nM to 5 nM, 0.05 nM to 5 nM, 0.1 nM to 5 nM, 0.2 nM to 5 nM, 0.3 nM to 5 nM, 0.4 nM to 5 nM, 0.5 nM to 5 nM, 0.75 nM to 5 nM, 1 nM to 5 nM, 2 nM to 5 nM, 0.01 nM to 2 nM, 0.05 nM to 2 nM, 0.1 nM to 2 nM, 0.2 nM to 2 nM, 0.3 nM to 2 nM, 0.4 nM to 2 nM, 0.5 nM to 2 nM, 0.75 nM to 1 nM, 1 nM to 2 nM, 0.01 nM to 1 nM, 0.05 nM to 1 nM, 0.1 nM to 1 nM, 0.2 nM to 1 nM, 0.3 nM to 1 nM, 0.4 nM to 1 nM, 0.5 nM to 1 nM, 0.75 nM to 1 nM, 0.01 nM to 0.75 nM, 0.05 nM to 0.75 nM, 0.1 nM to 0.75 nM, 0.2 nM to 0.75 nM, 0.3 nM to 0.75 nM, 0.4 nM to 0.75 nM, 0.5 nM to 0.75 nM, 0.01 nM to 0.5 nM, 0.05 nM to 0.5 nM, 0.1 nM to 0.5 nM, 0.2 nM to 0.5 nM, 0.3 nM to 0.5 nM, 0.4 nM to 0.5 nM, 0.01 nM to 0.4 nM, 0.05 nM to 0.4 nM, 0.1 nM to 0.4 nM, 0.2 nM to 0.4 nM, 0.3 nM to 0.4 nM, 0.01 nM to 0.3 nM, 0.05 nM to 0.3 nM, 0.1 nM to 0.3 nM, 0.2 nM to 0.3 nM, 0.01 nM to 0.2 nM, 0.05 nM to 0.2 nM, 0.1 nM to 0.2 nM, 0.01 nM to 0.1 nM, 0.05 nM to 0.1 nM, or 0.01 nM to 0.05 nM.
• In some embodiments, the mammalian PD-1 is selected from the group consisting of a human PD-1 and a cynomolgus monkey PD-1. In some embodiments, the AB specifically binds to human PD-1 or cynomolgus monkey PD-1 with a dissociation constant of less than or equal to 1 nM. In some embodiments, the mammalian PD-1 is a human PD-1. In some embodiments, the AB has one or more of the characteristics selected from the group consisting of: (a) the AB specifically binds human PD-1 and cynomolgus monkey PD-1; (b) the AB inhibits binding of human PDL1 and human PDL2 to human PD-1; and (c) the AB inhibits binding of cynomolgus monkey PDL1 and cynomolgus monkey PDL2 to cynomolgus monkey PD-1.
• In some embodiments, the mammalian PD-1 is mouse PD-1. In some embodiments, the activatable antibody comprises an AB that specifically binds mouse PD-1 or inhibits binding of mouse PDL1 and mouse PDL2 to mouse PD1.
• In some embodiments, the activatable antibody in an uncleaved state specifically binds to the mammalian PD-1 with a dissociation constant greater than or equal to 0.5 nM, greater than or equal to 1 nM, greater than or equal to 2 nM, greater than or equal to 3 nM, greater than or equal to 4 nM, greater than or equal to 5 nM, greater than or equal to 10 nM, greater than or equal to 15 nM, greater than or equal to 20 nM, greater than or equal to 25 nM, greater than or equal to 50 nM, greater than or equal to 75 nM, greater than or equal to 100 nM, greater than or equal to 150 nM, greater than or equal to 200 nM, greater than or equal to 300 nM and/or greater than or equal to 400 nM.
• In some embodiments, the activatable antibody in an activated state specifically binds to the mammalian PD-1 with a dissociation constant less than or equal to 0.01 nM, less than or equal to 0.05 nM, less than or equal to 0.1 nM, less than or equal to 0.2 nM, less than or equal to 0.3 nM, less than or equal to 0.4 nM, less than or equal to 0.5 nM, less than or equal to 0.75 nM, and less than or equal to 1 nM.
• In some embodiments, the activatable antibody comprises an AB that specifically binds to the mammalian PD-1 with a dissociation constant less than or equal to 0.01 nM, less than or equal to 0.05 nM, less than or equal to 0.1 nM, less than or equal to 0.2 nM, less than or equal to 0.3 nM, less than or equal to 0.4 nM, less than or equal to 0.5 nM, less than or equal to 0.75 nM, and less than or equal to 1 nM.
• In some embodiments, the activatable antibody comprises an AB blocks the ability of a natural ligand to bind to the mammalian PDL1 with an EC₅₀ of 0.1 nM to 10 nM, 0.1 nM to 5 nM, 0.1 nM to 3 nM, 0.1 nM to 2 nM, 0.1 nM to 1 nM, 0.1 nM to 0.5 nM, 0.1 nM to 0.25 nM, 0.25 nM to 10 nM, 0.25 nM to 5 nM, 0.25 nM to 3 nM, 0.25 nM to 2 nM, 0.25 nM to 1 nM, 0.25 nM to 0.5 nM, 0.5 nM to 10 nM, 0.5 nM to 5 nM, 0.5 nM to 3 nM, 0.5 nM to 2 nM, 0.5 nM to 1 nM, 1 nM to 10 nM, 1 nM to 5 nM, 1 nM to 3 nM, 1 nM to 2 nM, 2 nM to 10 nM, 2 nM to 5 nM, 2 nM to 3 nM, 3 nM to 10 nM, 3 nM to 5 nM, or 5 nM to 10 nM.
• In some embodiments, the natural ligand is a mammalian PDL1 or a mammalian PDL2. In some embodiments, the natural ligand is selected from the group consisting of: a human PDL1, a human PDL2, a cynomolgus monkey PDL1, and a cynomolgus monkey PDL2.
• In some embodiments, the activatable antibody has one or more of the following characteristics: (a) the AB induces type 1 diabetes in a non-obese diabetic (NOD) mouse; and (b) the activatable antibody in an uncleaved state inhibits the induction of type 1 diabetes in a NOD mouse.
• In some embodiments, the activatable antibody inhibits the induction of type 1 diabetes in the NOD mouse after administration of the activatable antibody at a single dose of 0.5 mg/kg to 15 mg/kg, 1 mg/kg to 15 mg/kg, 2 mg/kg to 15 mg/kg, 3 mg/kg to 15 mg/kg, 5 mg/kg to 15 mg/kg, 10 mg/kg to 15 mg/kg, 0.5 mg/kg to 10 mg/kg, 1 mg/kg to 10 mg/kg, 2 mg/kg to 10 mg/kg, 3 mg/kg to 10 mg/kg, 5 mg/kg to 10 mg/kg, 0.5 mg/kg to 5 mg/kg, 1 mg/kg to 5 mg/kg, 2 mg/kg to 5 mg/kg, 3 mg/kg to 5 mg/kg, 0.5 mg/kg to 3 mg/kg, 1 mg/kg to 3 mg/kg, 2 mg/kg to 3 mg/kg, 0.5 mg/kg to 2 mg/kg, 1 mg/kg to 2 mg/kg, or 0.5 mg/kg to 1 mg/kg. In some embodiments, the activatable antibody inhibits the induction of type 1 diabetes in the NOD mouse after administration of the activatable antibody at a single dose of 3 mg/kg to 10 mg/kg, 3 mg/kg or 10 mg/kg. In some embodiments, the activatable antibody inhibits the induction of type 1 diabetes in the NOD mouse after administration of the activatable antibody at a single dose of 3 mg/kg to 10 mg/kg. In some embodiments, the activatable antibody inhibits the induction of type 1 diabetes in the NOD mouse after administration of the activatable antibody at a single dose of 3 mg/kg. In some embodiments, the activatable antibody inhibits the induction of type 1 diabetes in the NOD mouse after administration of the activatable antibody at a single dose of 10 mg/kg.
• In some embodiments, the AB induces type 1 diabetes in the NOD mouse after administration of the AB at a single dose of 0.5 mg/kg to 15 mg/kg, 1 mg/kg to 15 mg/kg, 2 mg/kg to 15 mg/kg, 3 mg/kg to 15 mg/kg, 5 mg/kg to 15 mg/kg, 10 mg/kg to 15 mg/kg, 0.5 mg/kg to 10 mg/kg, 1 mg/kg to 10 mg/kg, 2 mg/kg to 10 mg/kg, 3 mg/kg to 10 mg/kg, 5 mg/kg to 10 mg/kg, 0.5 mg/kg to 5 mg/kg, 1 mg/kg to 5 mg/kg, 2 mg/kg to 5 mg/kg, 3 mg/kg to 5 mg/kg, 0.5 mg/kg to 3 mg/kg, 1 mg/kg to 3 mg/kg, 2 mg/kg to 3 mg/kg, 0.5 mg/kg to 2 mg/kg, 1 mg/kg to 2 mg/kg, or 0.5 mg/kg to 1 mg/kg. In some embodiments, the AB induces type 1 diabetes in the NOD mouse after administration of the AB at a single dose of 1 mg/kg to 20 mg/kg, 1 mg/kg, 3 mg/kg, 5 mg/kg, 10 mg/kg, or 20 mg/kg. In some embodiments, the AB induces type 1 diabetes in the NOD mouse after administration of the AB at a single dose of 1 mg/kg to 20 mg/kg. In some embodiments, the AB induces type 1 diabetes in the NOD mouse after administration of the AB at a single dose of 1 mg/kg. In some embodiments, the AB induces type 1 diabetes in the NOD mouse after administration of the AB at a single dose of 3 mg/kg. In some embodiments, the AB induces type 1 diabetes in the NOD mouse after administration of the AB at a single dose of 5 mg/kg. In some embodiments, the AB induces type 1 diabetes in the NOD mouse after administration of the AB at a single dose of 10 mg/kg. In some embodiments, the AB induces type 1 diabetes in the NOD mouse after administration of the AB at a single dose of 20 mg/kg.
• In some embodiments, the activatable antibody has one or more of the following characteristics: (a) the activatable antibody in an uncleaved state does not induce type 1 diabetes in greater than 50% of a population of non-obese diabetic (NOD) mice, and (b) the AB induces type 1 diabetes in greater than 50%, greater than 60%, greater than 70%, greater than 80%, between 50% to 100%, between 50% and 75%, or between 70% and 90% of a population of NOD mice.
• In some embodiments, the activatable antibody does not induce type 1 diabetes in greater than 50%, greater than 60%, greater than 70%, greater than 80%, between 50% to 100%, between 50% and 75%, or between 70% and 90% of the population of NOD mice after administration to each mouse in the population a single dose of the activatable antibody at a dosage of: 0.5 mg/kg to 15 mg/kg, 1 mg/kg to 15 mg/kg, 2 mg/kg to 15 mg/kg, 3 mg/kg to 15 mg/kg, 5 mg/kg to 15 mg/kg, 10 mg/kg to 15 mg/kg, 0.5 mg/kg to 10 mg/kg, 1 mg/kg to 10 mg/kg, 2 mg/kg to 10 mg/kg, 3 mg/kg to 10 mg/kg, 5 mg/kg to 10 mg/kg, 0.5 mg/kg to 5 mg/kg, 1 mg/kg to 5 mg/kg, 2 mg/kg to 5 mg/kg, 3 mg/kg to 5 mg/kg, 0.5 mg/kg to 3 mg/kg, 1 mg/kg to 3 mg/kg, 2 mg/kg to 3 mg/kg, 0.5 mg/kg to 2 mg/kg, 1 mg/kg to 2 mg/kg, or 0.5 mg/kg to 1 mg/kg. In some embodiments, the activatable antibody inhibits the induction of type 1 diabetes in the NOD mouse after administration of the activatable antibody at a single dose of 3 mg/kg to 10 mg/kg, 3 mg/kg or 10 mg/kg. In some embodiments the dose is a single dose of 3 mg/kg to 10 mg/kg. In some embodiments the dose is a single dose of 3 mg/kg. In some embodiments the dose is a single dose of 10 mg/kg.
• In some embodiments, the activatable antibody has one or more of the following characteristics: (a) the activatable antibody in an uncleaved state does not induce type 1 diabetes in greater than 50%, greater than 60%, greater than 70%, greater than 80%, between 50% to 100%, between 50% and 75%, or between 70% and 90% of a population of non-obese diabetic (NOD) mice when administered at a single dose of 3 mg/kg; and (b) the AB induces type 1 diabetes in greater than 50%, greater than 60%, greater than 70%, greater than 80%, between 50% to 100%, between 50% and 75%, or between 70% and 90% of a population of NOD mice, when administered at a single dose of 3 mg/kg.
• In some embodiments, the activatable antibody has one or more of the following characteristics: (a) the activatable antibody in an uncleaved state does not induce type 1 diabetes in greater than 50%, greater than 60%, greater than 70%, greater than 80%, between 50% to 100%, between 50% and 75%, or between 70% and 90% of a population of non-obese diabetic (NOD) mice when administered at a single dose of 10 mg/kg; and (b) the AB induces type 1 diabetes in greater than 50%, greater than 60%, greater than 70%, greater than 80%, between 50% to 100%, between 50% and 75%, or between 70% and 90% of a population of NOD mice, when administered at a single dose of 10 mg/kg.
• In some embodiments, the AB induces type 1 diabetes in greater than 50%, greater than 60%, greater than 70%, greater than 80%, between 50% to 100%, between 50% and 75%, or between 70% and 90% of the population of the NOD mice after administration to each mouse in the population a single dose of the AB at a dosage of: 2 mg/kg to 15 mg/kg, 3 mg/kg to 15 mg/kg, 5 mg/kg to 15 mg/kg, 10 mg/kg to 15 mg/kg, 2 mg/kg to 10 mg/kg, 3 mg/kg to 10 mg/kg, 5 mg/kg to 10 mg/kg, 2 mg/kg to 5 mg/kg, 3 mg/kg to 5 mg/kg, or 2 mg/kg to 3 mg/kg. In some embodiments the dose is a single dose of 3 mg/kg to 20 mg/kg, 3 mg/kg, 5 mg/kg, 10 mg/kg, or 20 mg/kg. In some embodiments the dose is a single dose of 3 mg/kg to 20 mg/kg. In some embodiments the dose is a single dose of 3 mg/kg. In some embodiments the dose is a single dose of 5 mg/kg. In some embodiments the dose is a single dose of 10 mg/kg. In some embodiments the dose is a single dose of 20 mg/kg.
• In some embodiments, the activatable antibody in an uncleaved state does not induce type 1 diabetes in greater than 50% of a population of non-obese diabetic (NOD) mice, wherein the population of NOD mice are concurrently dosed with an anti-CTLA4 antibody.
• In some embodiments, the population of NOD mice are each administered a single dose of the activatable antibody at a dosage of 2 mg/kg to 15 mg/kg, 3 mg/kg to 15 mg/kg, 5 mg/kg to 15 mg/kg, 10 mg/kg to 15 mg/kg, 2 mg/kg to 10 mg/kg, 3 mg/kg to 10 mg/kg, 5 mg/kg to 10 mg/kg, 2 mg/kg to 5 mg/kg, 3 mg/kg to 5 mg/kg, or 2 mg/kg to 3 mg/kg concurrently with a dose of an anti-CTLA4 antibody. In some embodiments, the population of NOD mice are each administered a single dose of the activatable antibody at a dosage of 10 mg/kg concurrently with a dose of an anti-CTLA4 antibody.
• In some embodiments, the population of NOD mice is each administered a single dose of the anti-CTLA4 antibody at a dosage of 2 mg/kg to 15 mg/kg, 3 mg/kg to 15 mg/kg, 5 mg/kg to 15 mg/kg, or 10 mg/kg to 15 mg/kg concurrently with a dose of an anti-PD-1 activatable antibody. In some embodiments, the population of NOD mice is each administered a single dose of the anti-CTLA4 antibody at a dosage of 10 mg/kg concurrently with a dose of an anti-PD-1 activatable antibody.
• In some embodiments, the population of NOD mice is each administered a single dose of the activatable antibody at a dosage of 5 mg/kg to 15 mg/kg and a single dose of the anti-CTLA4 antibody at a dosage of 5 mg/kg to 15 mg/kg. In some embodiments, the population of NOD mice is each administered a single dose of the activatable antibody at a dosage of 10 mg/kg concurrently with a single dose of an anti-CTLA4 antibody at a dosage of 10 mg/kg.
• In some embodiments, the NOD mouse is a female NOD/ShiLtJ mouse substrain. In some embodiments, the population of NOD mice is each 5 weeks old when the activatable antibody is first administered. In some embodiments, the population of NOD mice is each 10 weeks old when the activatable antibody is first administered.
• The activatable antibodies in an activated state bind PD-1 and include (i) an antibody or an antigen binding fragment thereof (AB) that specifically binds to PD-1; (ii) a masking moiety (MM) that, when the activatable antibody is in an uncleaved state, inhibits the binding of the AB to PD-1; and (c) a cleavable moiety (CM) coupled to the AB, wherein the CM is a polypeptide that functions as a substrate for a protease.
• In some embodiments, the activatable antibody in the uncleaved state has the structural arrangement from N-terminus to C-terminus as follows: MM-CM-AB or AB-CM-MM.
• In some embodiments, the activatable antibody comprises a linking peptide between the MM and the CM.
• In some embodiments, the activatable antibody comprises a linking peptide between the CM and the AB.
• In some embodiments, the activatable antibody comprises a first linking peptide (LP1) and a second linking peptide (LP2), and wherein the activatable antibody in the uncleaved state has the structural arrangement from N-terminus to C-terminus as follows: MM-LP1-CM-LP2-AB or AB-LP2-CM-LP1-MM. In some embodiments, the two linking peptides need not be identical to each other. In some embodiments, each of LP1 and LP2 is a peptide of about 1 to 20 amino acids in length.
• In some embodiments, at least one of LP1 or LP2 comprises an amino acid sequence selected from the group consisting of (GS)_n, (GGS)_n, (GSGGS)_n (SEQ ID NO: 363) and (GGGS)_n (SEQ ID NO: 364), where n is an integer of at least one.
• In some embodiments, at least one of LP1 or LP2 comprises an amino acid sequence selected from the group consisting of GGSG (SEQ ID NO: 365), GGSGG (SEQ ID NO: 366), GSGSG (SEQ ID NO: 367), GSGGG (SEQ ID NO: 368), GGGSG (SEQ ID NO: 369), and GSSSG (SEQ ID NO: 370).
• In some embodiments, LP1 comprises the amino acid sequence GSSGGSGGSGGSG (SEQ ID NO: 371), GSSGGSGGSGG (SEQ ID NO: 372), GSSGGSGGSGGS (SEQ ID NO: 373), GSSGGSGGSGGSGGGS (SEQ ID NO: 374), GSSGGSGGSG (SEQ ID NO: 375), GSSGGSGGSGS (SEQ ID NO: 376), GGGSSGGS (SEQ ID NO: 65), or GGGSSGG (SEQ ID NO: 1040).
• In some embodiments, LP2 comprises the amino acid sequence GSS, GGS, GGGS (SEQ ID NO: 377), GSSGT (SEQ ID NO: 378) or GSSG (SEQ ID NO: 379).
• In some embodiments, the AB has a dissociation constant (K_d) of about 100 nM or less for binding to PD-1.
• In some embodiments, the activatable antibody includes an antibody or antigen-binding fragment thereof (AB) that specifically binds PD-1. In some embodiments, the antibody or antigen-binding fragment thereof that binds PD-1 is a monoclonal antibody, domain antibody, single chain, Fab fragment, a F(ab′)₂ fragment, a scFv, a scAb, a dAb, a single domain heavy chain antibody, or a single domain light chain antibody. In some embodiments, such an antibody or antigen-binding fragment thereof that binds PD-1 is a mouse, other rodent, chimeric, humanized or fully human monoclonal antibody.
• In some embodiments, the activatable antibody comprises a heavy chain amino acid sequence that comprises or is derived from an amino acid sequence selected from the group consisting of SEQ ID NO: 1, 5, 9, 13, 17, 21, 23, 25, 27, 29, 31, 33, 35, and 37. In some embodiments, the activatable antibody comprises a light chain amino acid sequence selected from the group consisting of SEQ ID NO: 3, 7, 11, 15, 19, 39, 41, 43, 45, 47, 49, 51, 53, 55, 57, and 59.
• In some embodiments, the activatable anti-PD-1 antibody includes a heavy chain that comprises or is derived from an amino acid sequence selected from the group consisting of SEQ ID NO: 21, 23, 25, 27, 29, 31, 33, 35, and 37, and a light chain that comprises or is derived from an amino acid sequence selected from the group consisting of SEQ ID NO: 39, 41, 43, 45, 47, 49, 51, 53, 55, 57, and 59.
• In some embodiments, the activatable anti-PD-1 antibody includes a heavy chain that comprises or is derived from amino acid sequence SEQ ID NO: 21. In some embodiments, the activatable anti-PD-1 antibody includes a light chain that comprises or is derived from amino acid sequence SEQ ID NO: 45 or SEQ ID NO: 47. In some embodiments, the activatable anti-PD-1 antibody includes a heavy chain that comprises or is derived from amino acid sequence SEQ ID NO: 21 and a light chain that comprises or is derived from amino acid sequence SEQ ID NO: 45 or SEQ ID NO: 47. In some embodiments, the activatable anti-PD-1 antibody includes a heavy chain that comprises or is derived from amino acid sequence SEQ ID NO: 21 and a light chain that comprises or is derived from amino acid sequence SEQ ID NO: 45. In some embodiments, the activatable anti-PD-1 antibody includes a heavy chain that comprises or is derived from amino acid sequence SEQ ID NO: 21 and a light chain that comprises or is derived from amino acid sequence SEQ ID NO: 47.
• In some embodiments, the activatable anti-PD-1 antibody includes the combination of the complementarity determining region (CDR) sequences of the heavy chain amino acid sequence of SEQ ID NO: 21. In some embodiments, the activatable anti-PD-1 antibody includes the combination of the CDR sequences of the light chain amino acid sequence of SEQ ID NO: 45 or of SEQ ID NO: 47. In some embodiments, the activatable anti-PD-1 antibody includes a combination of the CDR sequences of the heavy chain amino acid sequence of SEQ ID NO: 21, and the CDR sequences of the light chain amino acid sequence of SEQ ID NO: 45 or 47. In some embodiments, the activatable anti-PD-1 antibody includes a combination of the CDR sequences of the heavy chain amino acid sequence of SEQ ID NO: 21, and the CDR sequences of the light chain amino acid sequence of SEQ ID NO: 45. In some embodiments, the activatable anti-PD-1 antibody includes a combination of the CDR sequences of the heavy chain amino acid sequence of SEQ ID NO: 21, and the CDR sequences of the light chain amino acid sequence of SEQ ID NO: 47.
• In some embodiments, the activatable anti-PD-1 antibody includes: (a) a variable heavy chain complementarity determining region 1 (VH CDR1) comprising an amino acid sequence selected from the group consisting of SEQ ID NOs: 653-657; (b) a variable heavy chain complementarity determining region 2 (VH CDR2) comprising an amino acid sequence selected from the group consisting of SEQ ID NOs: 658-663; (c) a variable heavy chain complementarity determining region 3 (VH CDR3) comprising an amino acid sequence selected from the group consisting of SEQ ID NOs: 664-668; (d) a variable light chain complementarity determining region 1 (VL CDR1) comprising an amino acid sequence selected from the group consisting of SEQ ID NOs: 669-677; (e) a variable light chain complementarity determining region 2 (VL CDR2) comprising an amino acid sequence selected from the group consisting of SEQ ID NOs: 678-682; and (f) variable light chain complementarity determining region 3 (VL CDR3) comprising an amino acid sequence selected from the group consisting of SEQ ID NOs: 683-687.
• In some embodiments, the activatable anti-PD-1 antibody includes a combination of a variable heavy chain complementarity determining region 1 (VH CDR1, also referred to herein as CDRH1) sequence, a variable heavy chain complementarity determining region 2 (VH CDR2, also referred to herein as CDRH2) sequence, and a variable heavy chain complementarity determining region 3 (VH CDR3, also referred to herein as CDRH3) sequence, wherein the VH CDR1 sequence comprises GFTFSGYAMS (SEQ ID NO: 653); the VH CDR2 sequence comprises YISNSGGNAH (SEQ ID NO: 658); and the VH CDR3 sequence comprises EDYGTSPFVY (SEQ ID NO: 664).
• In some embodiments, the activatable anti-PD-1 antibody includes a combination of a variable light chain complementarity determining region 1 (VL CDR1, also referred to herein as CDRL1) sequence, a variable light chain complementarity determining region 2 (VL CDR2, also referred to herein as CDRL2) sequence, and a variable light chain complementarity determining region 3 (VL CDR3, also referred to herein as CDRL3) sequence, wherein the VL CDR1 sequence comprises RASESVDSYGISFMN (SEQ ID NO: 675) or RASESVDAYGISFMN (SEQ ID NO:676); the VL CDR2 sequence comprises AASNQGS (SEQ ID NO: 678); and the VL CDR3 sequence comprises QQSKDVPWT (SEQ ID NO: 683). In some embodiments, the activatable anti-PD-1 antibody includes a combination of a VL CDR1 sequence, a VL CDR2 sequence, and a VL CDR3 sequence, wherein the VL CDR1 sequence comprises RASESVDSYGISFMN (SEQ ID NO: 675); the VL CDR2 sequence comprises AASNQGS (SEQ ID NO: 678); and the VL CDR3 sequence comprises QQSKDVPWT (SEQ ID NO: 683). In some embodiments, the activatable anti-PD-1 antibody includes a combination of a VL CDR1 sequence, a VL CDR2 sequence, and a VL CDR3 sequence, wherein the VL CDR1 sequence comprises RASESVDAYGISFMN (SEQ ID NO:676); the VL CDR2 sequence comprises AASNQGS (SEQ ID NO: 678); and the VL CDR3 sequence comprises QQSKDVPWT (SEQ ID NO: 683).
• In some embodiments, the activatable anti-PD-1 antibody includes a combination of a VH CDR1 sequence, a VH CDR2 sequence, a VH CDR3 sequence, a VL CDR1 sequence, a VL CDR2 sequence, and a VL CDR3 sequence, wherein the VH CDR1 sequence comprises GFTFSGYAMS (SEQ ID NO: 653); the VH CDR2 sequence comprises YISNSGGNAH (SEQ ID NO: 658); and the VH CDR3 sequence comprises EDYGTSPFVY (SEQ ID NO: 664); the VL CDR1 sequence comprises RASESVDSYGISFMN (SEQ ID NO: 675) or RASESVDAYGISFMN (SEQ ID NO:676); the VL CDR2 sequence comprises AASNQGS (SEQ ID NO: 678); and the VL CDR3 sequence comprises QQSKDVPWT (SEQ ID NO: 683). In some embodiments, the activatable anti-PD-1 antibody includes a combination of a VH CDR1 sequence, a VH CDR2 sequence, a VH CDR3 sequence, a VL CDR1 sequence, a VL CDR2 sequence, and a VL CDR3 sequence, wherein the VH CDR1 sequence comprises GFTFSGYAMS (SEQ ID NO: 653); the VH CDR2 sequence comprises YISNSGGNAH (SEQ ID NO: 658); and the VH CDR3 sequence comprises EDYGTSPFVY (SEQ ID NO: 664); the VL CDR1 sequence comprises RASESVDSYGISFMN (SEQ ID NO: 675); the VL CDR2 sequence comprises AASNQGS (SEQ ID NO: 678); and the VL CDR3 sequence comprises QQSKDVPWT (SEQ ID NO: 683). In some embodiments, the activatable anti-PD-1 antibody includes a combination of a VH CDR1 sequence, a VH CDR2 sequence, a VH CDR3 sequence, a VL CDR1 sequence, a VL CDR2 sequence, and a VL CDR3 sequence, wherein the VH CDR1 sequence comprises GFTFSGYAMS (SEQ ID NO: 653); the VH CDR2 sequence comprises YISNSGGNAH (SEQ ID NO: 658); and the VH CDR3 sequence comprises EDYGTSPFVY (SEQ ID NO: 664); the VL CDR1 sequence comprises RASESVDAYGISFMN (SEQ ID NO:676); the VL CDR2 sequence comprises AASNQGS (SEQ ID NO: 678); and the VL CDR3 sequence comprises QQSKDVPWT (SEQ ID NO: 683).
• In some embodiments, the activatable anti-PD-1 antibody includes a heavy chain that comprises or is derived from the amino acid sequence of SEQ ID NO: 1346, and a light chain that comprises or is derived from the amino acid sequence of SEQ ID NO: 626.
• In some embodiments, the activatable anti-PD-1 antibody includes a heavy chain that comprises or is derived from the amino acid sequence of SEQ ID NO: 1514, and a light chain that comprises or is derived from the amino acid sequence of SEQ ID NO: 638.
• In some embodiments, the activatable anti-PD-1 antibody includes the combination of the complementarity determining region (CDR) sequences of the heavy chain amino acid sequence of SEQ ID NO: 1346. In some embodiments, the activatable anti-PD-1 antibody includes the combination of the CDR sequences of the light chain amino acid sequence of SEQ ID NO: 626. In some embodiments, the activatable anti-PD-1 antibody includes a combination of the CDR sequences of the heavy chain amino acid sequence of SEQ ID NO: 1346, and the CDR sequences of the light chain amino acid sequence of SEQ ID NO: 626.
• In some embodiments, the activatable anti-PD-1 antibody includes a combination of a variable heavy chain complementarity determining region 1 (VH CDR1, also referred to herein as CDRH1) sequence, a variable heavy chain complementarity determining region 2 (VH CDR2, also referred to herein as CDRH2) sequence, and a variable heavy chain complementarity determining region 3 (VH CDR3, also referred to herein as CDRH3) sequence, wherein the VH CDR1 sequence comprises GITFSNSG (SEQ ID NO: 1705); the VH CDR2 sequence comprises IWYDGSKR (SEQ ID NO: 1706); and the VH CDR3 sequence comprises TNDDY (SEQ ID NO: 1707).
• In some embodiments, the activatable anti-PD-1 antibody includes a combination of a variable light chain complementarity determining region 1 (VL CDR1, also referred to herein as CDRL1) sequence, a variable light chain complementarity determining region 2 (VL CDR2, also referred to herein as CDRL2) sequence, and a variable light chain complementarity determining region 3 (VL CDR3, also referred to herein as CDRL3) sequence, wherein the VL CDR1 sequence comprises QSVSSY (SEQ ID NO: 1708); the VL CDR2 sequence comprises DAS (SEQ ID NO: 1709); and the VL CDR3 sequence comprises QQSSNWPRT (SEQ ID NO: 1710).
• In some embodiments, the activatable anti-PD-1 antibody includes a combination of a VH CDR1 sequence, a VH CDR2 sequence, a VH CDR3 sequence, a VL CDR1 sequence, a VL CDR2 sequence, and a VL CDR3 sequence, wherein the VH CDR1 sequence comprises GITFSNSG (SEQ ID NO: 1705); the VH CDR2 sequence comprises IWYDGSKR (SEQ ID NO: 1706); the VH CDR3 sequence comprises TNDDY (SEQ ID NO: 1707); the VL CDR1 sequence comprises QSVSSY (SEQ ID NO: 1708); the VL CDR2 sequence comprises DAS (SEQ ID NO: 1709); and the VL CDR3 sequence comprises QQSSNWPRT (SEQ ID NO: 1710).
• In some embodiments, the activatable anti-PD-1 antibody includes the combination of the complementarity determining region (CDR) sequences of the heavy chain amino acid sequence of SEQ ID NO: 1514. In some embodiments, the activatable anti-PD-1 antibody includes the combination of the CDR sequences of the light chain amino acid sequence of SEQ ID NO: 638. In some embodiments, the activatable anti-PD-1 antibody includes a combination of the CDR sequences of the heavy chain amino acid sequence of SEQ ID NO: 1514, and the CDR sequences of the light chain amino acid sequence of SEQ ID NO: 638.
• In some embodiments, the activatable anti-PD-1 antibody includes a combination of a variable heavy chain complementarity determining region 1 (VH CDR1, also referred to herein as CDRH1) sequence, a variable heavy chain complementarity determining region 2 (VH CDR2, also referred to herein as CDRH2) sequence, and a variable heavy chain complementarity determining region 3 (VH CDR3, also referred to herein as CDRH3) sequence, wherein the VH CDR1 sequence comprises GYTFTNYY (SEQ ID NO: 1711); the VH CDR2 sequence comprises INPSNGGT (SEQ ID NO: 1712); and the VH CDR3 sequence comprises RRDYRFDMGFDY (SEQ ID NO: 1713).
• In some embodiments, the activatable anti-PD-1 antibody includes a combination of a variable light chain complementarity determining region 1 (VL CDR1, also referred to herein as CDRL1) sequence, a variable light chain complementarity determining region 2 (VL CDR2, also referred to herein as CDRL2) sequence, and a variable light chain complementarity determining region 3 (VL CDR3, also referred to herein as CDRL3) sequence, wherein the VL CDR1 sequence comprises KGVSTSGYSY (SEQ ID NO: 1714); the VL CDR2 sequence comprises LAS (SEQ ID NO: 1715); and the VL CDR3 sequence comprises QHSRDLPLT (SEQ ID NO: 1716).
• In some embodiments, the activatable anti-PD-1 antibody includes a combination of a VH CDR1 sequence, a VH CDR2 sequence, a VH CDR3 sequence, a VL CDR1 sequence, a VL CDR2 sequence, and a VL CDR3 sequence, wherein the VH CDR1 sequence comprises GYTFTNYY (SEQ ID NO: 1711); the VH CDR2 sequence comprises INPSNGGT (SEQ ID NO: 1712); the VH CDR3 sequence comprises RRDYRFDMGFDY (SEQ ID NO: 1713); the VL CDR1 sequence comprises KGVSTSGYSY (SEQ ID NO: 1714); the VL CDR2 sequence comprises LAS (SEQ ID NO: 1715); and the VL CDR3 sequence comprises QHSRDLPLT (SEQ ID NO: 1716).
• In some embodiments, the activatable antibody comprises a heavy chain amino acid sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to an amino acid sequence selected from the group consisting of SEQ ID NO: 1, 5, 9, 13, 17, 21, 23, 25, 27, 29, 31, 33, 35, and 37. In some embodiments, the activatable antibody comprises a light chain amino acid that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to an amino acid sequence amino acid sequence selected from the group consisting of SEQ ID NO: 3, 7, 11, 15, 19, 39, 41, 43, 45, 47, 49, 51, 53, 55, 57, and 59. In some embodiments, the activatable antibody comprises a heavy chain amino acid sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to an amino acid sequence selected from the group consisting of SEQ ID NO: 1, 5, 9, 13, 17, 21, 23, 25, 27, 29, 31, 33, 35, and 37, and a light chain amino acid that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to an amino acid sequence amino acid sequence selected from the group consisting of SEQ ID NO: 3, 7, 11, 15, 19, 39, 41, 43, 45, 47, 49, 51, 53, 55, 57, and 59.
• In some embodiments, the activatable antibody comprises a heavy chain amino acid sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to an amino acid sequence selected from the group consisting of SEQ ID NO: 21, 23, 25, 27, 29, 31, 33, 35, and 37. In some embodiments, the activatable antibody comprises a light chain amino acid that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to an amino acid sequence amino acid sequence selected from the group consisting of SEQ ID NO: 39, 41, 43, 45, 47, 49, 51, 53, 55, 57, and 59. In some embodiments, the activatable antibody comprises a heavy chain amino acid sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to an amino acid sequence selected from the group consisting of SEQ ID NO: 21, 23, 25, 27, 29, 31, 33, 35, and 37, and a light chain amino acid that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to an amino acid sequence amino acid sequence selected from the group consisting of SEQ ID NO: 39, 41, 43, 45, 47, 49, 51, 53, 55, 57, and 59. In some embodiments, the activatable anti-PD-1 antibody includes a heavy chain sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to the amino acid sequence of SEQ ID NO: 21, and a light chain sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to the amino acid sequence of SEQ ID NO: 45 or SEQ ID NO: 47. In some embodiments, the activatable anti-PD-1 antibody includes a heavy chain sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to the amino acid sequence of SEQ ID NO: 21, and a light chain sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to the amino acid sequence of SEQ ID NO: 45. In some embodiments, the activatable anti-PD-1 antibody includes a heavy chain sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to the amino acid sequence of SEQ ID NO: 21, and a light chain sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to the amino acid sequence of SEQ ID NO: 47.
• In some embodiments, the activatable anti-PD-1 antibody includes a heavy chain sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to the amino acid sequence of SEQ ID NO: 1346, and a light chain sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to the amino acid sequence of SEQ ID NO: 626.
• In some embodiments, the activatable anti-PD-1 antibody includes a heavy chain sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to the amino acid sequence of SEQ ID NO: 1514, and a light chain sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to the amino acid sequence of SEQ ID NO: 638.
• In some embodiments, the AB of the activatable anti-PD-1 antibody comprises a heavy chain amino acid sequence selected from the group consisting of the heavy chain sequences shown in Table 7. In some embodiments, the AB of the activatable anti-PD-1 antibody comprises a light chain amino acid sequence selected from the group consisting of the light chain sequences shown in Table 7. In some embodiments, the AB of the activatable anti-PD-1 antibody comprises a heavy chain amino acid sequence selected from the group consisting of the heavy chain sequences shown in Table 7 and a light chain amino acid sequence selected from the group consisting of the light chain sequences shown in Table 7.
• In some embodiments, the AB of the activatable anti-PD-1 antibody comprises a heavy chain amino acid sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to an amino acid sequence selected from the group consisting of the heavy chain sequences shown in Table 7. In some embodiments, the AB of the activatable anti-PD-1 antibody comprises a light chain amino acid sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to an amino acid sequence selected from the group consisting of the light chain sequences shown in Table 7. In some embodiments, the AB of the activatable anti-PD-1 antibody comprises a heavy chain amino acid sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to an amino acid sequence selected from the group consisting of the heavy chain sequences shown in Table 7 and a light chain amino acid sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to an amino acid sequence selected from the group consisting of the light chain sequences shown in Table 7.
• In some embodiments, the AB of the activatable antibody includes a combination of a VH CDR1 sequence, a VH CDR2 sequence, and a VH CDR3 sequence, wherein the VH CDR1 sequence comprises a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to GITFSNSG (SEQ ID NO: 1705); the VH CDR2 sequence comprises a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to IWYDGSKR (SEQ ID NO: 1706); and the VH CDR3 sequence comprises a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to TNDDY (SEQ ID NO: 1707).
• In some embodiments, the AB of the activatable antibody includes a combination of a VL CDR1 sequence, a VL CDR2 sequence, and a VL CDR3 sequence, wherein the VL CDR1 sequence comprises a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to QSVSSY (SEQ ID NO: 1708); the VL CDR2 sequence comprises a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to DAS (SEQ ID NO: 1709); and the VL CDR3 sequence comprises a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to QQSSNWPRT (SEQ ID NO: 1710).
• In some embodiments, the AB of the activatable antibody includes a combination of a VH CDR1 sequence, a VH CDR2 sequence, a VH CDR3 sequence, a VL CDR1 sequence, a VL CDR2 sequence, and a VL CDR3 sequence, wherein the VH CDR1 sequence comprises a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to GITFSNSG (SEQ ID NO: 1705); the VH CDR2 sequence comprises a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to IWYDGSKR (SEQ ID NO: 1706); the VH CDR3 sequence comprises a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to TNDDY (SEQ ID NO: 1707); the VL CDR1 sequence comprises a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to QSVSSY (SEQ ID NO: 1708); the VL CDR2 sequence comprises a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to DAS (SEQ ID NO: 1709); and the VL CDR3 sequence comprises a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to QQSSNWPRT (SEQ ID NO: 1710).
• In some embodiments, the AB of the activatable antibody includes a combination of a VH CDR1 sequence, a VH CDR2 sequence, and a VH CDR3 sequence, wherein the VH CDR1 sequence comprises a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to GYTFTNYY (SEQ ID NO: 1711); the VH CDR2 sequence comprises a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to INPSNGGT (SEQ ID NO: 1712); and the VH CDR3 sequence comprises a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to RRDYRFDMGFDY (SEQ ID NO: 1713).
• In some embodiments, the AB of the activatable antibody includes a combination of a VL CDR1 sequence, a VL CDR2 sequence, and a VL CDR3 sequence, wherein the VL CDR1 sequence comprises a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to KGVSTSGYSY (SEQ ID NO: 1714); the VL CDR2 sequence comprises a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to LAS (SEQ ID NO: 1715); and the VL CDR3 sequence comprises a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to QHSRDLPLT (SEQ ID NO: 1716).
• In some embodiments, the AB of the activatable antibody includes a combination of a VH CDR1 sequence, a VH CDR2 sequence, a VH CDR3 sequence, a VL CDR1 sequence, a VL CDR2 sequence, and a VL CDR3 sequence, wherein the VH CDR1 sequence comprises a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to GYTFTNYY (SEQ ID NO: 1711); the VH CDR2 sequence comprises a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to INPSNGGT (SEQ ID NO: 1712); the VH CDR3 sequence comprises a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to RRDYRFDMGFDY (SEQ ID NO: 1713); the VL CDR1 sequence comprises a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to KGVSTSGYSY (SEQ ID NO: 1714); the VL CDR2 sequence comprises a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to LAS (SEQ ID NO: 1715); and the VL CDR3 sequence comprises a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to QHSRDLPLT (SEQ ID NO: 1716).
• In some embodiments, the activatable antibody comprises a combination of a variable heavy chain complementarity determining region 1 (VH CDR1, also referred to herein as CDRH1) sequence, a variable heavy chain complementarity determining region 2 (VH CDR2, also referred to herein as CDRH2) sequence, a variable heavy chain complementarity determining region 3 (VH CDR3, also referred to herein as CDRH3) sequence, a variable light chain complementarity determining region 1 (VL CDR1, also referred to herein as CDRL1) sequence, a variable light chain complementarity determining region 2 (VL CDR2, also referred to herein as CDRL2) sequence, and a variable light chain complementarity determining region 3 (VL CDR3, also referred to herein as CDRL3) sequence, wherein at least one CDR sequence is selected from the group consisting of a VH CDR1 sequence shown in Table 8; a VH CDR2 sequence shown in Table 8; a VH CDR3 sequence shown in Table 8; a VL CDR1 sequence shown in Table 8; a VL CDR2 sequence shown in Table 8; and a VL CDR3 sequence shown in Table 8.
• In some embodiments, the activatable antibody comprises a combination of a VH CDR1 sequence, a VH CDR2 sequence, a VH CDR3 sequence, a VL CDR1 sequence, a VL CDR2 sequence, and a VL CDR3 sequence, wherein at least one CDR sequence is selected from the group consisting of a VH CDR1 sequence that includes a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to a VH CDR1 sequence shown in Table 8; a VH CD2 sequence that includes a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to a VH CDR2 sequence shown in Table 8; a VH CDR3 sequence that includes a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to a VH CDR3 sequence shown in Table 8; a VL CDR1 sequence that includes a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to a VL CDR1 sequence shown in Table 8; a VL CDR2 sequence that includes a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to a VL CDR2 sequence shown in Table 8; and a VL CDR3 sequence that includes a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to a VL CDR3 sequence shown in Table 8.
• In some embodiments, the activatable antibody comprises a combination of a VH CDR1 sequence, a VH CDR2 sequence, a VH CDR3 sequence shown in a single row in Table 8, and a VL CDR1 sequence, a VL CDR2 sequence, and a VL CDR3 sequence shown in a single row in Table 8.
• In some embodiments, the antibody comprises a heavy chain that comprises a combination of a VH CDR1 sequence, a VH CDR2 sequence, and a VH CDR3 sequence, wherein the combination is a combination of the three heavy chain CDR sequences (VH CDR1, VH CDR2, VH CDR3) shown in a single row in Table 8.
• In some embodiments, the activatable antibody comprises a combination of a VH CDR1 sequence, a VH CDR2 sequence, a VH CDR3 sequence shown in a single row in Table 8, a VL CDR1 sequence, a VL CDR2 sequence, and a VL CDR3 sequence shown in a single row in Table 8, wherein each CDR sequence in the combination comprises a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to the corresponding CDR sequence in a combination of the three VH CDR sequences (VH CDR1, VH CDR2, VH CDR3) shown in a single row in Table 8 and in a combination of the three VL CDR sequences (VL CDR1, VL CDR2, and VL CDR3) shown in a single row in Table 8.
• In some embodiments, the antibody comprises a heavy chain that comprises a combination of a VH CDR1 sequence, a VH CDR2 sequence, and a VH CDR3 sequence, wherein each CDR sequence in the combination comprises a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to the corresponding CDR sequence in a combination of three heavy chain CDR sequences (VH CDR1, VH CDR2, VH CDR3) shown in a single row in Table 8.
• In some embodiments, the activatable antibody comprises a combination of a variable heavy chain complementarity determining region 1 (VH CDR1, also referred to herein as CDRH1) sequence, a variable heavy chain complementarity determining region 2 (VH CDR2, also referred to herein as CDRH2) sequence, a variable heavy chain complementarity determining region 3 (VH CDR3, also referred to herein as CDRH3) sequence, a variable light chain complementarity determining region 1 (VL CDR1, also referred to herein as CDRL1) sequence, a variable light chain complementarity determining region 2 (VL CDR2, also referred to herein as CDRL2) sequence, and a variable light chain complementarity determining region 3 (VL CDR3, also referred to herein as CDRL3) sequence, wherein at least one CDR sequence is selected from the group consisting of a VH CDR1 sequence shown in Table 9; a VH CDR2 sequence shown in Table 9; a VH CDR3 sequence shown in Table 9; a VL CDR1 sequence shown in Table 9; a VL CDR2 sequence shown in Table 9; and a VL CDR3 sequence shown in Table 9.
• In some embodiments, the activatable antibody comprises a combination of a VH CDR1 sequence, a VH CDR2 sequence, a VH CDR3 sequence, a VL CDR1 sequence, a VL CDR2 sequence, and a VL CDR3 sequence, wherein at least one CDR sequence is selected from the group consisting of a VH CDR1 sequence that includes a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to a VH CDR1 sequence shown in Table 9; a VH CD2 sequence that includes a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to a VH CDR2 sequence shown in Table 9; a VH CDR3 sequence that includes a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to a VH CDR3 sequence shown in Table 9; a VL CDR1 sequence that includes a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to a VL CDR1 sequence shown in Table 9; a VL CDR2 sequence that includes a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to a VL CDR2 sequence shown in Table 9; and a VL CDR3 sequence that includes a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to a VL CDR3 sequence shown in Table 9.
• In some embodiments, the activatable antibody comprises a combination of a VH CDR1 sequence, a VH CDR2 sequence, a VH CDR3 sequence, a VL CDR1 sequence, a VL CDR2 sequence, and a VL CDR3 sequence, wherein the combination is a combination shown in Table 9.
• In some embodiments, the activatable antibody comprises a combination of a VH CDR1 sequence, a VH CDR2 sequence, a VH CDR3 sequence, a VL CDR1 sequence, a VL CDR2 sequence, and a VL CDR3 sequence, wherein each CDR sequence in the combination comprises a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to the corresponding CDR sequence in a combination shown in Table 9.
• In some embodiments, the activatable antibody comprises a masking moiety (MM) comprising an amino acid sequence selected from the group consisting of SEQ ID NOs: 66, 67, 70, 71, 74, 77, 81, 82, 84, 90, 91, 93, 99; a cleavable moiety (CM) comprising an amino acid sequence selected from the group consisting of SEQ ID NOs: 214, 294, 300, 302, 303, 305, 308, 318, 347, 361, 1092-1102, 1111, and 1157; and a combination of a VH CDR1 sequence, a VH CDR2 sequence, a VH CDR3 sequence, a VL CDR1 sequence, a VL CDR2 sequence, and a VL CDR3 sequence, wherein the combination comprises the VL CDR1 sequence of SEQ ID NO: 675 or SEQ ID NO: 676; the VL CDR2 sequence of SEQ ID NO: 678; the VL CDR3 sequence of SEQ ID NO: 683; the VH CDR1 sequence of SEQ ID NO: 653; the VH CDR2 sequence of SEQ ID NO: 658; and the VH CDR3 sequence of SEQ ID NO: 664.
• In some embodiments, the activatable antibody comprises a masking moiety (MM) comprising an amino acid sequence selected from the group consisting of SEQ ID NOs: 66, 67, 70, 71, 74, 77, 81, 82, 84, 90, 91, 93, 99; a cleavable moiety; a cleavable moiety (CM) comprising an amino acid sequence selected from the group consisting of SEQ ID NOs: 214, 294, 300, 302, 303, 305, 308, 318, 347, 361, 1092-1102, 1111, and 1157; a combination of a VH CDR1 sequence, a VH CDR2 sequence, a VH CDR3 sequence, a VL CDR1 sequence, a VL CDR2 sequence, and a VL CDR3 sequence, wherein the combination comprises the VL CDR1 sequence of SEQ ID NO: 675 or SEQ ID NO: 676; the VL CDR2 sequence of SEQ ID NO: 678; the VL CDR3 sequence of SEQ ID NO: 683; the VH CDR1 sequence of SEQ ID NO: 653; the VH CDR2 sequence of SEQ ID NO: 658; and the VH CDR3 sequence of SEQ ID NO: 664, and a human immunoglobulin light chain constant domain. In some embodiments, the human immunoglobulin light chain constant domain is a human kappa constant domain comprising SEQ ID NO: 61 or SEQ ID NO: 1344.
• In some embodiments, the activatable antibody comprises a masking moiety (MM) comprising an amino acid sequence selected from the group consisting of SEQ ID NOs: 66, 67, 70, 71, 74, 77, 81, 82, 84, 90, 91, 93, 99; a cleavable moiety (CM) comprising an amino acid sequence selected from the group consisting of SEQ ID NOs: 214, 294, 300, 302, 303, 305, 308, 318, 347, 361, 1092-1102, 1111, and 1157; a combination of a VH CDR1 sequence, a VH CDR2 sequence, a VH CDR3 sequence, a VL CDR1 sequence, a VL CDR2 sequence, and a VL CDR3 sequence, wherein the combination comprises the VL CDR1 sequence of SEQ ID NO: 675 or SEQ ID NO: 676; the VL CDR2 sequence of SEQ ID NO: 678; the VL CDR3 sequence of SEQ ID NO: 683; the VH CDR1 sequence of SEQ ID NO: 653; the VH CDR2 sequence of SEQ ID NO: 658; and the VH CDR3 sequence of SEQ ID NO: 664, and a human immunoglobulin heavy chain constant domain. In some embodiments, the human immunoglobulin heavy chain constant domain comprises an amino acid sequence selected from the group consisting of 381, 382, 383, and 1807.
• In some embodiments, the activatable antibody comprises a masking moiety (MM) comprising an amino acid sequence selected from the group consisting of SEQ ID NOs: 66, 67, 70, 71, 74, 77, 81, 82, 84, 90, 91, 93, 99; a cleavable moiety (CM) comprising an amino acid sequence selected from the group consisting of SEQ ID NOs: 214, 294, 300, 302, 303, 305, 308, 318, 347, 361, 1092-1102, 1111, and 1157; a combination of a VH CDR1 sequence, a VH CDR2 sequence, a VH CDR3 sequence, a VL CDR1 sequence, a VL CDR2 sequence, and a VL CDR3 sequence, wherein the combination comprises the VL CDR1 sequence of SEQ ID NO: 675 or SEQ ID NO: 676; the VL CDR2 sequence of SEQ ID NO: 678; the VL CDR3 sequence of SEQ ID NO: 683; the VH CDR1 sequence of SEQ ID NO: 653; the VH CDR2 sequence of SEQ ID NO: 658; and the VH CDR3 sequence of SEQ ID NO: 664, a human immunoglobulin heavy chain constant region, and a human immunoglobulin light chain constant domain. In some embodiments, the human immunoglobulin heavy chain constant domain comprises an amino acid sequence selected from the group consisting of SEQ ID NO: 63, 381, 382, 383, and 1807, and the human immunoglobulin light chain constant domain is a human kappa constant domain comprising SEQ ID NO: 61 or SEQ ID NO: 1344.
• n some embodiments, the activatable antibody comprises a masking moiety (MM) comprising an amino acid sequence selected from the group consisting of SEQ ID NOs: 66, 67, 70, 71, 74, 77, 81, 82, 84, 90, 91, 93, 99; a cleavable moiety (CM) comprising an amino acid sequence selected from the group consisting of SEQ ID NOs: 214, 294, 300, 302, 303, 305, 308, 318, 347, 361, 1092-1102, 1111, and 1157; a combination of a VH CDR1 sequence, a VH CDR2 sequence, a VH CDR3 sequence, a VL CDR1 sequence, a VL CDR2 sequence, and a VL CDR3 sequence, wherein the combination comprises the VL CDR1 sequence of SEQ ID NO: 675; the VL CDR2 sequence of SEQ ID NO: 678; the VL CDR3 sequence of SEQ ID NO: 683; the VH CDR1 sequence of SEQ ID NO: 653; the VH CDR2 sequence of SEQ ID NO: 658; and the VH CDR3 sequence of SEQ ID NO: 664.
• In some embodiments, the activatable antibody comprises a masking moiety (MM) comprising an amino acid sequence selected from the group consisting of SEQ ID NOs: 66, 67, 70, 71, 74, 77, 81, 82, 84, 90, 91, 93, 99; a cleavable moiety (CM) comprising an amino acid sequence selected from the group consisting of SEQ ID NOs: 214, 294, 300, 302, 303, 305, 308, 318, 347, 361, 1092-1102, 1111, and 1157; a combination of a VH CDR1 sequence, a VH CDR2 sequence, a VH CDR3 sequence, a VL CDR1 sequence, a VL CDR2 sequence, and a VL CDR3 sequence, wherein the combination comprises the VL CDR1 sequence of SEQ ID NO: 675; the VL CDR2 sequence of SEQ ID NO: 678; the VL CDR3 sequence of SEQ ID NO: 683; the VH CDR1 sequence of SEQ ID NO: 653; the VH CDR2 sequence of SEQ ID NO: 658; and the VH CDR3 sequence of SEQ ID NO: 664, and a human immunoglobulin light chain constant domain. In some embodiments, the human immunoglobulin light chain constant domain is a human kappa constant domain comprising SEQ ID NO: 61 or SEQ ID NO: 1344.
• In some embodiments, the activatable antibody comprises a masking moiety (MM) comprising an amino acid sequence selected from the group consisting of SEQ ID NOs: 66, 67, 70, 71, 74, 77, 81, 82, 84, 90, 91, 93, 99; a cleavable moiety (CM) comprising an amino acid sequence selected from the group consisting of SEQ ID NOs: 214, 294, 300, 302, 303, 305, 308, 318, 347, 361, 1092-1102, 1111, and 1157; a combination of a VH CDR1 sequence, a VH CDR2 sequence, a VH CDR3 sequence, a VL CDR1 sequence, a VL CDR2 sequence, and a VL CDR3 sequence, wherein the combination comprises the VL CDR1 sequence of SEQ ID NO: 675; the VL CDR2 sequence of SEQ ID NO: 678; the VL CDR3 sequence of SEQ ID NO: 683; the VH CDR1 sequence of SEQ ID NO: 653; the VH CDR2 sequence of SEQ ID NO: 658; and the VH CDR3 sequence of SEQ ID NO: 664, and a human immunoglobulin heavy chain constant domain. In some embodiments, the human immunoglobulin heavy chain constant domain comprises an amino acid sequence selected from the group consisting of SEQ ID NO: 63, 381, 382, 383, and 1807.
• In some embodiments, the activatable antibody comprises a masking moiety (MM) comprising an amino acid sequence selected from the group consisting of SEQ ID NOs: 66, 67, 70, 71, 74, 77, 81, 82, 84, 90, 91, 93, 99; a cleavable moiety (CM) comprising an amino acid sequence selected from the group consisting of SEQ ID NOs: 214, 294, 300, 302, 303, 305, 308, 318, 347, 361, 1092-1102, 1111, and 1157; a combination of a VH CDR1 sequence, a VH CDR2 sequence, a VH CDR3 sequence, a VL CDR1 sequence, a VL CDR2 sequence, and a VL CDR3 sequence, wherein the combination comprises the VL CDR1 sequence of SEQ ID NO: 675; the VL CDR2 sequence of SEQ ID NO: 678; the VL CDR3 sequence of SEQ ID NO: 683; the VH CDR1 sequence of SEQ ID NO: 653; the VH CDR2 sequence of SEQ ID NO: 658; and the VH CDR3 sequence of SEQ ID NO: 664, a human immunoglobulin heavy chain constant region, and a human immunoglobulin light chain constant domain. In some embodiments, the human immunoglobulin heavy chain constant domain comprises an amino acid sequence selected from the group consisting of SEQ ID NO: 63, 381, 382, 383, and 1807, and the human immunoglobulin light chain constant domain is a human kappa constant domain comprising SEQ ID NO: 61 or SEQ ID NO: 1344.
• In some embodiments, the activatable antibody comprises a masking moiety (MM) comprising an amino acid sequence selected from the group consisting of SEQ ID NOs: 66, 67, 70, 71, 74, 77, 81, 82, 84, 90, 91, 93, 99; a cleavable moiety (CM) comprising an amino acid sequence selected from the group consisting of SEQ ID NOs: 214, 294, 300, 302, 303, 305, 308, 318, 347, 361, 1092-1102, 1111, and 1157; and a combination of a VH CDR1 sequence, a VH CDR2 sequence, a VH CDR3 sequence, a VL CDR1 sequence, a VL CDR2 sequence, and a VL CDR3 sequence, wherein the combination comprises the VL CDR1 sequence of SEQ ID NO: 676; the VL CDR2 sequence of SEQ ID NO: 678; the VL CDR3 sequence of SEQ ID NO: 683; the VH CDR1 sequence of SEQ ID NO: 653; the VH CDR2 sequence of SEQ ID NO: 658; and the VH CDR3 sequence of SEQ ID NO: 664.
• In some embodiments, the activatable antibody comprises a masking moiety (MM) comprising an amino acid sequence selected from the group consisting of SEQ ID NOs: 66, 67, 70, 71, 74, 77, 81, 82, 84, 90, 91, 93, 99; a cleavable moiety (CM) comprising an amino acid sequence selected from the group consisting of SEQ ID NOs: 214, 294, 300, 302, 303, 305, 308, 318, 347, 361, 1092-1102, 1111, and 1157; a combination of a VH CDR1 sequence, a VH CDR2 sequence, a VH CDR3 sequence, a VL CDR1 sequence, a VL CDR2 sequence, and a VL CDR3 sequence, wherein the combination comprises the VL CDR1 sequence of SEQ ID NO: 676; the VL CDR2 sequence of SEQ ID NO: 678; the VL CDR3 sequence of SEQ ID NO: 683; the VH CDR1 sequence of SEQ ID NO: 653; the VH CDR2 sequence of SEQ ID NO: 658; and the VH CDR3 sequence of SEQ ID NO: 664, and a human immunoglobulin light chain constant domain. In some embodiments, the human immunoglobulin light chain constant domain is a human kappa constant domain comprising SEQ ID NO: 61 or SEQ ID NO: 1344.
• In some embodiments, the activatable antibody comprises a masking moiety (MM) comprising an amino acid sequence selected from the group consisting of SEQ ID NOs: 66, 67, 70, 71, 74, 77, 81, 82, 84, 90, 91, 93, 99; a cleavable moiety (CM) comprising an amino acid sequence selected from the group consisting of SEQ ID NOs: 214, 294, 300, 302, 303, 305, 308, 318, 347, 361, 1092-1102, 1111, and 1157; a combination of a VH CDR1 sequence, a VH CDR2 sequence, a VH CDR3 sequence, a VL CDR1 sequence, a VL CDR2 sequence, and a VL CDR3 sequence, wherein the combination comprises the VL CDR1 sequence of SEQ ID NO: 676; the VL CDR2 sequence of SEQ ID NO: 678; the VL CDR3 sequence of SEQ ID NO: 683; the VH CDR1 sequence of SEQ ID NO: 653; the VH CDR2 sequence of SEQ ID NO: 658; and the VH CDR3 sequence of SEQ ID NO: 664, and a human immunoglobulin heavy chain constant domain. In some embodiments, the human immunoglobulin heavy chain constant domain comprises an amino acid sequence selected from the group consisting of SEQ ID NO: 63, 381, 382, 383, and 1807.
• In some embodiments, the activatable antibody comprises a masking moiety (MM) comprising an amino acid sequence selected from the group consisting of SEQ ID NOs: 66, 67, 70, 71, 74, 77, 81, 82, 84, 90, 91, 93, 99; a cleavable moiety (CM) comprising an amino acid sequence selected from the group consisting of SEQ ID NOs: 214, 294, 300, 302, 303, 305, 308, 318, 347, 361, 1092-1102, 1111, and 1157; a combination of a VH CDR1 sequence, a VH CDR2 sequence, a VH CDR3 sequence, a VL CDR1 sequence, a VL CDR2 sequence, and a VL CDR3 sequence, wherein the combination comprises the VL CDR1 sequence of SEQ ID NO: 676; the VL CDR2 sequence of SEQ ID NO: 678; the VL CDR3 sequence of SEQ ID NO: 683; the VH CDR1 sequence of SEQ ID NO: 653; the VH CDR2 sequence of SEQ ID NO: 658; and the VH CDR3 sequence of SEQ ID NO: 664, a human immunoglobulin heavy chain constant region, and a human immunoglobulin light chain constant domain. In some embodiments, the human immunoglobulin heavy chain constant domain comprises an amino acid sequence selected from the group consisting of SEQ ID NO: 63, 381, 382, 383, and 1807, and the human immunoglobulin light chain constant domain is a human kappa constant domain comprising SEQ ID NO: 61 or SEQ ID NO: 1344.
• In some embodiments, the activatable antibody comprises a MM comprising an amino acid sequence selected from the group consisting of SEQ ID NOs: 66, 67, 70, 71, 74, 77, 81, 82, 84, 90, 91, 93, 99; a CM comprising an amino acid sequence selected from the group consisting of SEQ ID NOs: 214, 294, 300, 302, 303, 305, 308, 318, 347, 361, 1092-1102, 1111, and 1157; and a combination of a VH CDR1 sequence, a VH CDR2 sequence, a VH CDR3 sequence, a VL CDR1 sequence, a VL CDR2 sequence, and a VL CDR3 sequence, wherein the combination comprises the VH CDR sequences of the variable heavy chain sequence of SEQ ID NO: 21 and the VL CDR sequences of the variable light chain sequence of SEQ ID NO: 47. In some embodiments, the combination further comprises a human immunoglobulin heavy chain constant region, a human immunoglobulin light chain constant domain, or both a human immunoglobulin heavy chain constant region and a human immunoglobulin light chain constant domain. In some embodiments, the human immunoglobulin heavy chain constant domain comprises an amino acid sequence selected from the group consisting of SEQ ID NO: 63, 381, 382, 383, and 1807. In some embodiments, the human immunoglobulin light chain constant domain is a human kappa constant domain comprising SEQ ID NO: 61 or SEQ ID NO: 1344.
• In some embodiments, the activatable antibody comprises a MM comprising an amino acid sequence selected from the group consisting of SEQ ID NOs: 66, 67, 70, 71, 74, 77, 81, 82, 84, 90, 91, 93, 99; a CM comprising an amino acid sequence selected from the group consisting of SEQ ID NOs: 214, 294, 300, 302, 303, 305, 308, 318, 347, 361, 1092-1102, 1111, and 1157; and a combination of a VH CDR1 sequence, a VH CDR2 sequence, a VH CDR3 sequence, a VL CDR1 sequence, a VL CDR2 sequence, and a VL CDR3 sequence, wherein the combination comprises the VL CDR1 sequence of SEQ ID NO: 676; the VL CDR2 sequence of SEQ ID NO: 678; the VL CDR3 sequence of SEQ ID NO: 683; the VH CDR1 sequence of SEQ ID NO: 653; the VH CDR2 sequence of SEQ ID NO: 658; and the VH CDR3 sequence of SEQ ID NO: 664. In some embodiments, the combination further comprises a human immunoglobulin heavy chain constant region, a human immunoglobulin light chain constant domain, or both a human immunoglobulin heavy chain constant region and a human immunoglobulin light chain constant domain. In some embodiments, the human immunoglobulin heavy chain constant domain comprises an amino acid sequence selected from the group consisting of SEQ ID NO: 63, 381, 382, 383, and 1807. In some embodiments, the human immunoglobulin light chain constant domain is a human kappa constant domain comprising SEQ ID NO: 61 or SEQ ID NO: 1344.
• In some embodiments, the activatable antibody comprises a MM comprising an amino acid sequence selected from the group consisting of SEQ ID NOs: 66, 67, 70, 71, 74, 77, 81, 82, 84, 90, 91, 93, 99; a cleavable moiety (CM) comprising an amino acid sequence selected from the group consisting of SEQ ID NOs: 214, 294, 300, 302, 303, 305, 308, 318, 347, 361, 1092-1102, 1111, and 1157; and a combination of a variable heavy chain (VH) sequence of SEQ ID NO: 21 and a variable light chain (VL) sequence of SEQ ID NO: 47. In some embodiments, the combination further comprises a human immunoglobulin heavy chain constant region, a human immunoglobulin light chain constant domain, or both a human immunoglobulin heavy chain constant region and a human immunoglobulin light chain constant domain. In some embodiments, the human immunoglobulin heavy chain constant domain comprises an amino acid sequence selected from the group consisting of SEQ ID NO: 63, 381, 382, 383, and 1807. In some embodiments, the human immunoglobulin light chain constant domain is a human kappa constant domain comprising SEQ ID NO: 61 or SEQ ID NO: 1344.
• In some embodiments, the activatable antibody comprises a masking moiety (MM) comprising the amino acid sequence TSYCSIEHYPCNTHH (SEQ ID NO: 99), which is referred to herein as mask PD034 or PD34, a cleavable moiety (CM) comprising the amino acid sequence ISSGLLSGRSDNP (SEQ ID NO: 1100), which is also referred to herein as substrate 2011, and a combination of a VH CDR1 sequence, a VH CDR2 sequence, a VH CDR3 sequence, a VL CDR1 sequence, a VL CDR2 sequence, and a VL CDR3 sequence, wherein the combination comprises the VH CDR sequences of the variable heavy chain sequence of SEQ ID NO: 21 and the VL CDR sequences of the variable light chain sequence of SEQ ID NO: 47. In some embodiments, the combination further comprises a human immunoglobulin heavy chain constant region, a human immunoglobulin light chain constant domain, or both a human immunoglobulin heavy chain constant region and a human immunoglobulin light chain constant domain. In some embodiments, the human immunoglobulin heavy chain constant domain comprises an amino acid sequence selected from the group consisting of SEQ ID NO: 63, 381, 382, 383, and 1807. In some embodiments, the human immunoglobulin light chain constant domain is a human kappa constant domain comprising SEQ ID NO: 61 or SEQ ID NO: 1344.
• In some embodiments, the activatable antibody comprises a masking moiety (MM) comprising the amino acid sequence TSYCSIEHYPCNTHH (SEQ ID NO: 99), a cleavable moiety (CM) comprising the amino acid sequence ISSGLLSGRSDNP (SEQ ID NO: 1100), and a combination of a VH CDR1 sequence, a VH CDR2 sequence, a VH CDR3 sequence, a VL CDR1 sequence, a VL CDR2 sequence, and a VL CDR3 sequence, wherein the combination comprises the VL CDR1 sequence of SEQ ID NO: 676; the VL CDR2 sequence of SEQ ID NO: 678; the VL CDR3 sequence of SEQ ID NO: 683; the VH CDR1 sequence of SEQ ID NO: 653; the VH CDR2 sequence of SEQ ID NO: 658; and the VH CDR3 sequence of SEQ ID NO: 664. In some embodiments, the combination further comprises a human immunoglobulin heavy chain constant region, a human immunoglobulin light chain constant domain, or both a human immunoglobulin heavy chain constant region and a human immunoglobulin light chain constant domain. In some embodiments, the human immunoglobulin heavy chain constant domain comprises an amino acid sequence selected from the group consisting of SEQ ID NO: 63, 381, 382, 383, and 1807. In some embodiments, the human immunoglobulin light chain constant domain is a human kappa constant domain comprising SEQ ID NO: 61 or SEQ ID NO: 1344.
• In some embodiments, the activatable antibody comprises a masking moiety (MM) comprising the amino acid sequence TSYCSIEHYPCNTHH (SEQ ID NO: 99), a cleavable moiety (CM) comprising the amino acid sequence ISSGLLSGRSDNP (SEQ ID NO: 1100), and a combination of a variable heavy chain (VH) sequence of SEQ ID NO: 21 and a variable light chain (VL) sequence of SEQ ID NO: 47. In some embodiments, the combination further comprises a human immunoglobulin heavy chain constant region, a human immunoglobulin light chain constant domain, or both a human immunoglobulin heavy chain constant region and a human immunoglobulin light chain constant domain. In some embodiments, the human immunoglobulin heavy chain constant domain comprises an amino acid sequence selected from the group consisting of SEQ ID NO: 63, 381, 382, 383, and 1807. In some embodiments, the human immunoglobulin light chain constant domain is a human kappa constant domain comprising SEQ ID NO: 61 or SEQ ID NO: 1344.
• In some embodiments, the activatable antibody comprises a masking moiety (MM) comprising the amino acid sequence TSYCSIEHYPCNTHH (SEQ ID NO: 99), which is referred to herein as mask PD034 or PD34, a cleavable moiety (CM) comprising the amino acid sequence ISSGLLSGRSANP (SEQ ID NO: 1101), which is also referred to herein as substrate 2012, and a combination of a VH CDR1 sequence, a VH CDR2 sequence, a VH CDR3 sequence, a VL CDR1 sequence, a VL CDR2 sequence, and a VL CDR3 sequence, wherein the combination comprises the VH CDR sequences of the variable heavy chain sequence of SEQ ID NO: 21 and the VL CDR sequences of the variable light chain sequence of SEQ ID NO: 47. In some embodiments, the combination further comprises a human immunoglobulin heavy chain constant region, a human immunoglobulin light chain constant domain, or both a human immunoglobulin heavy chain constant region and a human immunoglobulin light chain constant domain. In some embodiments, the human immunoglobulin heavy chain constant domain comprises an amino acid sequence selected from the group consisting of SEQ ID NO: 63, 381, 382, 383, and 1807. In some embodiments, the human immunoglobulin light chain constant domain is a human kappa constant domain comprising SEQ ID NO: 61 or SEQ ID NO: 1344.
• In some embodiments, the activatable antibody comprises a masking moiety (MM) comprising the amino acid sequence TSYCSIEHYPCNTHH (SEQ ID NO: 99), a cleavable moiety (CM) comprising the amino acid sequence ISSGLLSGRSANP (SEQ ID NO: 1101), and a combination of a VH CDR1 sequence, a VH CDR2 sequence, a VH CDR3 sequence, a VL CDR1 sequence, a VL CDR2 sequence, and a VL CDR3 sequence, wherein the combination comprises the VL CDR1 sequence of SEQ ID NO: 676; the VL CDR2 sequence of SEQ ID NO: 678; the VL CDR3 sequence of SEQ ID NO: 683; the VH CDR1 sequence of SEQ ID NO: 653; the VH CDR2 sequence of SEQ ID NO: 658; and the VH CDR3 sequence of SEQ ID NO: 664. In some embodiments, the combination further comprises a human immunoglobulin heavy chain constant region, a human immunoglobulin light chain constant domain, or both a human immunoglobulin heavy chain constant region and a human immunoglobulin light chain constant domain. In some embodiments, the human immunoglobulin heavy chain constant domain comprises an amino acid sequence selected from the group consisting of SEQ ID NO: 63, 381, 382, 383, and 1807. In some embodiments, the human immunoglobulin light chain constant domain is a human kappa constant domain comprising SEQ ID NO: 61 or SEQ ID NO: 1344.
• In some embodiments, the activatable antibody comprises a masking moiety (MM) comprising the amino acid sequence TSYCSIEHYPCNTHH (SEQ ID NO: 99), a cleavable moiety (CM) comprising the amino acid sequence ISSGLLSGRSANP (SEQ ID NO: 1101), and a combination of a variable heavy chain (VH) sequence of SEQ ID NO: 21 and a variable light chain (VL) sequence of SEQ ID NO: 47. In some embodiments, the combination further comprises a human immunoglobulin heavy chain constant region, a human immunoglobulin light chain constant domain, or both a human immunoglobulin heavy chain constant region and a human immunoglobulin light chain constant domain. In some embodiments, the human immunoglobulin heavy chain constant domain comprises an amino acid sequence selected from the group consisting of SEQ ID NO: 63, 381, 382, 383, and 1807. In some embodiments, the human immunoglobulin light chain constant domain is a human kappa constant domain comprising SEQ ID NO: 61 or SEQ ID NO: 1344.
• In some embodiments, the activatable antibody comprises a masking moiety (MM) comprising the amino acid sequence TSYCSIEHYPCNTHH (SEQ ID NO: 99), which is referred to herein as mask PD034 or PD34, a cleavable moiety (CM) comprising the amino acid sequence ISSGLLSGRSDNP (SEQ ID NO: 1100), which is also referred to herein as substrate 2011, and a combination of a VH CDR1 sequence, a VH CDR2 sequence, a VH CDR3 sequence, a VL CDR1 sequence, a VL CDR2 sequence, and a VL CDR3 sequence, wherein the combination comprises the VH CDR sequences of the variable heavy chain sequence of SEQ ID NO: 21 and the VL CDR sequences of the variable light chain sequence of SEQ ID NO: 47. In some embodiments, the combination further comprises a human immunoglobulin heavy chain constant region, or both a human immunoglobulin heavy chain constant region and a human immunoglobulin light chain constant domain. In some embodiments, the human immunoglobulin heavy chain constant domain comprises an amino acid sequence selected from the group consisting of SEQ ID NO: 63, 381, 382, 383, and 1807. In some embodiments, the human immunoglobulin light chain constant domain is a human kappa constant domain comprising SEQ ID NO: 61 or SEQ ID NO: 1344.
• In some embodiments, the activatable antibody comprises a masking moiety (MM) comprising the amino acid sequence TSYCSIEHYPCNTHH (SEQ ID NO: 99), a cleavable moiety (CM) comprising the amino acid sequence ISSGLLSGRSDNP (SEQ ID NO: 1100), and a combination of a VH CDR1 sequence, a VH CDR2 sequence, a VH CDR3 sequence, a VL CDR1 sequence, a VL CDR2 sequence, and a VL CDR3 sequence, wherein the combination comprises the VL CDR1 sequence of SEQ ID NO: 676; the VL CDR2 sequence of SEQ ID NO: 678; the VL CDR3 sequence of SEQ ID NO: 683; the VH CDR1 sequence of SEQ ID NO: 653; the VH CDR2 sequence of SEQ ID NO: 658; and the VH CDR3 sequence of SEQ ID NO: 664. In some embodiments, the combination further comprises a human immunoglobulin heavy chain constant region, a human immunoglobulin light chain constant domain, or both a human immunoglobulin heavy chain constant region and a human immunoglobulin light chain constant domain. In some embodiments, the human immunoglobulin heavy chain constant domain comprises an amino acid sequence selected from the group consisting of SEQ ID NO: 63, 381, 382, 383, and 1807. In some embodiments, the human immunoglobulin light chain constant domain is a human kappa constant domain comprising SEQ ID NO: 61 or SEQ ID NO: 1344.
• In some embodiments, the activatable antibody comprises a masking moiety (MM) comprising the amino acid sequence TSYCSIEHYPCNTHH (SEQ ID NO: 99), a cleavable moiety (CM) comprising the amino acid sequence ISSGLLSGRSDNP (SEQ ID NO: 1100), and a combination of a variable heavy chain (VH) sequence of SEQ ID NO: 21 and a variable light chain (VL) sequence of SEQ ID NO: 47. In some embodiments, the combination further comprises a human immunoglobulin heavy chain constant region, a human immunoglobulin light chain constant domain, or both a human immunoglobulin heavy chain constant region and a human immunoglobulin light chain constant domain. In some embodiments, the human immunoglobulin heavy chain constant domain comprises an amino acid sequence selected from the group consisting of SEQ ID NO: 63, 381, 382, 383, and 1807. In some embodiments, the human immunoglobulin light chain constant domain is a human kappa constant domain comprising SEQ ID NO: 61 or SEQ ID NO: 1344.
• In some embodiments, the activatable antibody comprises a masking moiety (MM) comprising the amino acid sequence TSYCSIEHYPCNTHH (SEQ ID NO: 99), which is referred to herein as mask PD034 or PD34, a cleavable moiety (CM) comprising the amino acid sequence ISSGLLSGRSDNH (SEQ ID NO: 214), which is also referred to herein as substrate 2001, and a combination of a VH CDR1 sequence, a VH CDR2 sequence, a VH CDR3 sequence, a VL CDR1 sequence, a VL CDR2 sequence, and a VL CDR3 sequence, wherein the combination comprises the VH CDR sequences of the variable heavy chain sequence of SEQ ID NO: 21 and the VL CDR sequences of the variable light chain sequence of SEQ ID NO: 47. In some embodiments, the combination further comprises a human immunoglobulin heavy chain constant region, a human immunoglobulin light chain constant domain, or both a human immunoglobulin heavy chain constant region and a human immunoglobulin light chain constant domain. In some embodiments, the human immunoglobulin heavy chain constant domain comprises an amino acid sequence selected from the group consisting of SEQ ID NO: 63, 381, 382, 383, and 1807. In some embodiments, the human immunoglobulin light chain constant domain is a human kappa constant domain comprising SEQ ID NO: 61 or SEQ ID NO: 1344.
• In some embodiments, the activatable antibody comprises a masking moiety (MM) comprising the amino acid sequence TSYCSIEHYPCNTHH (SEQ ID NO: 99), a cleavable moiety (CM) comprising the amino acid sequence ISSGLLSGRSDNH (SEQ ID NO: 214), and a combination of a VH CDR1 sequence, a VH CDR2 sequence, a VH CDR3 sequence, a VL CDR1 sequence, a VL CDR2 sequence, and a VL CDR3 sequence, wherein the combination comprises the VL CDR1 sequence of SEQ ID NO: 676; the VL CDR2 sequence of SEQ ID NO: 678; the VL CDR3 sequence of SEQ ID NO: 683; the VH CDR1 sequence of SEQ ID NO: 653; the VH CDR2 sequence of SEQ ID NO: 658; and the VH CDR3 sequence of SEQ ID NO: 664. In some embodiments, the combination further comprises a human immunoglobulin heavy chain constant region, a human immunoglobulin light chain constant domain, or both a human immunoglobulin heavy chain constant region and a human immunoglobulin light chain constant domain. In some embodiments, the human immunoglobulin heavy chain constant domain comprises an amino acid sequence selected from the group consisting of SEQ ID NO: 63, 381, 382, 383, and 1807. In some embodiments, the human immunoglobulin light chain constant domain is a human kappa constant domain comprising SEQ ID NO: 61 or SEQ ID NO: 1344.
• In some embodiments, the activatable antibody comprises a masking moiety (MM) comprising the amino acid sequence TSYCSIEHYPCNTHH (SEQ ID NO: 99), a cleavable moiety (CM) comprising the amino acid sequence ISSGLLSGRSDNH (SEQ ID NO: 214), and a combination of a variable heavy chain (VH) sequence of SEQ ID NO: 21 and a variable light chain (VL) sequence of SEQ ID NO: 47. In some embodiments, the combination further comprises a human immunoglobulin heavy chain constant region, a human immunoglobulin light chain constant domain, or both a human immunoglobulin heavy chain constant region and a human immunoglobulin light chain constant domain. In some embodiments, the human immunoglobulin heavy chain constant domain comprises an amino acid sequence selected from the group consisting of SEQ ID NO: 63, 381, 382, 383, and 1807. In some embodiments, the human immunoglobulin light chain constant domain is a human kappa constant domain comprising SEQ ID NO: 61 or SEQ ID NO: 1344.
• In some embodiments, the activatable antibody comprises a masking moiety (MM) comprising the amino acid sequence TSYCSIEHYPCNTHH (SEQ ID NO: 99), a cleavable moiety (CM) comprising the amino acid sequence ISSGLLSGRSGNH (SEQ ID NO: 361), which is also referred to herein as substrate 2002, and a combination selected from the group consisting of (a) a combination of a VH CDR1 sequence, a VH CDR2 sequence, a VH CDR3 sequence, a VL CDR1 sequence, a VL CDR2 sequence, and a VL CDR3 sequence, wherein the combination comprises the VH CDR sequences of the variable heavy chain sequence of SEQ ID NO: 21 and the VL CDR sequences of the variable light chain sequence of SEQ ID NO: 47; (b) a combination of a VH CDR1 sequence, a VH CDR2 sequence, a VH CDR3 sequence, a VL CDR1 sequence, a VL CDR2 sequence, and a VL CDR3 sequence, wherein the combination comprises the VL CDR1 sequence of SEQ ID NO: 676; the VL CDR2 sequence of SEQ ID NO: 678; the VL CDR3 sequence of SEQ ID NO: 683; the VH CDR1 sequence of SEQ ID NO: 653; the VH CDR2 sequence of SEQ ID NO: 658; and the VH CDR3 sequence of SEQ ID NO: 664; and (c) a combination of a variable heavy chain (VH) sequence of SEQ ID NO: 21 and a variable light chain (VL) sequence of SEQ ID NO: 47. In some embodiments, the combination further comprises a human immunoglobulin heavy chain constant region, a human immunoglobulin light chain constant domain, or both a human immunoglobulin heavy chain constant region and a human immunoglobulin light chain constant domain. In some embodiments, the human immunoglobulin heavy chain constant domain comprises an amino acid sequence selected from the group consisting of SEQ ID NO: 63, 381, 382, 383, and 1807. In some embodiments, the human immunoglobulin light chain constant domain is a human kappa constant domain comprising SEQ ID NO: 61 or SEQ ID NO: 1344.
• In some embodiments, the activatable antibody comprises a masking moiety (MM) comprising the amino acid sequence TSYCSIEHYPCNTHH (SEQ ID NO: 99), a cleavable moiety (CM) comprising the amino acid sequence ISSGLLSGRSANPRG (SEQ ID NO: 1092), which is also referred to herein as substrate 2003, and a combination selected from the group consisting of (a) a combination of a VH CDR1 sequence, a VH CDR2 sequence, a VH CDR3 sequence, a VL CDR1 sequence, a VL CDR2 sequence, and a VL CDR3 sequence, wherein the combination comprises the VH CDR sequences of the variable heavy chain sequence of SEQ ID NO: 21 and the VL CDR sequences of the variable light chain sequence of SEQ ID NO: 47; (b) a combination of a VH CDR1 sequence, a VH CDR2 sequence, a VH CDR3 sequence, a VL CDR1 sequence, a VL CDR2 sequence, and a VL CDR3 sequence, wherein the combination comprises the VL CDR1 sequence of SEQ ID NO: 676; the VL CDR2 sequence of SEQ ID NO: 678; the VL CDR3 sequence of SEQ ID NO: 683; the VH CDR1 sequence of SEQ ID NO: 653; the VH CDR2 sequence of SEQ ID NO: 658; and the VH CDR3 sequence of SEQ ID NO: 664; and (c) a combination of a variable heavy chain (VH) sequence of SEQ ID NO: 21 and a variable light chain (VL) sequence of SEQ ID NO: 47. In some embodiments, the combination further comprises a human immunoglobulin heavy chain constant region, a human immunoglobulin light chain constant domain, or both a human immunoglobulin heavy chain constant region and a human immunoglobulin light chain constant domain. In some embodiments, the human immunoglobulin heavy chain constant domain comprises an amino acid sequence selected from the group consisting of SEQ ID NO: 63, 381, 382, 383, and 1807. In some embodiments, the human immunoglobulin light chain constant domain is a human kappa constant domain comprising SEQ ID NO: 61 or SEQ ID NO: 1344.
• In some embodiments, the activatable antibody comprises a masking moiety (MM) comprising the amino acid sequence TSYCSIEHYPCNTHH (SEQ ID NO: 99), a cleavable moiety (CM) comprising the amino acid sequence ISSGLLSGRSDDH (SEQ ID NO: 1095), which is also referred to herein as substrate 2006, and a combination selected from the group consisting of (a) a combination of a VH CDR1 sequence, a VH CDR2 sequence, a VH CDR3 sequence, a VL CDR1 sequence, a VL CDR2 sequence, and a VL CDR3 sequence, wherein the combination comprises the VH CDR sequences of the variable heavy chain sequence of SEQ ID NO: 21 and the VL CDR sequences of the variable light chain sequence of SEQ ID NO: 47; (b) a combination of a VH CDR1 sequence, a VH CDR2 sequence, a VH CDR3 sequence, a VL CDR1 sequence, a VL CDR2 sequence, and a VL CDR3 sequence, wherein the combination comprises the VL CDR1 sequence of SEQ ID NO: 676; the VL CDR2 sequence of SEQ ID NO: 678; the VL CDR3 sequence of SEQ ID NO: 683; the VH CDR1 sequence of SEQ ID NO: 653; the VH CDR2 sequence of SEQ ID NO: 658; and the VH CDR3 sequence of SEQ ID NO: 664; and (c) a combination of a variable heavy chain (VH) sequence of SEQ ID NO: 21 and a variable light chain (VL) sequence of SEQ ID NO: 47. In some embodiments, the combination further comprises a human immunoglobulin heavy chain constant region, a human immunoglobulin light chain constant domain, or both a human immunoglobulin heavy chain constant region and a human immunoglobulin light chain constant domain. In some embodiments, the human immunoglobulin heavy chain constant domain comprises an amino acid sequence selected from the group consisting of SEQ ID NO: 63, 381, 382, 383, and 1807. In some embodiments, the human immunoglobulin light chain constant domain is a human kappa constant domain comprising SEQ ID NO: 61 or SEQ ID NO: 1344.
• In some embodiments, the activatable antibody comprises a masking moiety (MM) comprising the amino acid sequence TSYCSIEHYPCNTHH (SEQ ID NO: 99), a cleavable moiety (CM) comprising the amino acid sequence ISSGLLSGRSDIH (SEQ ID NO: 1096), which is also referred to herein as substrate 2007, and a combination selected from the group consisting of (a) a combination of a VH CDR1 sequence, a VH CDR2 sequence, a VH CDR3 sequence, a VL CDR1 sequence, a VL CDR2 sequence, and a VL CDR3 sequence, wherein the combination comprises the VH CDR sequences of the variable heavy chain sequence of SEQ ID NO: 21 and the VL CDR sequences of the variable light chain sequence of SEQ ID NO: 47; (b) a combination of a VH CDR1 sequence, a VH CDR2 sequence, a VH CDR3 sequence, a VL CDR1 sequence, a VL CDR2 sequence, and a VL CDR3 sequence, wherein the combination comprises the VL CDR1 sequence of SEQ ID NO: 676; the VL CDR2 sequence of SEQ ID NO: 678; the VL CDR3 sequence of SEQ ID NO: 683; the VH CDR1 sequence of SEQ ID NO: 653; the VH CDR2 sequence of SEQ ID NO: 658; and the VH CDR3 sequence of SEQ ID NO: 664; and (c) a combination of a variable heavy chain (VH) sequence of SEQ ID NO: 21 and a variable light chain (VL) sequence of SEQ ID NO: 47. In some embodiments, the combination further comprises a human immunoglobulin heavy chain constant region, a human immunoglobulin light chain constant domain, or both a human immunoglobulin heavy chain constant region and a human immunoglobulin light chain constant domain. In some embodiments, the human immunoglobulin heavy chain constant domain comprises an amino acid sequence selected from the group consisting of SEQ ID NO: 63, 381, 382, 383, and 1807. In some embodiments, the human immunoglobulin light chain constant domain is a human kappa constant domain comprising SEQ ID NO: 61 or SEQ ID NO: 1344.
• In some embodiments, the activatable antibody comprises a masking moiety (MM) comprising the amino acid sequence TSYCSIEHYPCNTHH (SEQ ID NO: 99), a cleavable moiety (CM) comprising the amino acid sequence ISSGLLSGRSDQH (SEQ ID NO: 1097), which is also referred to herein as 2008, and a combination selected from the group consisting of (a) a combination of a VH CDR1 sequence, a VH CDR2 sequence, a VH CDR3 sequence, a VL CDR1 sequence, a VL CDR2 sequence, and a VL CDR3 sequence, wherein the combination comprises the VH CDR sequences of the variable heavy chain sequence of SEQ ID NO: 21 and the VL CDR sequences of the variable light chain sequence of SEQ ID NO: 47; (b) a combination of a VH CDR1 sequence, a VH CDR2 sequence, a VH CDR3 sequence, a VL CDR1 sequence, a VL CDR2 sequence, and a VL CDR3 sequence, wherein the combination comprises the VL CDR1 sequence of SEQ ID NO: 676; the VL CDR2 sequence of SEQ ID NO: 678; the VL CDR3 sequence of SEQ ID NO: 683; the VH CDR1 sequence of SEQ ID NO: 653; the VH CDR2 sequence of SEQ ID NO: 658; and the VH CDR3 sequence of SEQ ID NO: 664; and (c) a combination of a variable heavy chain (VH) sequence of SEQ ID NO: 21 and a variable light chain (VL) sequence of SEQ ID NO: 47. In some embodiments, the combination further comprises a human immunoglobulin heavy chain constant region, a human immunoglobulin light chain constant domain, or both a human immunoglobulin heavy chain constant region and a human immunoglobulin light chain constant domain. In some embodiments, the human immunoglobulin heavy chain constant domain comprises an amino acid sequence selected from the group consisting of SEQ ID NO: 63, 381, 382, 383, and 1807. In some embodiments, the human immunoglobulin light chain constant domain is a human kappa constant domain comprising SEQ ID NO: 61 or SEQ ID NO: 1344.
• In some embodiments, the activatable antibody comprises a masking moiety (MM) comprising the amino acid sequence TSYCSIEHYPCNTHH (SEQ ID NO: 99), a cleavable moiety (CM) comprising the amino acid sequence ISSGLLSGRSDTH (SEQ ID NO: 1098), which is also referred to herein as substrate 2009, and a combination selected from the group consisting of (a) a combination of a VH CDR1 sequence, a VH CDR2 sequence, a VH CDR3 sequence, a VL CDR1 sequence, a VL CDR2 sequence, and a VL CDR3 sequence, wherein the combination comprises the VH CDR sequences of the variable heavy chain sequence of SEQ ID NO: 21 and the VL CDR sequences of the variable light chain sequence of SEQ ID NO: 47; (b) a combination of a VH CDR1 sequence, a VH CDR2 sequence, a VH CDR3 sequence, a VL CDR1 sequence, a VL CDR2 sequence, and a VL CDR3 sequence, wherein the combination comprises the VL CDR1 sequence of SEQ ID NO: 676; the VL CDR2 sequence of SEQ ID NO: 678; the VL CDR3 sequence of SEQ ID NO: 683; the VH CDR1 sequence of SEQ ID NO: 653; the VH CDR2 sequence of SEQ ID NO: 658; and the VH CDR3 sequence of SEQ ID NO: 664; and (c) a combination of a variable heavy chain (VH) sequence of SEQ ID NO: 21 and a variable light chain (VL) sequence of SEQ ID NO: 47. In some embodiments, the combination further comprises a human immunoglobulin heavy chain constant region, a human immunoglobulin light chain constant domain, or both a human immunoglobulin heavy chain constant region and a human immunoglobulin light chain constant domain. In some embodiments, the human immunoglobulin heavy chain constant domain comprises an amino acid sequence selected from the group consisting of SEQ ID NO: 63, 381, 382, 383, and 1807. In some embodiments, the human immunoglobulin light chain constant domain is a human kappa constant domain comprising SEQ ID NO: 61 or SEQ ID NO: 1344.
• In some embodiments, the activatable antibody comprises a masking moiety (MM) comprising the amino acid sequence TSYCSIEHYPCNTHH (SEQ ID NO: 99), a cleavable moiety (CM) comprising the amino acid sequence ISSGLLSGRSDYH (SEQ ID NO: 1099), which is also referred to herein as 2010, and a combination selected from the group consisting of (a) a combination of a VH CDR1 sequence, a VH CDR2 sequence, a VH CDR3 sequence, a VL CDR1 sequence, a VL CDR2 sequence, and a VL CDR3 sequence, wherein the combination comprises the VH CDR sequences of the variable heavy chain sequence of SEQ ID NO: 21 and the VL CDR sequences of the variable light chain sequence of SEQ ID NO: 47; (b) a combination of a VH CDR1 sequence, a VH CDR2 sequence, a VH CDR3 sequence, a VL CDR1 sequence, a VL CDR2 sequence, and a VL CDR3 sequence, wherein the combination comprises the VL CDR1 sequence of SEQ ID NO: 676; the VL CDR2 sequence of SEQ ID NO: 678; the VL CDR3 sequence of SEQ ID NO: 683; the VH CDR1 sequence of SEQ ID NO: 653; the VH CDR2 sequence of SEQ ID NO: 658; and the VH CDR3 sequence of SEQ ID NO: 664; and (c) a combination of a variable heavy chain (VH) sequence of SEQ ID NO: 21 and a variable light chain (VL) sequence of SEQ ID NO: 47. In some embodiments, the combination further comprises a human immunoglobulin heavy chain constant region, a human immunoglobulin light chain constant domain, or both a human immunoglobulin heavy chain constant region and a human immunoglobulin light chain constant domain. In some embodiments, the human immunoglobulin heavy chain constant domain comprises an amino acid sequence selected from the group consisting of SEQ ID NO: 63, 381, 382, 383, and 1807. In some embodiments, the human immunoglobulin light chain constant domain is a human kappa constant domain comprising SEQ ID NO: 61 or SEQ ID NO: 1344.
• In some embodiments, the activatable antibody comprises a masking moiety (MM) comprising the amino acid sequence TSYCSIEHYPCNTHH (SEQ ID NO: 99), a cleavable moiety (CM) comprising the amino acid sequence ISSGLLSGRSANI (SEQ ID NO: 1102), which is also referred to herein as substrate 2013, and a combination selected from the group consisting of (a) a combination of a VH CDR1 sequence, a VH CDR2 sequence, a VH CDR3 sequence, a VL CDR1 sequence, a VL CDR2 sequence, and a VL CDR3 sequence, wherein the combination comprises the VH CDR sequences of the variable heavy chain sequence of SEQ ID NO: 21 and the VL CDR sequences of the variable light chain sequence of SEQ ID NO: 47; (b) a combination of a VH CDR1 sequence, a VH CDR2 sequence, a VH CDR3 sequence, a VL CDR1 sequence, a VL CDR2 sequence, and a VL CDR3 sequence, wherein the combination comprises the VL CDR1 sequence of SEQ ID NO: 676; the VL CDR2 sequence of SEQ ID NO: 678; the VL CDR3 sequence of SEQ ID NO: 683; the VH CDR1 sequence of SEQ ID NO: 653; the VH CDR2 sequence of SEQ ID NO: 658; and the VH CDR3 sequence of SEQ ID NO: 664; and (c) a combination of a variable heavy chain (VH) sequence of SEQ ID NO: 21 and a variable light chain (VL) sequence of SEQ ID NO: 47. In some embodiments, the combination further comprises a human immunoglobulin heavy chain constant region, a human immunoglobulin light chain constant domain, or both a human immunoglobulin heavy chain constant region and a human immunoglobulin light chain constant domain. In some embodiments, the human immunoglobulin heavy chain constant domain comprises an amino acid sequence selected from the group consisting of SEQ ID NO: 63, 381, 382, 383, and 1807. In some embodiments, the human immunoglobulin light chain constant domain is a human kappa constant domain comprising SEQ ID NO: 61 or SEQ ID NO: 1344.
• In some embodiments, the activatable antibody comprises a masking moiety (MM) comprising the amino acid sequence TSYCSIEHYPCNTHH (SEQ ID NO: 99), a cleavable moiety (CM) comprising the amino acid sequence ISSGLLSGRSDNI (SEQ ID NO: 1111), which is also referred to herein as substrate 2014, and a combination selected from the group consisting of (a) a combination of a VH CDR1 sequence, a VH CDR2 sequence, a VH CDR3 sequence, a VL CDR1 sequence, a VL CDR2 sequence, and a VL CDR3 sequence, wherein the combination comprises the VH CDR sequences of the variable heavy chain sequence of SEQ ID NO: 21 and the VL CDR sequences of the variable light chain sequence of SEQ ID NO: 47; (b) a combination of a VH CDR1 sequence, a VH CDR2 sequence, a VH CDR3 sequence, a VL CDR1 sequence, a VL CDR2 sequence, and a VL CDR3 sequence, wherein the combination comprises the VL CDR1 sequence of SEQ ID NO: 676; the VL CDR2 sequence of SEQ ID NO: 678; the VL CDR3 sequence of SEQ ID NO: 683; the VH CDR1 sequence of SEQ ID NO: 653; the VH CDR2 sequence of SEQ ID NO: 658; and the VH CDR3 sequence of SEQ ID NO: 664; and (c) a combination of a variable heavy chain (VH) sequence of SEQ ID NO: 21 and a variable light chain (VL) sequence of SEQ ID NO: 47. In some embodiments, the combination further comprises a human immunoglobulin heavy chain constant region, a human immunoglobulin light chain constant domain, or both a human immunoglobulin heavy chain constant region and a human immunoglobulin light chain constant domain. In some embodiments, the human immunoglobulin heavy chain constant domain comprises an amino acid sequence selected from the group consisting of SEQ ID NO: 63, 381, 382, 383, and 1807. In some embodiments, the human immunoglobulin light chain constant domain is a human kappa constant domain comprising SEQ ID NO: 61 or SEQ ID NO: 1344.
• In some embodiments, the activatable antibody comprises a light chain comprising the amino acid sequence of SEQ ID NO: 1151; and a heavy chain comprising the amino acid sequence of SEQ ID NO:21.
• In some embodiments, the activatable antibody comprises a light chain comprising the amino acid sequence of SEQ ID NO: 1152; and a heavy chain comprising the amino acid sequence of SEQ ID NO:21.
• In some embodiments, the activatable antibody comprises a light chain comprising the amino acid sequence of SEQ ID NO: 1190; and a heavy chain comprising the amino acid sequence of SEQ ID NO:21.
• In some embodiments, the activatable antibody comprises a light chain comprising the amino acid sequence of SEQ ID NO: 1191; and a heavy chain comprising the amino acid sequence of SEQ ID NO:21.
• In some embodiments, the activatable antibody comprises a light chain comprising the amino acid sequence of SEQ ID NO: 1198; and a heavy chain comprising the amino acid sequence of SEQ ID NO:21.
• In some embodiments, the activatable antibody comprises a light chain comprising the amino acid sequence of SEQ ID NO: 1199; and a heavy chain comprising the amino acid sequence of SEQ ID NO:21.
• In some embodiments, the activatable antibody comprises a light chain comprising the amino acid sequence of SEQ ID NO: 2055; and a heavy chain comprising the amino acid sequence of SEQ ID NO: 2052.
• In some embodiments, the activatable antibody comprises a light chain comprising the amino acid sequence of SEQ ID NO: 2054; and a heavy chain comprising the amino acid sequence of SEQ ID NO: 2052.
• In some embodiments, the activatable antibody comprises a light chain comprising the amino acid sequence of SEQ ID NO: 2057; and a heavy chain comprising the amino acid sequence of SEQ ID NO: 2052.
• In some embodiments, the activatable antibody comprises a light chain comprising the amino acid sequence of SEQ ID NO: 2056; and a heavy chain comprising the amino acid sequence of SEQ ID NO: 2052.
• In some embodiments, the activatable antibody comprises a light chain comprising the amino acid sequence of SEQ ID NO: 2059; and a heavy chain comprising the amino acid sequence of SEQ ID NO: 2052.
• In some embodiments, the activatable antibody comprises a light chain comprising the amino acid sequence of SEQ ID NO: 2058; and a heavy chain comprising the amino acid sequence of SEQ ID NO: 2052.
• In some embodiments, the activatable antibody comprises a light chain comprising the amino acid sequence of SEQ ID NO: 2055; and a heavy chain comprising the amino acid sequence of SEQ ID NO: 2053.
• In some embodiments, the activatable antibody comprises a light chain comprising the amino acid sequence of SEQ ID NO: 2054; and a heavy chain comprising the amino acid sequence of SEQ ID NO: 2053.
• In some embodiments, the activatable antibody comprises a light chain comprising the amino acid sequence of SEQ ID NO: 2057; and a heavy chain comprising the amino acid sequence of SEQ ID NO: 2053.
• In some embodiments, the activatable antibody comprises a light chain comprising the amino acid sequence of SEQ ID NO: 2056; and a heavy chain comprising the amino acid sequence of SEQ ID NO: 2053.
• In some embodiments, the activatable antibody comprises a light chain comprising the amino acid sequence of SEQ ID NO: 2059; and a heavy chain comprising the amino acid sequence of SEQ ID NO: 2053.
• In some embodiments, the activatable antibody comprises a light chain comprising the amino acid sequence of SEQ ID NO: 2058; and a heavy chain comprising the amino acid sequence of SEQ ID NO: 2053.
• In some embodiments, the activatable antibody comprises a masking moiety (MM) comprising an amino acid sequence selected from the group consisting of SEQ ID NOs: 1351-1362; a cleavable moiety (CM) comprising an amino acid sequence selected from the group consisting of SEQ ID NOs: 214, 294, 300, 302, 303, 305, 308, 318, 347, 361, 1092-1102, 1111, and 1157; and a combination of a VH CDR1 sequence, a VH CDR2 sequence, a VH CDR3 sequence, a VL CDR1 sequence, a VL CDR2 sequence, and a VL CDR3 sequence, wherein the combination comprises the VH CDR sequences of the variable heavy chain sequence of SEQ ID NO: 1514 and the VL CDR sequences of the variable light chain sequence of SEQ ID NO: 638. In some embodiments, the combination further comprises a human immunoglobulin heavy chain constant region, a human immunoglobulin light chain constant domain, or both a human immunoglobulin heavy chain constant region and a human immunoglobulin light chain constant domain. In some embodiments, the human immunoglobulin heavy chain constant domain comprises an amino acid sequence selected from the group consisting of SEQ ID NO: 63, 381, 382, 383, and 1807. In some embodiments, the human immunoglobulin light chain constant domain is a human kappa constant domain comprising SEQ ID NO: 61 or SEQ ID NO: 1344.
• In some embodiments, the activatable antibody comprises a MM comprising an amino acid sequence selected from the group consisting of SEQ ID NOs: 1351-1362; a CM comprising an amino acid sequence selected from the group consisting of SEQ ID NOs: 214, 294, 300, 302, 303, 305, 308, 318, 347, 361, 1092-1102, 1111, and 1157; and a combination of a VH CDR1 sequence, a VH CDR2 sequence, a VH CDR3 sequence, a VL CDR1 sequence, a VL CDR2 sequence, and a VL CDR3 sequence, wherein the VH CDR1 sequence comprises GYTFTNYY (SEQ ID NO: 1711); the VH CDR2 sequence comprises INPSNGGT (SEQ ID NO: 1712); the VH CDR3 sequence comprises RRDYRFDMGFDY (SEQ ID NO: 1713); the VL CDR1 sequence comprises KGVSTSGYSY (SEQ ID NO: 1714); the VL CDR2 sequence comprises LAS (SEQ ID NO: 1715); and the VL CDR3 sequence comprises QHSRDLPLT (SEQ ID NO: 1716). In some embodiments, the combination further comprises a human immunoglobulin heavy chain constant region, a human immunoglobulin light chain constant domain, or both a human immunoglobulin heavy chain constant region and a human immunoglobulin light chain constant domain. In some embodiments, the human immunoglobulin heavy chain constant domain comprises an amino acid sequence selected from the group consisting of SEQ ID NO: 63, 381, 382, 383, and 1807. In some embodiments, the human immunoglobulin light chain constant domain is a human kappa constant domain comprising SEQ ID NO: 61 or SEQ ID NO: 1344.
• In some embodiments, the activatable antibody comprises a MM comprising an amino acid sequence selected from the group consisting of SEQ ID NOs: 1351-1362; a CM comprising an amino acid sequence selected from the group consisting of SEQ ID NOs: 214, 294, 300, 302, 303, 305, 308, 318, 347, 361, 1092-1102, 1111, and 1157; the VH sequence of SEQ ID NO: 1514 and the VL sequence of SEQ ID NO: 638. In some embodiments, the combination further comprises a human immunoglobulin heavy chain constant region, a human immunoglobulin light chain constant domain, or both a human immunoglobulin heavy chain constant region and a human immunoglobulin light chain constant domain. In some embodiments, the human immunoglobulin heavy chain constant domain comprises an amino acid sequence selected from the group consisting of SEQ ID NO: 63, 381, 382, 383, and 1807. In some embodiments, the human immunoglobulin light chain constant domain is a human kappa constant domain comprising SEQ ID NO: 61 or SEQ ID NO: 1344.
• In some embodiments, the activatable antibody comprises a MM comprising an amino acid sequence selected from the group consisting of SEQ ID NOs: 1206-1217; a CM comprising an amino acid sequence selected from the group consisting of SEQ ID NOs: 214, 294, 300, 302, 303, 305, 308, 318, 347, 361, 1092-1102, 1111, and 1157; and a combination of a VH CDR1 sequence, a VH CDR2 sequence, a VH CDR3 sequence, a VL CDR1 sequence, a VL CDR2 sequence, and a VL CDR3 sequence, wherein the combination comprises the VH CDR sequences of the variable heavy chain sequence of SEQ ID NO: 1346 and the VL CDR sequences of the variable light chain sequence of SEQ ID NO: 626. In some embodiments, the combination further comprises a human immunoglobulin heavy chain constant region, or both a human immunoglobulin heavy chain constant region and a human immunoglobulin light chain constant domain. In some embodiments, the human immunoglobulin heavy chain constant domain comprises an amino acid sequence selected from the group consisting of SEQ ID NO: 63, 381, 382, 383, and 1807. In some embodiments, the human immunoglobulin light chain constant domain is a human kappa constant domain comprising SEQ ID NO: 61 or SEQ ID NO: 1344.
• In some embodiments, the activatable antibody comprises a MM comprising an amino acid sequence selected from the group consisting of SEQ ID NOs: 1206-1217; a CM comprising an amino acid sequence selected from the group consisting of SEQ ID NOs: 214, 294, 300, 302, 303, 305, 308, 318, 347, 361, 1092-1102, 1111, and 1157; and a combination of a VH CDR1 sequence, a VH CDR2 sequence, a VH CDR3 sequence, a VL CDR1 sequence, a VL CDR2 sequence, and a VL CDR3 sequence, wherein the VH CDR1 sequence comprises GITFSNSG (SEQ ID NO: 1705); the VH CDR2 sequence comprises IWYDGSKR (SEQ ID NO: 1706); the VH CDR3 sequence comprises TNDDY (SEQ ID NO: 1707); the VL CDR1 sequence comprises QSVSSY (SEQ ID NO: 1708); the VL CDR2 sequence comprises DAS (SEQ ID NO: 1709); and the VL CDR3 sequence comprises QQSSNWPRT (SEQ ID NO: 1710). In some embodiments, the combination further comprises a human immunoglobulin heavy chain constant region, a human immunoglobulin light chain constant domain, or both a human immunoglobulin heavy chain constant region and a human immunoglobulin light chain constant domain. In some embodiments, the human immunoglobulin heavy chain constant domain comprises an amino acid sequence selected from the group consisting of SEQ ID NO: 63, 381, 382, 383, and 1807. In some embodiments, the human immunoglobulin light chain constant domain is a human kappa constant domain comprising SEQ ID NO: 61 or SEQ ID NO: 1344.
• In some embodiments, the activatable antibody comprises a MM comprising an amino acid sequence selected from the group consisting of SEQ ID NOs: 1206-1217; a CM comprising an amino acid sequence selected from the group consisting of SEQ ID NOs: 214, 294, 300, 302, 303, 305, 308, 318, 347, 361, 1092-1102, 1111, and 1157; the VH sequence of SEQ ID NO: 1346 and the VL sequence of SEQ ID NO: 626. In some embodiments, the combination further comprises a human immunoglobulin heavy chain constant region, a human immunoglobulin light chain constant domain, or both a human immunoglobulin heavy chain constant region and a human immunoglobulin light chain constant domain. In some embodiments, the human immunoglobulin heavy chain constant domain comprises an amino acid sequence selected from the group consisting of SEQ ID NO: 63, 381, 382, 383, and 1807. In some embodiments, the human immunoglobulin light chain constant domain is a human kappa constant domain comprising SEQ ID NO: 61 or SEQ ID NO: 1344.
• In some embodiments, the activatable antibody comprises a MM comprising the amino acid sequence ACRICQDHPATKWNS (SEQ ID NO: 549), a CM comprising the amino acid sequence ISSGLLSGRSANP (SEQ ID NO: 1101), which is also referred to herein as substrate 2012; the heavy chain (HC) sequence of SEQ ID NO: 546, and the light chain (LC) sequence of SEQ ID NO: 543.
• In some embodiments, the activatable antibody comprises a MM comprising the amino acid sequence ACRICQDHPATKWNS (SEQ ID NO: 549), a CM comprising the amino acid sequence ISSGLLSGRSDNP (SEQ ID NO: 1100), which is also referred to herein as substrate 2011; the heavy chain (HC) sequence of SEQ ID NO: 546, and the light chain (LC) sequence of SEQ ID NO: 543.
• In some embodiments, the activatable antibody comprises a MM comprising the amino acid sequence ACRICQDHPATKWNS (SEQ ID NO: 549), a CM comprising the amino acid sequence ISSGLLSGRSDNH (SEQ ID NO: 214), which is also referred to herein as substrate 2001; the heavy chain (HC) sequence of SEQ ID NO: 546, and the light chain (LC) sequence of SEQ ID NO: 543.
• In some embodiments, the activatable antibody comprises a MM comprising the amino acid sequence ACRICQDHPATKWNS (SEQ ID NO: 549), a CM comprising the amino acid sequence ISSGLLSGRSGNH (SEQ ID NO: 361), which is also referred to herein as substrate 2002; the heavy chain (HC) sequence of SEQ ID NO: 546, and the light chain (LC) sequence of SEQ ID NO: 543.
• In some embodiments, the activatable antibody comprises a MM comprising the amino acid sequence ACRICQDHPATKWNS (SEQ ID NO: 549), a CM comprising the amino acid sequence ISSGLLSGRSANPRG (SEQ ID NO: 1092), which is also referred to herein as substrate 2003; the heavy chain (HC) sequence of SEQ ID NO: 546, and the light chain (LC) sequence of SEQ ID NO: 543.
• In some embodiments, the activatable antibody comprises a MM comprising the amino acid sequence ACRICQDHPATKWNS (SEQ ID NO: 549), a CM comprising the amino acid sequence ISSGLLSGRSDDH (SEQ ID NO: 1095), which is also referred to herein as substrate 2006; the heavy chain (HC) sequence of SEQ ID NO: 546, and the light chain (LC) sequence of SEQ ID NO: 543.
• In some embodiments, the activatable antibody comprises a MM comprising the amino acid sequence ACRICQDHPATKWNS (SEQ ID NO: 549), a CM comprising the amino acid sequence ISSGLLSGRSDIH (SEQ ID NO: 1096), which is also referred to herein as substrate 2007; the heavy chain (HC) sequence of SEQ ID NO: 546, and the light chain (LC) sequence of SEQ ID NO: 543.
• In some embodiments, the activatable antibody comprises a MM comprising the amino acid sequence ACRICQDHPATKWNS (SEQ ID NO: 549), a CM comprising the amino acid sequence ISSGLLSGRSDQH (SEQ ID NO: 1097), which is also referred to herein as substrate 2008; the heavy chain (HC) sequence of SEQ ID NO: 546, and the light chain (LC) sequence of SEQ ID NO: 543.
• In some embodiments, the activatable antibody comprises a MM comprising the amino acid sequence ACRICQDHPATKWNS (SEQ ID NO: 549), a CM comprising the amino acid sequence ISSGLLSGRSDTH (SEQ ID NO: 1098), which is also referred to herein as substrate 2009; the heavy chain (HC) sequence of SEQ ID NO: 546, and the light chain (LC) sequence of SEQ ID NO: 543.
• In some embodiments, the activatable antibody comprises a MM comprising the amino acid sequence ACRICQDHPATKWNS (SEQ ID NO: 549), a CM comprising the amino acid sequence ISSGLLSGRSDQH (SEQ ID NO: 1099), which is also referred to herein as substrate 2010; the heavy chain (HC) sequence of SEQ ID NO: 546, and the light chain (LC) sequence of SEQ ID NO: 543.
• In some embodiments, the activatable antibody comprises a MM comprising the amino acid sequence ACRICQDHPATKWNS (SEQ ID NO: 549), a CM comprising the amino acid sequence ISSGLLSGRSANI (SEQ ID NO: 1102), which is also referred to herein as substrate 2013; the heavy chain (HC) sequence of SEQ ID NO: 546, and the light chain (LC) sequence of SEQ ID NO: 543.
• In some embodiments, the activatable antibody comprises a MM comprising the amino acid sequence ACRICQDHPATKWNS (SEQ ID NO: 549), a CM comprising the amino acid sequence ISSGLLSGRSDNI (SEQ ID NO: 1111), which is also referred to herein as substrate 2014; the heavy chain (HC) sequence of SEQ ID NO: 546, and the light chain (LC) sequence of SEQ ID NO: 543.
• In some embodiments, the activatable antibody comprises a MM comprising the amino acid sequence ACRICQDHPATKWNS (SEQ ID NO: 549), a CM comprising the amino acid sequence ISSGLLSGRSANP (SEQ ID NO: 1101), which is also referred to herein as substrate 2012; the variable heavy chain region (VH) of the heavy chain (HC) sequence of SEQ ID NO: 546, and the variable light chain region (VL) of the light chain (LC) sequence of SEQ ID NO: 543.
• In some embodiments, the activatable antibody comprises a MM comprising the amino acid sequence ACRICQDHPATKWNS (SEQ ID NO: 549), a CM comprising the amino acid sequence ISSGLLSGRSDNP (SEQ ID NO: 1100), which is also referred to herein as substrate 2011; the variable heavy chain region (VH) of the heavy chain (HC) sequence of SEQ ID NO: 546, and the variable light chain region (VL) of the light chain (LC) sequence of SEQ ID NO: 543.
• In some embodiments, the activatable antibody comprises a MM comprising the amino acid sequence ACRICQDHPATKWNS (SEQ ID NO: 549), a CM comprising the amino acid sequence ISSGLLSGRSDNH (SEQ ID NO: 214), which is also referred to herein as substrate 2001; the variable heavy chain region (VH) of the heavy chain (HC) sequence of SEQ ID NO: 546, and the variable light chain region (VL) of the light chain (LC) sequence of SEQ ID NO: 543.
• In some embodiments, the activatable antibody comprises a MM comprising the amino acid sequence ACRICQDHPATKWNS (SEQ ID NO: 549), a CM comprising the amino acid sequence ISSGLLSGRSGNH (SEQ ID NO: 361), which is also referred to herein as substrate 2002; the variable heavy chain region (VH) of the heavy chain (HC) sequence of SEQ ID NO: 546, and the variable light chain region (VL) of the light chain (LC) sequence of SEQ ID NO: 543.
• In some embodiments, the activatable antibody comprises a MM comprising the amino acid sequence ACRICQDHPATKWNS (SEQ ID NO: 549), a CM comprising the amino acid sequence ISSGLLSGRSANPRG (SEQ ID NO: 1092), which is also referred to herein as substrate 2003; the variable heavy chain region (VH) of the heavy chain (HC) sequence of SEQ ID NO: 546, and the variable light chain region (VL) of the light chain (LC) sequence of SEQ ID NO: 543.
• In some embodiments, the activatable antibody comprises a MM comprising the amino acid sequence ACRICQDHPATKWNS (SEQ ID NO: 549), a CM comprising the amino acid sequence ISSGLLSGRSDDH (SEQ ID NO: 1095), which is also referred to herein as substrate 2006; the variable heavy chain region (VH) of the heavy chain (HC) sequence of SEQ ID NO: 546, and the variable light chain region (VL) of the light chain (LC) sequence of SEQ ID NO: 543.
• In some embodiments, the activatable antibody comprises a MM comprising the amino acid sequence ACRICQDHPATKWNS (SEQ ID NO: 549), a CM comprising the amino acid sequence ISSGLLSGRSDIH (SEQ ID NO: 1096), which is also referred to herein as substrate 2007; the variable heavy chain region (VH) of the heavy chain (HC) sequence of SEQ ID NO: 546, and the variable light chain region (VL) of the light chain (LC) sequence of SEQ ID NO: 543.
• In some embodiments, the activatable antibody comprises a MM comprising the amino acid sequence ACRICQDHPATKWNS (SEQ ID NO: 549), a CM comprising the amino acid sequence ISSGLLSGRSDQH (SEQ ID NO: 1097), which is also referred to herein as substrate 2008; the variable heavy chain region (VH) of the heavy chain (HC) sequence of SEQ ID NO: 546, and the variable light chain region (VL) of the light chain (LC) sequence of SEQ ID NO: 543.
• In some embodiments, the activatable antibody comprises a MM comprising the amino acid sequence ACRICQDHPATKWNS (SEQ ID NO: 549), a CM comprising the amino acid sequence ISSGLLSGRSDTH (SEQ ID NO: 1098), which is also referred to herein as substrate 2009; the variable heavy chain region (VH) of the heavy chain (HC) sequence of SEQ ID NO: 546, and the variable light chain region (VL) of the light chain (LC) sequence of SEQ ID NO: 543.
• In some embodiments, the activatable antibody comprises a MM comprising the amino acid sequence ACRICQDHPATKWNS (SEQ ID NO: 549), a CM comprising the amino acid sequence ISSGLLSGRSDYH (SEQ ID NO: 1099), which is also referred to herein as substrate 2010; the variable heavy chain region (VH) of the heavy chain (HC) sequence of SEQ ID NO: 546, and the variable light chain region (VL) of the light chain (LC) sequence of SEQ ID NO: 543.
• In some embodiments, the activatable antibody comprises a MM comprising the amino acid sequence ACRICQDHPATKWNS (SEQ ID NO: 549), a CM comprising the amino acid sequence ISSGLLSGRSANI (SEQ ID NO: 1102), which is also referred to herein as substrate 2013; the variable heavy chain region (VH) of the heavy chain (HC) sequence of SEQ ID NO: 546, and the variable light chain region (VL) of the light chain (LC) sequence of SEQ ID NO: 543.
• In some embodiments, the activatable antibody comprises a MM comprising the amino acid sequence ACRICQDHPATKWNS (SEQ ID NO: 549), a CM comprising the amino acid sequence ISSGLLSGRSDNI (SEQ ID NO: 1111), which is also referred to herein as substrate 2014; the variable heavy chain region (VH) of the heavy chain (HC) sequence of SEQ ID NO: 546, and the variable light chain region (VL) of the light chain (LC) sequence of SEQ ID NO: 543.
• In some embodiments, the activatable antibody comprises a MM comprising the amino acid sequence ACRICQDHPATKWNS (SEQ ID NO: 549), a CM comprising the amino acid sequence ISSGLLSGRSANP (SEQ ID NO: 1101), which is also referred to herein as substrate 2012; the heavy chain complementarity determining regions (CDRs) of the heavy chain (HC) sequence of SEQ ID NO: 546, and the light chain complementarity determining regions (CDRs) of the light chain (LC) sequence of SEQ ID NO: 543.
• In some embodiments, the activatable antibody comprises a MM comprising the amino acid sequence ACRICQDHPATKWNS (SEQ ID NO: 549), a CM comprising the amino acid sequence ISSGLLSGRSDNP (SEQ ID NO: 1100), which is also referred to herein as substrate 2011; the heavy chain complementarity determining regions (CDRs) of the heavy chain (HC) sequence of SEQ ID NO: 546, and the light chain complementarity determining regions (CDRs) of the light chain (LC) sequence of SEQ ID NO: 543.
• In some embodiments, the activatable antibody comprises a MM comprising the amino acid sequence ACRICQDHPATKWNS (SEQ ID NO: 549), a CM comprising the amino acid sequence ISSGLLSGRSDNH (SEQ ID NO: 214), which is also referred to herein as substrate 2001; the heavy chain complementarity determining regions (CDRs) of the heavy chain (HC) sequence of SEQ ID NO: 546, and the light chain complementarity determining regions (CDRs) of the light chain (LC) sequence of SEQ ID NO: 543.
• In some embodiments, the activatable antibody comprises a MM comprising the amino acid sequence ACRICQDHPATKWNS (SEQ ID NO: 549), a CM comprising the amino acid sequence ISSGLLSGRSGNH (SEQ ID NO: 361), which is also referred to herein as substrate 2002; the heavy chain complementarity determining regions (CDRs) of the heavy chain (HC) sequence of SEQ ID NO: 546, and the light chain complementarity determining regions (CDRs) of the light chain (LC) sequence of SEQ ID NO: 543.
• In some embodiments, the activatable antibody comprises a MM comprising the amino acid sequence ACRICQDHPATKWNS (SEQ ID NO: 549), a CM comprising the amino acid sequence ISSGLLSGRSANPRG (SEQ ID NO: 1092), which is also referred to herein as substrate 2003; the heavy chain complementarity determining regions (CDRs) of the heavy chain (HC) sequence of SEQ ID NO: 546, and the light chain complementarity determining regions (CDRs) of the light chain (LC) sequence of SEQ ID NO: 543.
• In some embodiments, the activatable antibody comprises a MM comprising the amino acid sequence ACRICQDHPATKWNS (SEQ ID NO: 549), a CM comprising the amino acid sequence ISSGLLSGRSDDH (SEQ ID NO: 1095), which is also referred to herein as substrate 2006; the heavy chain complementarity determining regions (CDRs) of the heavy chain (HC) sequence of SEQ ID NO: 546, and the light chain complementarity determining regions (CDRs) of the light chain (LC) sequence of SEQ ID NO: 543.
• In some embodiments, the activatable antibody comprises a MM comprising the amino acid sequence ACRICQDHPATKWNS (SEQ ID NO: 549), a CM comprising the amino acid sequence ISSGLLSGRSDIH (SEQ ID NO: 1096), which is also referred to herein as substrate 2007; the heavy chain complementarity determining regions (CDRs) of the heavy chain (HC) sequence of SEQ ID NO: 546, and the light chain complementarity determining regions (CDRs) of the light chain (LC) sequence of SEQ ID NO: 543.
• In some embodiments, the activatable antibody comprises a MM comprising the amino acid sequence ACRICQDHPATKWNS (SEQ ID NO: 549), a CM comprising the amino acid sequence ISSGLLSGRSDQH (SEQ ID NO: 1097), which is also referred to herein as substrate 2008; the heavy chain complementarity determining regions (CDRs) of the heavy chain (HC) sequence of SEQ ID NO: 546, and the light chain complementarity determining regions (CDRs) of the light chain (LC) sequence of SEQ ID NO: 543.
• In some embodiments, the activatable antibody comprises a MM comprising the amino acid sequence ACRICQDHPATKWNS (SEQ ID NO: 549), a CM comprising the amino acid sequence ISSGLLSGRSDTH (SEQ ID NO: 1098), which is also referred to herein as substrate 2009; the heavy chain complementarity determining regions (CDRs) of the heavy chain (HC) sequence of SEQ ID NO: 546, and the light chain complementarity determining regions (CDRs) of the light chain (LC) sequence of SEQ ID NO: 543.
• In some embodiments, the activatable antibody comprises a MM comprising the amino acid sequence ACRICQDHPATKWNS (SEQ ID NO: 549), a CM comprising the amino acid sequence ISSGLLSGRSDYH (SEQ ID NO: 1099), which is also referred to herein as substrate 2010; the heavy chain complementarity determining regions (CDRs) of the heavy chain (HC) sequence of SEQ ID NO: 546, and the light chain complementarity determining regions (CDRs) of the light chain (LC) sequence of SEQ ID NO: 543.
• In some embodiments, the activatable antibody comprises a MM comprising the amino acid sequence ACRICQDHPATKWNS (SEQ ID NO: 549), a CM comprising the amino acid sequence ISSGLLSGRSANI (SEQ ID NO: 1102), which is also referred to herein as substrate 2013; the heavy chain complementarity determining regions (CDRs) of the heavy chain (HC) sequence of SEQ ID NO: 546, and the light chain complementarity determining regions (CDRs) of the light chain (LC) sequence of SEQ ID NO: 543.
• In some embodiments, the activatable antibody comprises a MM comprising the amino acid sequence ACRICQDHPATKWNS (SEQ ID NO: 549), a CM comprising the amino acid sequence ISSGLLSGRSDNI (SEQ ID NO: 1111), which is also referred to herein as substrate 2014; the heavy chain complementarity determining regions (CDRs) of the heavy chain (HC) sequence of SEQ ID NO: 546, and the light chain complementarity determining regions (CDRs) of the light chain (LC) sequence of SEQ ID NO: 543.
• In some embodiments, the activatable antibody comprises a light chain comprising an amino acid sequence selected from the group consisting of SEQ ID NOs: 1808, 1810, 1812, 1814, 1816, 1818, 1820, 1822, 1824, 1826, 1828, and 1830; and a heavy chain comprising the amino acid sequence of SEQ ID NO: 546.
• In some embodiments, the activatable antibody comprises a light chain comprising the amino acid sequence of SEQ ID NO: 1808; and a heavy chain comprising the amino acid sequence of SEQ ID NO: 546.
• In some embodiments, the activatable antibody comprises a light chain comprising the amino acid sequence of SEQ ID NO: 1810; and a heavy chain comprising the amino acid sequence of SEQ ID NO: 546.
• In some embodiments, the activatable antibody comprises a light chain comprising the amino acid sequence of SEQ ID NO: 1812; and a heavy chain comprising the amino acid sequence of SEQ ID NO: 546.
• In some embodiments, the activatable antibody comprises a light chain comprising the amino acid sequence of SEQ ID NO: 1814; and a heavy chain comprising the amino acid sequence of SEQ ID NO: 546.
• In some embodiments, the activatable antibody comprises a light chain comprising the amino acid sequence of SEQ ID NO: 1816; and a heavy chain comprising the amino acid sequence of SEQ ID NO: 546.
• In some embodiments, the activatable antibody comprises a light chain comprising the amino acid sequence of SEQ ID NO: 1818; and a heavy chain comprising the amino acid sequence of SEQ ID NO: 546.
• In some embodiments, the activatable antibody comprises a light chain comprising the amino acid sequence of SEQ ID NO: 1820; and a heavy chain comprising the amino acid sequence of SEQ ID NO: 546.
• In some embodiments, the activatable antibody comprises a light chain comprising the amino acid sequence of SEQ ID NO: 1822; and a heavy chain comprising the amino acid sequence of SEQ ID NO: 546.
• In some embodiments, the activatable antibody comprises a light chain comprising the amino acid sequence of SEQ ID NO: 1824; and a heavy chain comprising the amino acid sequence of SEQ ID NO: 546.
• In some embodiments, the activatable antibody comprises a light chain comprising the amino acid sequence of SEQ ID NO: 1826; and a heavy chain comprising the amino acid sequence of SEQ ID NO: 546.
• In some embodiments, the activatable antibody comprises a light chain comprising the amino acid sequence of SEQ ID NO: 1828; and a heavy chain comprising the amino acid sequence of SEQ ID NO: 546.
• In some embodiments, the activatable antibody comprises a light chain comprising the amino acid sequence of SEQ ID NO: 1830; and a heavy chain comprising the amino acid sequence of SEQ ID NO: 546.
• In some embodiments, the activatable antibody is encoded by a nucleic acid sequence that comprises a nucleic acid sequence encoding a heavy chain amino acid sequence selected from the group consisting of SEQ ID NO: 1, 5, 9, 13, 17, 21, 23, 25, 27, 29, 31, 33, 35, and 37. In some embodiments, the activatable antibody is encoded by a nucleic acid sequence that comprises a nucleic acid sequence encoding a heavy chain amino acid sequence selected from the group consisting of SEQ ID NO: 21, 23, 25, 27, 29, 31, 33, 35, and 37.
• In some embodiments, the activatable antibody is encoded by a nucleic acid sequence that comprises a nucleic acid sequence encoding a light chain amino acid sequence selected from the group consisting of SEQ ID NO: 3, 7, 11, 15, 19, 39, 41, 43, 45, 47, 49, 51, 53, 55, 57, and 59. In some embodiments, the activatable antibody is encoded by a nucleic acid sequence that comprises a nucleic acid sequence encoding a light chain amino acid sequence selected from the group consisting of SEQ ID NO: 39, 41, 43, 45, 47, 49, 51, 53, 55, 57, and 59.
• In some embodiments, the activatable antibody is encoded by a nucleic acid sequence that comprises a nucleic acid sequence encoding a heavy chain amino acid sequence selected from the group consisting of SEQ ID NO: 1, 5, 9, 13, 17, 21, 23, 25, 27, 29, 31, 33, 35, and 37, and a nucleic acid sequence that comprises a nucleic acid sequence encoding a light chain amino acid sequence selected from the group consisting of SEQ ID NO: 3, 7, 11, 15, 19, 39, 41, 43, 45, 47, 49, 51, 53, 55, 57, and 59.
• In some embodiments, the activatable antibody is encoded by a nucleic acid sequence that comprises a nucleic acid sequence encoding a heavy chain amino acid sequence selected from the group consisting of SEQ ID NO: 21, 23, 25, 27, 29, 31, 33, 35, and 37, and a nucleic acid sequence that comprises a nucleic acid sequence encoding a light chain amino acid sequence selected from the group consisting of SEQ ID NO: 39, 41, 43, 45, 47, 49, 51, 53, 55, 57, and 59.
• In some embodiments, the activatable antibody is encoded by a nucleic acid sequence that comprises a nucleic acid sequence encoding a heavy chain amino acid sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to an amino acid sequence selected from the group consisting of SEQ ID NO: 1, 5, 9, 13, 17, 21, 23, 25, 27, 29, 31, 33, 35, and 37. In some embodiments, the activatable antibody is encoded by a nucleic acid sequence that comprises a nucleic acid sequence encoding a heavy chain amino acid sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to an amino acid sequence selected from the group consisting of SEQ ID NO: 21, 23, 25, 27, 29, 31, 33, 35, and 37.
• In some embodiments, the activatable antibody is encoded by a nucleic acid sequence that comprises a nucleic acid sequence encoding a light chain amino acid that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to the amino acid sequence selected from the group consisting of SEQ ID NO: 3, 7, 11, 15, 19, 39, 41, 43, 45, 47, 49, 51, 53, 55, 57, and 59. In some embodiments, the activatable antibody is encoded by a nucleic acid sequence that comprises a nucleic acid sequence encoding a light chain amino acid that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to the amino acid sequence selected from the group consisting of SEQ ID NO: 39, 41, 43, 45, 47, 49, 51, 53, 55, 57, and 59.
• In some embodiments, the activatable antibody is encoded by a nucleic acid sequence that comprises a nucleic acid sequence encoding a heavy chain amino acid sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to an amino acid sequence selected from the group consisting of SEQ ID NO: 1, 5, 9, 13, 17, 21, 23, 25, 27, 29, 31, 33, 35, and 37, and a nucleic acid sequence encoding a light chain amino acid that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to the amino acid sequence selected from the group consisting of SEQ ID NO: 3, 7, 11, 15, 19, 39, 41, 43, 45, 47, 49, 51, 53, 55, 57, and 59.
• In some embodiments, the activatable antibody is encoded by a nucleic acid sequence that comprises a nucleic acid sequence encoding a heavy chain amino acid sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to an amino acid sequence selected from the group consisting of SEQ ID NO: 21, 23, 25, 27, 29, 31, 33, 35, and 37, and a nucleic acid sequence that comprises a nucleic acid sequence encoding a light chain amino acid that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to the amino acid sequence selected from the group consisting of SEQ ID NO: 39, 41, 43, 45, 47, 49, 51, 53, 55, 57, and 59.
• In some embodiments, the activatable antibody is encoded by a heavy chain nucleic acid sequence selected from the group consisting of SEQ ID NO: 2, 6, 10, 14, 18, 22, 24, 26, 28, 30, 32, 34, 36, and 38. In some embodiments, the activatable antibody is encoded by a heavy chain nucleic acid sequence selected from the group consisting of SEQ ID NO: 22, 24, 26, 28, 30, 32, 34, 36, and 38.
• In some embodiments, the activatable antibody is encoded by a light chain nucleic acid sequence selected from the group consisting of SEQ ID NO: 4, 8, 12, 16, 20, 40, 42, 44, 46, 48, 50, 52, 54, 56, 58, and 60. In some embodiments, the activatable antibody is encoded by a light chain nucleic acid sequence selected from the group consisting of SEQ ID NO: 40, 42, 44, 46, 48, 50, 52, 54, 56, 58, and 60.
• In some embodiments, the activatable antibody is encoded by heavy chain nucleic acid sequence selected from the group consisting of SEQ ID NO: selected from the group consisting of SEQ ID NO: 2, 6, 10, 14, 18, 22, 24, 26, 28, 30, 32, 34, 36, and 38, and a light chain nucleic acid sequence selected from the group consisting of SEQ ID NO: 4, 8, 12, 16, 20, 40, 42, 44, 46, 48, 50, 52, 54, 56, 58, and 60. In some embodiments, the activatable antibody is encoded by heavy chain nucleic acid sequence selected from the group consisting of SEQ ID NO: selected from the group consisting of SEQ ID NO: 22, 24, 26, 28, 30, 32, 34, 36, and 38, and a light chain nucleic acid sequence selected from the group consisting of SEQ ID NO: 40, 42, 44, 46, 48, 50, 52, 54, 56, 58, and 60.
• In some embodiments, the activatable antibody is encoded by a nucleic acid sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to a heavy chain nucleic acid sequence selected from the group consisting of SEQ ID NO: 2, 6, 10, 14, 18, 22, 24, 26, 28, 30, 32, 34, 36, and 38. In some embodiments, the activatable antibody is encoded by a nucleic acid sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to a heavy chain nucleic acid sequence selected from the group consisting of SEQ ID NO: 22, 24, 26, 28, 30, 32, 34, 36, and 38.
• In some embodiments, the activatable antibody is encoded by a nucleic acid sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to a light chain nucleic acid sequence selected from the group consisting of SEQ ID NO: 4, 8, 12, 16, 20, 40, 42, 44, 46, 48, 50, 52, 54, 56, 58, and 60. In some embodiments, the activatable antibody is encoded by a nucleic acid sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to a light chain nucleic acid sequence selected from the group consisting of SEQ ID NO: 40, 42, 44, 46, 48, 50, 52, 54, 56, 58, and 60.
• In some embodiments, the activatable antibody is encoded by a nucleic acid sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to a heavy chain nucleic acid sequence selected from the group consisting of SEQ ID NO: 2, 6, 10, 14, 18, 22, 24, 26, 28, 30, 32, 34, 36, and 38, and a nucleic acid sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to a light chain nucleic acid sequence selected from the group consisting of SEQ ID NO: 4, 8, 12, 16, 20, 40, 42, 44, 46, 48, 50, 52, 54, 56, 58, and 60. In some embodiments, the activatable antibody is encoded by a nucleic acid sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to a heavy chain nucleic acid sequence selected from the group consisting of SEQ ID NO: 22, 24, 26, 28, 30, 32, 34, 36, and 38, and a nucleic acid sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to a light chain nucleic acid sequence selected from the group consisting of SEQ ID NO: 40, 42, 44, 46, 48, 50, 52, 54, 56, 58, and 60.
• In some embodiments, the MM has a dissociation constant, i.e., dissociation constant at an equilibrium state, K_d for binding to the AB that is greater than the K_d for binding of the AB to PD-1.
• In some embodiments, the MM has a K_d for binding to the AB that is no more than the K_d for binding of the AB to PD-1.
• In some embodiments, the MM has a K_d for binding to the AB that is no less than the K_d for binding of the AB to PD-1.
• In some embodiments, the MM has a K_d for binding to the AB that is approximately equal to the K_d for binding of the AB to PD-1.
• In some embodiments, the MM has a K_d for binding to the AB that is less than the K_d for binding of the AB to PD-1.
• In some embodiments, the MM has a K_d for binding to the AB that is no more than 2, 3, 4, 5, 10, 25, 50, 100, 250, 500, or 1,000 fold greater than the K_d for binding of the AB to PD-1. In some embodiments, the MM has a K_d for binding to the AB that is between 1-5, 2-5, 2-10, 5-10, 5-20, 5-50, 5-100, 10-100, 10-1,000, 20-100, 20-1000, or 100-1,000 fold greater than the K_d for binding of the AB to PD-1.
• In some embodiments, the MM has an affinity for binding to the AB that is less than the affinity of binding of the AB to PD-1.
• In some embodiments, the MM has an affinity for binding to the AB that is no more than the affinity of binding of the AB to PD-1.
• In some embodiments, the MM has an affinity for binding to the AB that is approximately equal of the affinity of binding of the AB to PD-1.
• In some embodiments, the MM has an affinity for binding to the AB that is no less than the affinity of binding of the AB to PD-1.
• In some embodiments, the MM has an affinity for binding to the AB that is greater than the affinity of binding of the AB to PD-1.
• In some embodiments, the MM has an affinity for binding to the AB that is 2, 3, 4, 5, 10, 25, 50, 100, 250, 500, or 1,000 less than the affinity of binding of the AB to PD-1. I In some embodiments, the MM has an affinity for binding to the AB that is between 1-5, 2-5, 2-10, 5-10, 5-20, 5-50, 5-100, 10-100, 10-1,000, 20-100, 20-1000, or 100-1,000 fold less than the affinity of binding of the AB to PD-1. In some embodiments, the MM has an affinity for binding to the AB that is 2 to 20 fold less than the affinity of binding of the AB to PD-1. In some embodiments, a MM not covalently linked to the AB and at equimolar concentration to the AB does not inhibit the binding of the AB to PD-1.
• In some embodiments, the MM does not interfere or compete with the AB for binding to PD-1 when the activatable antibody is in a cleaved state.
• In some embodiments, the MM is a polypeptide of about 2 to 40 amino acids in length. In some embodiments, the MM is a polypeptide of up to about 40 amino acids in length.
• In some embodiments, the MM is a polypeptide of no more than 40 amino acids in length.
• In some embodiments, the MM polypeptide sequence is different from that of PD-1. In some embodiments, the MM polypeptide sequence is different from that of human PD-1. In some embodiments, the MM polypeptide sequence is no more than 50% identical to any natural binding partner of the AB. In some embodiments, the MM polypeptide sequence is different from that of PD-1 and is no more than 40%, 30%, 25%, 20%, 15%, or 10% identical to any natural binding partner of the AB. In some embodiments, the MM polypeptide sequence is no more than 50% identical to human PD-1. In some embodiments, the MM polypeptide sequence is different from that of PD-1 and is no more than 40%, 30%, 25%, 20%, 15%, or 10% identical to human PD-1.
• In some embodiments, the MM comprises an amino acid sequence selected from the group consisting of SEQ ID NOs: 66-213, 384-514, 548-571, 1206-1295, and 1351-1465. In some embodiments, the MM comprises an amino acid sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to an amino acid sequence selected from the group consisting of SEQ ID NOs: 66-213, 384-514, 548-571, 1206-1295, and 1351-1465. In some embodiments, the MM comprises an amino acid sequence selected from the group consisting of SEQ ID NOs: 66, 67, 70, 71, 74, 77, 81, 82, 84, 90, 91, 93, and 99. In some embodiments, the MM comprises an amino acid sequence selected from the group consisting of SEQ ID NOs: 66, 71, 74, 77, 82, 84, 90, 91, 93, and 99. In some embodiments, the MM comprises an amino acid sequence selected from the group consisting of SEQ ID NOs: 1206-1217. In some embodiments, the MM comprises an amino acid sequence selected from the group consisting of SEQ ID NOs: 1351-1362.
• In some embodiments, the MM comprises an amino acid sequence selected from the group consisting of SEQ ID NOs: 66-213. In some embodiments, the MM comprises an amino acid sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to an amino acid sequence selected from the group consisting of SEQ ID NOs: 66-213.
• In some embodiments, the MM comprises an amino acid sequence selected from the group consisting of SEQ ID NOs: 384-514. In some embodiments, the MM comprises an amino acid sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to an amino acid sequence selected from the group consisting of SEQ ID NOs: 384-514.
• In some embodiments, the MM comprises an amino acid sequence selected from the group consisting of SEQ ID NOs: 548-571. In some embodiments, the MM comprises an amino acid sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to an amino acid sequence selected from the group consisting of SEQ ID NOs: 548-571.
• In some embodiments, the MM comprises an amino acid sequence selected from the group consisting of SEQ ID NOs: 1206-1295. In some embodiments, the MM comprises an amino acid sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to an amino acid sequence selected from the group consisting of SEQ ID NOs: 1206-1295.
• In some embodiments, the MM comprises an amino acid sequence selected from the group consisting of SEQ ID NOs: 1351-1465. In some embodiments, the MM comprises an amino acid sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to an amino acid sequence selected from the group consisting of SEQ ID NOs: 1351-1465.
• In some embodiments, the antibody or activatable antibody comprises a heavy chain comprising an amino acid selected from the group consisting of SEQ ID NOs: 2052 and 2053.
• In some embodiments, the antibody or activatable antibody comprises a light chain comprising an amino acid selected from the group consisting of SEQ ID NOs: 2054 to 2059.
• In some embodiments, the antibody or activatable antibody comprises a heavy chain comprising an amino acid selected from the group consisting of SEQ ID NOs: 2052 and 2053 and a light chain comprising an amino acid selected from the group consisting of SEQ ID NOs: 2054 to 2059.
• In some embodiments, the coupling of the MM to the AB reduces the ability of the AB to bind PD-1 such that the dissociation constant (K_d) of the AB when coupled to the MM towards PD-1 is at least two times greater than the K_d of the AB when not coupled to the MM towards PD-1.
• In some embodiments, the coupling of the MM to the AB reduces the ability of the AB to bind PD-1 such that the dissociation constant (K_d) of the AB when coupled to the MM towards PD-1 is at least five times greater than the K_d of the AB when not coupled to the MM towards PD-1.
• In some embodiments, the coupling of the MM to the AB reduces the ability of the AB to bind PD-1 such that the dissociation constant (K_d) of the AB when coupled to the MM towards PD-1 is at least 10 times greater than the K_d of the AB when not coupled to the MM towards PD-1.
• In some embodiments, the coupling of the MM to the AB reduces the ability of the AB to bind PD-1 such that the dissociation constant (K_d) of the AB when coupled to the MM towards PD-1 is at least 20 times greater than the K_d of the AB when not coupled to the MM towards PD-1.
• In some embodiments, the coupling of the MM to the AB reduces the ability of the AB to bind PD-1 such that the dissociation constant (K_d) of the AB when coupled to the MM towards PD-1 is at least 40 times greater than the K_d of the AB when not coupled to the MM towards PD-1.
• In some embodiments, the coupling of the MM to the AB reduces the ability of the AB to bind PD-1 such that the dissociation constant (K_d) of the AB when coupled to the MM towards PD-1 is at least 100 times greater than the K_d of the AB when not coupled to the MM towards PD-1.
• In some embodiments, the coupling of the MM to the AB reduces the ability of the AB to bind PD-1 such that the dissociation constant (K_d) of the AB when coupled to the MM towards PD-1 is at least 1000 times greater than the K_d of the AB when not coupled to the MM towards PD-1.
• In some embodiments, the coupling of the MM to the AB reduces the ability of the AB to bind PD-1 such that the dissociation constant (K_d) of the AB when coupled to the MM towards PD-1 is at least 10,000 times greater than the K_d of the AB when not coupled to the MM towards PD-1.
• In some embodiments, in the presence of PD-1, the MM reduces the ability of the AB to bind PD-1 by at least 90% when the CM is uncleaved, as compared to when the CM is cleaved when assayed in vitro using a target displacement assay such as, for example, the assay described in PCT Publication No. WO 2010/081173, the contents of which are hereby incorporated by reference in their entirety.
• In some embodiments, the protease that cleaves the CM is active, e.g., up-regulated, in diseased tissue, and the protease cleaves the CM in the activatable antibody when the activatable antibody is exposed to the protease.
• In some embodiments, the protease is produced by a tumor that is in proximity to T cells that express PD-1, and the protease cleaves the CM in the activatable antibody when the activatable antibody is exposed to the protease. In some embodiments, the protease is produced by a tumor that is co-localized with T cells that express PD-1, and the protease cleaves the CM in the activatable antibody when the activatable antibody is exposed to the protease.
• In some embodiments, the CM is positioned in the activatable antibody such that when the activatable antibody is in the uncleaved state, binding of the activatable antibody to PD-1 is reduced to occur with a dissociation constant that is at least twofold greater than the dissociation constant of an unmodified AB binding to PD-1, whereas in the cleaved state (i.e., when the activatable antibody is in the cleaved state), the AB binds PD-1.
• In some embodiments, the CM is positioned in the activatable antibody such that when the activatable antibody is in the uncleaved state, binding of the activatable antibody to PD-1 is reduced to occur with a dissociation constant that is at least fivefold greater than the dissociation constant of an unmodified AB binding to PD-1, whereas in the cleaved state (i.e., when the activatable antibody is in the cleaved state), the AB binds PD-1.
• In some embodiments, the CM is positioned in the activatable antibody such that when the activatable antibody is in the uncleaved state, binding of the activatable antibody to PD-1 is reduced to occur with a dissociation constant that is at least 10-fold greater than the dissociation constant of an unmodified AB binding to PD-1, whereas in the cleaved state (i.e., when the activatable antibody is in the cleaved state), the AB binds PD-1.
• In some embodiments, the CM is positioned in the activatable antibody such that when the activatable antibody is in the uncleaved state, binding of the activatable antibody to PD-1 is reduced to occur with a dissociation constant that is at least 20-fold greater than the dissociation constant of an unmodified AB binding to PD-1, whereas in the cleaved state (i.e., when the activatable antibody is in the cleaved state), the AB binds PD-1.
• In some embodiments, the CM is positioned in the activatable antibody such that when the activatable antibody is in the uncleaved state, binding of the activatable antibody to PD-1 is reduced to occur with a dissociation constant that is at least 40-fold greater than the dissociation constant of an unmodified AB binding to PD-1, whereas in the cleaved state, the AB binds PD-1.
• In some embodiments, the CM is positioned in the activatable antibody such that when the activatable antibody is in the uncleaved state, binding of the activatable antibody to PD-1 is reduced to occur with a dissociation constant that is at least 50-fold greater than the dissociation constant of an unmodified AB binding to PD-1, whereas in the cleaved state, the AB binds PD-1.
• In some embodiments, the CM is positioned in the activatable antibody such that when the activatable antibody is in the uncleaved state, binding of the activatable antibody to PD-1 is reduced to occur with a dissociation constant that is at least 100-fold greater than the dissociation constant of an unmodified AB binding to PD-1, whereas in the cleaved state, the AB binds PD-1.
• In some embodiments, the CM is positioned in the activatable antibody such that when the activatable antibody is in the uncleaved state, binding of the activatable antibody to PD-1 is reduced to occur with a dissociation constant that is at least 200-fold greater than the dissociation constant of an unmodified AB binding to PD-1, whereas in the cleaved state, the AB binds PD-1.
• In some embodiments, the CM is a polypeptide of up to 15 amino acids in length.
• In some embodiments, the CM is a polypeptide that includes a first cleavable moiety (CM1) that is a substrate for at least one matrix metalloprotease (MMP) and a second cleavable moiety (CM2) that is a substrate for at least one serine protease (SP). In some embodiments, each of the CM1 substrate sequence and the CM2 substrate sequence of the CM1-CM2 substrate is independently a polypeptide of up to 15 amino acids in length.
• In some embodiments, the CM is a substrate for at least one protease that is or is believed to be up-regulated in cancer. In some embodiments, the CM is a substrate for at least one protease that is or is believed to be up-regulated in inflammation. In some embodiments, the CM is a substrate for at least one protease that is or is believed to be up-regulated in autoimmunity.
• In some embodiments, the CM is a substrate for at least one protease selected from the group consisting of a matrix metalloprotease (MMP), thrombin, a neutrophil elastase, a cysteine protease, legumain, and a serine protease, such as matriptase (MT-SP1), and urokinase (uPA). Without being bound by theory, it is believed that these proteases are up-regulated in at least one of cancer, inflammation, and/or autoimmunity.
• Exemplary substrates include but are not limited to substrates cleavable by one or more of the following enzymes or proteases listed in Table 3.
• In some embodiments, the CM is selected for use with a specific protease, for example a protease that is known to be co-localized with the target of the activatable antibody. For example, the protease is produced by a tumor that is in proximity to T cells that express PD-1. In some embodiments, the protease is produced by a tumor that is co-localized with T cells that express PD-1.
• In some embodiments, the CM is a substrate for at least one MMP. Examples of MMPs include the MMPs listed in the Table 3. In some embodiments, the CM is a substrate for a protease selected from the group consisting of MMP 9, MMP14, MMP1, MMP3, MMP13, MMP17, MMP11, and MMP19. In some embodiments the CM is a substrate for MMP9. In some embodiments, the CM is a substrate for MMP14.
• In some embodiments, the CM is a substrate that includes the sequence TGRGPSWV (SEQ ID NO: 295); SARGPSRW (SEQ ID NO: 319); TARGPSFK (SEQ ID NO: 297); LSGRSDNH (SEQ ID NO: 294); GGWHTGRN (SEQ ID NO: 320); HTGRSGAL (SEQ ID NO: 321); PLTGRSGG (SEQ ID NO: 296); AARGPAIH (SEQ ID NO: 322); RGPAFNPM (SEQ ID NO: 323); SSRGPAYL (SEQ ID NO: 324); RGPATPIM (SEQ ID NO: 325); RGPA (SEQ ID NO: 326); GGQPSGMWGW (SEQ ID NO: 327); FPRPLGITGL (SEQ ID NO: 328); VHMPLGFLGP (SEQ ID NO: 302); SPLTGRSG (SEQ ID NO: 329); SAGFSLPA (SEQ ID NO: 330); LAPLGLQRR (SEQ ID NO: 331); SGGPLGVR (SEQ ID NO: 332); PLGL (SEQ ID NO: 333); LSGRSGNH (SEQ ID NO: 1157); SGRSANPRG (SEQ ID NO: 1158); LSGRSDDH (SEQ ID NO: 1161); LSGRSDIH (SEQ ID NO: 1162); LSGRSDQH (SEQ ID NO: 1165); LSGRSDTH (SEQ ID NO: 1166); LSGRSDDH (SEQ ID NO: 1169); LSGRSDNP (SEQ ID NO: 1520); LSGRSANP (SEQ ID NO: 1695); LSGRSANI (SEQ ID NO: 1696); and/or LSGRSDNI (SEQ ID NO: 1697).
• In some embodiments, the CM comprises the amino acid sequence LSGRSDNH (SEQ ID NO: 294). In some embodiments, the CM comprises the amino acid sequence TGRGPSWV (SEQ ID NO: 295). In some embodiments, the CM comprises the amino acid sequence PLTGRSGG (SEQ ID NO: 296). In some embodiments, the CM comprises the amino acid sequence GGQPSGMWGW (SEQ ID NO: 327). In some embodiments, the CM comprises the amino acid sequence FPRPLGITGL (SEQ ID NO: 328). In some embodiments, the CM comprises the amino acid sequence VHMPLGFLGP (SEQ ID NO: 302). In some embodiments, the CM comprises the amino acid sequence PLGL (SEQ ID NO: 333). In some embodiments, the CM comprises the amino acid sequence SARGPSRW (SEQ ID NO: 319). In some embodiments, the CM comprises the amino acid sequence TARGPSFK (SEQ ID NO: 297). In some embodiments, the CM comprises the amino acid sequence GGWHTGRN (SEQ ID NO: 320). In some embodiments, the CM comprises the amino acid sequence HTGRSGAL (SEQ ID NO: 321). In some embodiments, the CM comprises the amino acid sequence AARGPAIH (SEQ ID NO: 322). In some embodiments, the CM comprises the amino acid sequence RGPAFNPM (SEQ ID NO: 323). In some embodiments, the CM comprises the amino acid sequence SSRGPAYL (SEQ ID NO: 324). In some embodiments, the CM comprises the amino acid sequence RGPATPIM (SEQ ID NO: 325). In some embodiments, the CM comprises the amino acid sequence RGPA (SEQ ID NO: 326). In some embodiments, the CM comprises the amino acid sequence LSGRSGNH (SEQ ID NO: 1157). In some embodiments, the CM comprises the amino acid sequence SGRSANPRG (SEQ ID NO: 1158). In some embodiments, the CM comprises the amino acid sequence LSGRSDDH (SEQ ID NO: 1161). In some embodiments, the CM comprises the amino acid sequence LSGRSDIH (SEQ ID NO: 1162). In some embodiments, the CM comprises the amino acid sequence LSGRSDQH (SEQ ID NO: 1165). In some embodiments, the CM comprises the amino acid sequence LSGRSDTH (SEQ ID NO: 1166). In some embodiments, the CM comprises the amino acid sequence LSGRSDYH (SEQ ID NO: 1169). In some embodiments, the CM comprises the amino acid sequence LSGRSDNP (SEQ ID NO: 1520). In some embodiments, the CM comprises the amino acid sequence LSGRSANP (SEQ ID NO: 1695). In some embodiments, the CM comprises the amino acid sequence LSGRSANI (SEQ ID NO: 1696). In some embodiments, the CM comprises the amino acid sequence LSGRSDNI (SEQ ID NO: 1697).
• In some embodiments, the CM is a substrate for an MMP and includes the sequence ISSGLSS (SEQ ID NO: 334); QNQALRMA (SEQ ID NO: 305); AQNLLGMV (SEQ ID NO: 304); STFPFGMF (SEQ ID NO: 307); PVGYTSSL (SEQ ID NO: 335); DWLYWPGI (SEQ ID NO: 336), ISSGLLSS (SEQ ID NO: 308), LKAAPRWA (SEQ ID NO: 337); GPSHLVLT (SEQ ID NO: 338); LPGGLSPW (SEQ ID NO: 339); MGLFSEAG (SEQ ID NO: 340); SPLPLRVP (SEQ ID NO: 341); RMHLRSLG (SEQ ID NO: 342); LAAPLGLL (SEQ ID NO: 306); AVGLLAPP (SEQ ID NO: 303); LLAPSHRA (SEQ ID NO: 343); PAGLWLDP (SEQ ID NO: 309); MIAPVAYR (SEQ ID NO: 1698); RPSPMWAY (SEQ ID NO: 1699); WATPRPMR (SEQ ID NO: 1700); FRLLDWQW (SEQ ID NO: 1701); ISSGL (SEQ ID NO: 1702); ISSGLLS (SEQ ID NO: 1703); and/or ISSGLL (SEQ ID NO: 1704).
• In some embodiments, the CM comprises the amino acid sequence ISSGLSS (SEQ ID NO: 334). In some embodiments, the CM comprises the amino acid sequence QNQALRMA (SEQ ID NO: 305). In some embodiments, the CM comprises the amino acid sequence AQNLLGMV (SEQ ID NO: 304). In some embodiments, the CM comprises the amino acid sequence STFPFGMF (SEQ ID NO: 307). In some embodiments, the CM comprises the amino acid sequence PVGYTSSL (SEQ ID NO: 335). In some embodiments, the CM comprises the amino acid sequence DWLYWPGI (SEQ ID NO: 336). In some embodiments, the CM comprises the amino acid sequence ISSGLLSS (SEQ ID NO: 308). In some embodiments, the CM comprises the amino acid sequence LKAAPRWA (SEQ ID NO: 337). In some embodiments, the CM comprises the amino acid sequence GPSHLVLT (SEQ ID NO: 338). In some embodiments, the CM comprises the amino acid sequence LPGGLSPW (SEQ ID NO: 339). In some embodiments, the CM comprises the amino acid sequence MGLFSEAG (SEQ ID NO: 340). In some embodiments, the CM comprises the amino acid sequence SPLPLRVP (SEQ ID NO: 341). In some embodiments, the CM comprises the amino acid sequence RMHLRSLG (SEQ ID NO: 342). In some embodiments, the CM comprises the amino acid sequence LAAPLGLL (SEQ ID NO: 306). In some embodiments, the CM comprises the amino acid sequence AVGLLAPP (SEQ ID NO: 303). In some embodiments, the CM comprises the amino acid sequence LLAPSHRA (SEQ ID NO: 343). In some embodiments, the CM comprises the amino acid sequence PAGLWLDP (SEQ ID NO: 309). In some embodiments, the CM comprises the amino acid sequence MIAPVAYR (SEQ ID NO: 1698). In some embodiments, the CM comprises the amino acid sequence RPSPMWAY (SEQ ID NO: 1699). In some embodiments, the CM comprises the amino acid sequence WATPRPMR (SEQ ID NO: 1700). In some embodiments, the CM comprises the amino acid sequence FRLLDWQW (SEQ ID NO: 1701). In some embodiments, the CM comprises the amino acid sequence ISSGL (SEQ ID NO: 1702). In some embodiments, the CM comprises the amino acid sequence ISSGLLS (SEQ ID NO: 1703). In some embodiments, the CM comprises the amino acid sequence ISSGLL (SEQ ID NO: 1704).
• In some embodiments, the CM is a substrate for thrombin. In some embodiments, the CM is a substrate for thrombin and includes the sequence GPRSFGL (SEQ ID NO: 344) or GPRSFG (SEQ ID NO: 345). In some embodiments, the CM comprises the amino acid sequence GPRSFGL (SEQ ID NO: 344). In some embodiments, the CM comprises the amino acid sequence GPRSFG (SEQ ID NO: 345).
• In some embodiments, the CM comprises an amino acid sequence selected from the group consisting of NTLSGRSENHSG (SEQ ID NO: 298); NTLSGRSGNHGS (SEQ ID NO: 299); TSTSGRSANPRG (SEQ ID NO: 300); TSGRSANP (SEQ ID NO: 301); VAGRSMRP (SEQ ID NO: 310); VVPEGRRS (SEQ ID NO: 311); ILPRSPAF (SEQ ID NO: 312); MVLGRSLL (SEQ ID NO: 313); QGRAITFI (SEQ ID NO: 314); SPRSIMLA (SEQ ID NO: 315); and SMLRSMPL (SEQ ID NO: 316).
• In some embodiments, the CM comprises the amino acid sequence NTLSGRSENHSG (SEQ ID NO: 298). In some embodiments, the CM comprises the amino acid sequence NTLSGRSGNHGS (SEQ ID NO: 299). In some embodiments, the CM comprises the amino acid sequence TSTSGRSANPRG (SEQ ID NO: 300). In some embodiments, the CM comprises the amino acid sequence TSGRSANP (SEQ ID NO: 301). In some embodiments, the CM comprises the amino acid sequence VAGRSMRP (SEQ ID NO: 310). In some embodiments, the CM comprises the amino acid sequence VVPEGRRS (SEQ ID NO: 311). In some embodiments, the CM comprises the amino acid sequence ILPRSPAF (SEQ ID NO: 312). In some embodiments, the CM comprises the amino acid sequence MVLGRSLL (SEQ ID NO: 313). In some embodiments, the CM comprises the amino acid sequence QGRAITFI (SEQ ID NO: 314). In some embodiments, the CM comprises the amino acid sequence SPRSIMLA (SEQ ID NO: 315). In some embodiments, the CM comprises the amino acid sequence SMLRSMPL (SEQ ID NO: 316).
• In some embodiments, the CM comprises an amino acid sequence selected from the group consisting of SEQ ID NOs: 214, 294-361, 1092-1112, 1157, 1158, 1161, 1162, 1165, 1166, 1169, 1520, and 1695-1704. In some embodiments, the CM comprises an amino acid sequence selected from the group consisting of SEQ ID NOs: 214, 294, 300, 302, 303, 305, 308, 318, 347, 361, 1092-1102, 1111, and 1157.
• In some embodiments, the CM is a substrate for a neutrophil elastase. In some embodiments, the CM is a substrate for a serine protease. In some embodiments, the CM is a substrate for uPA. In some embodiments, the CM is a substrate for legumain. In some embodiments, the CM is a substrate for matriptase. In some embodiments, the CM is a substrate for a cysteine protease. In some embodiments, the CM is a substrate for a cysteine protease, such as a cathepsin.
• In some embodiments, the CM is a CM1-CM2 substrate and includes the sequence ISSGLLSGRSDNH (SEQ ID NO: 214); ISSGLLSSGGSGGSLSGRSDNH (SEQ ID NO: 346); AVGLLAPPGGTSTSGRSANPRG (SEQ ID NO: 347); TSTSGRSANPRGGGAVGLLAPP (SEQ ID NO: 348); VHMPLGFLGPGGTSTSGRSANPRG (SEQ ID NO: 349); TSTSGRSANPRGGGVHMPLGFLGP (SEQ ID NO: 350); AVGLLAPPGGLSGRSDNH (SEQ ID NO: 318); LSGRSDNHGGAVGLLAPP (SEQ ID NO: 351); VHMPLGFLGPGGLSGRSDNH (SEQ ID NO: 352); LSGRSDNHGGVHMPLGFLGP (SEQ ID NO: 353); LSGRSDNHGGSGGSISSGLLSS (SEQ ID NO: 354); LSGRSGNHGGSGGSISSGLLSS (SEQ ID NO: 355); ISSGLLSSGGSGGSLSGRSGNH (SEQ ID NO: 356); LSGRSDNHGGSGGSQNQALRMA (SEQ ID NO: 357); QNQALRMAGGSGGSLSGRSDNH (SEQ ID NO: 358); LSGRSGNHGGSGGSQNQALRMA (SEQ ID NO: 359); QNQALRMAGGSGGSLSGRSGNH (SEQ ID NO: 360); ISSGLLSGRSGNH (SEQ ID NO: 361); ISSGLLSGRSANPRG (SEQ ID NO: 1092); AVGLLAPPTSGRSANPRG (SEQ ID NO: 1093); AVGLLAPPSGRSANPRG (SEQ ID NO: 1094); ISSGLLSGRSDDH (SEQ ID NO: 1095); ISSGLLSGRSDIH (SEQ ID NO: 1096); ISSGLLSGRSDQH (SEQ ID NO: 1097); ISSGLLSGRSDTH (SEQ ID NO: 1098); ISSGLLSGRSDDH (SEQ ID NO: 1099); ISSGLLSGRSDNP (SEQ ID NO: 1100); ISSGLLSGRSANP (SEQ ID NO: 1101); ISSGLLSGRSANI (SEQ ID NO: 1102); AVGLLAPPGGLSGRSDDH (SEQ ID NO: 1103); AVGLLAPPGGLSGRSDIH (SEQ ID NO: 1104); AVGLLAPPGGLSGRSDQH (SEQ ID NO: 1105); AVGLLAPPGGLSGRSDTH (SEQ ID NO: 1106); AVGLLAPPGGLSGRSDDH (SEQ ID NO: 1107); AVGLLAPPGGLSGRSDNP (SEQ ID NO: 1108); AVGLLAPPGGLSGRSANP (SEQ ID NO: 1109); AVGLLAPPGGLSGRSANI (SEQ ID NO: 1110); ISSGLLSGRSDNI (SEQ ID NO: 1111); and/or AVGLLAPPGGLSGRSDNI (SEQ ID NO: 1112).
• In some embodiments, the CM1-CM2 substrate includes the sequence ISSGLLSGRSDNH (SEQ ID NO: 214), which is also referred to herein as substrate 2001. In some embodiments, the CM1-CM2 substrate includes the sequence ISSGLLSSGGSGGSLSGRSDNH (SEQ ID NO: 346), which is also referred to herein as substrate 1001/LP′/0001, where LP′ as used in this CM1-CM2 substrate is the amino acid sequence GGSGGS (SEQ ID NO: 1519). In some embodiments, the CM1-CM2 substrate includes the sequence AVGLLAPPGGTSTSGRSANPRG (SEQ ID NO: 347), which is also referred to herein as substrate 1004/LP′/0003, where LP′ as used in this CM1-CM2 substrate is the amino acid sequence GG. In some embodiments, the CM1-CM2 substrate includes the sequence TSTSGRSANPRGGGAVGLLAPP (SEQ ID NO: 348), which is also referred to herein as substrate 0003/LP′/1004, where LP′ as used in this CM1-CM2 substrate is the amino acid sequence GG. In some embodiments, the CM1-CM2 substrate includes the sequence VHMPLGFLGPGGTSTSGRSANPRG (SEQ ID NO: 349), which is also referred to herein as substrate 1003/LP′/0003, where LP′ as used in this CM1-CM2 substrate is the amino acid sequence GG. In some embodiments, the CM1-CM2 substrate includes the sequence TSTSGRSANPRGGGVHMPLGFLGP (SEQ ID NO: 350), which is also referred to herein as substrate 0003/LP′/1003, where LP′ as used in this CM1-CM2 substrate is the amino acid sequence GG. In some embodiments, the CM1-CM2 substrate includes the sequence AVGLLAPPGGLSGRSDNH (SEQ ID NO: 318), which is also referred to herein as substrate 1004/LP′/0001, where LP′ as used in this CM1-CM2 substrate is the amino acid sequence GG. In some embodiments, the CM1-CM2 substrate includes the sequence LSGRSDNHGGAVGLLAPP (SEQ ID NO: 351), which is also referred to herein as substrate 0001/LP′/1004, where LP′ as used in this CM1-CM2 substrate is the amino acid sequence GG. In some embodiments, the CM1-CM2 substrate includes the sequence VHMPLGFLGPGGLSGRSDNH (SEQ ID NO: 352), which is also referred to herein as substrate 1003/LP′/0001, where LP′ as used in this CM1-CM2 substrate is the amino acid sequence GG. In some embodiments, the CM1-CM2 substrate includes the sequence LSGRSDNHGGVHMPLGFLGP (SEQ ID NO: 353), which is also referred to herein as substrate 0001/LP′/1003, where LP′ as used in this CM1-CM2 substrate is the amino acid sequence GG. In some embodiments, the CM1-CM2 substrate includes the sequence LSGRSDNHGGSGGSISSGLLSS (SEQ ID NO: 354), which is also referred to herein as substrate 0001/LP′/1001, where LP′ as used in this CM1-CM2 substrate is the amino acid sequence GGSGGS (SEQ ID NO: 1519). In some embodiments, the CM1-CM2 substrate includes the sequence LSGRSGNHGGSGGSISSGLLSS (SEQ ID NO: 355), which is also referred to herein as substrate 0002/LP′/1001, where LP′ as used in this CM1-CM2 substrate is the amino acid sequence GGSGGS (SEQ ID NO: 1519). In some embodiments, the CM1-CM2 substrate includes the sequence ISSGLLSSGGSGGSLSGRSGNH (SEQ ID NO: 356), which is also referred to herein as substrate 1001/LP′/0002, where LP′ as used in this CM1-CM2 substrate is the amino acid sequence GGSGGS (SEQ ID NO: 1519). In some embodiments, the CM1-CM2 substrate includes the sequence LSGRSDNHGGSGGSQNQALRMA (SEQ ID NO: 357), which is also referred to herein as substrate 0001/LP′/1002, where LP′ as used in this CM1-CM2 substrate is the amino acid sequence GGSGGS (SEQ ID NO: 1519). In some embodiments, the CM1-CM2 substrate includes the sequence QNQALRMAGGSGGSLSGRSDNH (SEQ ID NO: 358), which is also referred to herein as substrate 1002/LP′/0001, where LP′ as used in this CM1-CM2 substrate is the amino acid sequence GGSGGS (SEQ ID NO: 1519). In some embodiments, the CM1-CM2 substrate includes the sequence LSGRSGNHGGSGGSQNQALRMA (SEQ ID NO: 359), which is also referred to herein as substrate 0002/LP′/1002, where LP′ as used in this CM1-CM2 substrate is the amino acid sequence GGSGGS (SEQ ID NO: 1519). In some embodiments, the CM1-CM2 substrate includes the sequence QNQALRMAGGSGGSLSGRSGNH (SEQ ID NO: 360), which is also referred to herein as substrate 1002/LP′/0002, where LP′ as used in this CM1-CM2 substrate is the amino acid sequence GGSGGS (SEQ ID NO: 1519). In some embodiments, the CM1-CM2 substrate includes the sequence ISSGLLSGRSGNH (SEQ ID NO: 361), which is also referred to herein as substrate 2002. In some embodiments, the CM1-CM2 substrate includes the sequence ISSGLLSGRSANPRG (SEQ ID NO: 1092), which is also referred to herein as substrate 2003. In some embodiments, the CM1-CM2 substrate includes the sequence AVGLLAPPTSGRSANPRG (SEQ ID NO: 1093), which is also referred to herein as substrate 2004. In some embodiments, the CM1-CM2 substrate includes the sequence AVGLLAPPSGRSANPRG (SEQ ID NO: 1094), which is also referred to herein as substrate 2005. In some embodiments, the CM1-CM2 substrate includes the sequence ISSGLLSGRSDDH (SEQ ID NO: 1095), which is also referred to herein as substrate 2006. In some embodiments, the CM1-CM2 substrate includes the sequence ISSGLLSGRSDIH (SEQ ID NO: 1096), which is also referred to herein as substrate 2007. In some embodiments, the CM1-CM2 substrate includes the sequence ISSGLLSGRSDQH (SEQ ID NO: 1097), which is also referred to herein as substrate 2008. In some embodiments, the CM1-CM2 substrate includes the sequence ISSGLLSGRSDTH (SEQ ID NO: 1098), which is also referred to herein as substrate 2009. In some embodiments, the CM1-CM2 substrate includes the sequence ISSGLLSGRSDDH (SEQ ID NO: 1099), which is also referred to herein as substrate 2010. In some embodiments, the CM1-CM2 substrate includes the sequence ISSGLLSGRSDNP (SEQ ID NO: 1100), which is also referred to herein as substrate 2011. In some embodiments, the CM1-CM2 substrate includes the sequence ISSGLLSGRSANP (SEQ ID NO: 1101), which is also referred to herein as substrate 2012. In some embodiments, the CM1-CM2 substrate includes the sequence ISSGLLSGRSANI (SEQ ID NO: 1102), which is also referred to herein as substrate 2013. In some embodiments, the CM1-CM2 substrate includes the sequence AVGLLAPPGGLSGRSDDH (SEQ ID NO: 1103), which is also referred to herein as substrate 3006. In some embodiments, the CM1-CM2 substrate includes the sequence AVGLLAPPGGLSGRSDIH (SEQ ID NO: 1104), which is also referred to herein as substrate 3007. In some embodiments, the CM1-CM2 substrate includes the sequence AVGLLAPPGGLSGRSDQH (SEQ ID NO: 1105), which is also referred to herein as substrate 3008. In some embodiments, the CM1-CM2 substrate includes the sequence AVGLLAPPGGLSGRSDTH (SEQ ID NO: 1106), which is also referred to herein as substrate 3009. In some embodiments, the CM1-CM2 substrate includes the sequence AVGLLAPPGGLSGRSDDH (SEQ ID NO: 1107), which is also referred to herein as substrate 3010. In some embodiments, the CM1-CM2 substrate includes the sequence AVGLLAPPGGLSGRSDNP (SEQ ID NO: 1108), which is also referred to herein as substrate 3011. In some embodiments, the CM1-CM2 substrate includes the sequence AVGLLAPPGGLSGRSANP (SEQ ID NO: 1109), which is also referred to herein as substrate 3012. In some embodiments, the CM1-CM2 substrate includes the sequence AVGLLAPPGGLSGRSANI (SEQ ID NO: 1110), which is also referred to herein as substrate 3013. In some embodiments, the CM1-CM2 substrate includes the sequence ISSGLLSGRSDNI (SEQ ID NO: 1111), which is also referred to herein as substrate 2014. In some embodiments, the CM1-CM2 substrate includes the sequence and/or AVGLLAPPGGLSGRSDNI (SEQ ID NO: 1112), which is also referred to herein as substrate 3014. In some embodiments, the CM1-CM2 substrate includes the sequence GLSGRSDNHGGAVGLLAPP (SEQ ID NO: 1970), which is also referred to herein as substrate 0001/LP′/1004, where LP′ as used in this CM1-CM2 substrate is the amino acid sequence GG. In some embodiments, the CM1-CM2 substrate includes the sequence GLSGRSDNHGGVHMPLGFLGP (SEQ ID NO: 1971), which is also referred to herein as substrate 0001/LP′/1003, where LP′ as used in this CM1-CM2 substrate is the amino acid sequence GG.
• In some embodiments, the CM is a substrate for at least two proteases. In some embodiments, each protease is selected from the group consisting of those shown in Table 3. In some embodiments, the CM is a substrate for at least two proteases, wherein one of the proteases is selected from the group consisting of a MMP, thrombin, a neutrophil elastase, a cysteine protease, uPA, legumain and matriptase and the other protease is selected from the group consisting of those shown in Table 3. In some embodiments, the CM is a substrate for at least two proteases selected from the group consisting of a MMP, thrombin, a neutrophil elastase, a cysteine protease, uPA, legumain and matriptase.
• In some embodiments, the activatable antibody includes at least a first CM and a second CM. In some embodiments, the first CM and the second CM are each polypeptides of no more than 15 amino acids long. In some embodiments, the first CM and the second CM in the activatable antibody in the uncleaved state have the structural arrangement from N-terminus to C-terminus as follows: MM-CM1-CM2-AB or AB-CM2-CM1-MM. In some embodiments, at least one of the first CM and the second CM is a polypeptide that functions as a substrate for a protease selected from the group consisting of a MMP, thrombin, a neutrophil elastase, a cysteine protease, uPA, legumain, and matriptase. In some embodiments, the first CM is cleaved by a first cleaving agent selected from the group consisting of a MMP, thrombin, a neutrophil elastase, a cysteine protease, uPA, legumain, and matriptase in a target tissue and the second CM is cleaved by a second cleaving agent in a target tissue. In some embodiments, the other protease is selected from the group consisting of those shown in Table 3. In some embodiments, the first cleaving agent and the second cleaving agent are the same protease selected from the group consisting of a MMP, thrombin, a neutrophil elastase, a cysteine protease, uPA, legumain, and matriptase, and the first CM and the second CM are different substrates for the enzyme. In some embodiments, the first cleaving agent and the second cleaving agent are the same protease selected from the group consisting of those shown in Table 3. In some embodiments, the first cleaving agent and the second cleaving agent are different proteases. In some embodiments, the first cleaving agent and the second cleaving agent are co-localized in the target tissue. In some embodiments, the first CM and the second CM are cleaved by at least one cleaving agent in the target tissue.
• In some embodiments, the activatable antibody is exposed to and cleaved by a protease such that, in the activated or cleaved state, the activated antibody includes a light chain amino acid sequence that includes at least a portion of LP2 and/or CM sequence after the protease has cleaved the CM.
• In some embodiments, the activatable antibody also includes an agent conjugated to the AB. In some embodiments, the agent conjugated to the AB or the AB of an activatable antibody is a therapeutic agent. In some embodiments, the agent is conjugated to the AB via a cleavable linker. In some embodiments, the agent is conjugated to the AB via a linker that includes at least one CM1-CM2 substrate sequence. In some embodiments, the agent is conjugated to the AB via a noncleavable linker.
• In some embodiments, the agent is an anti-inflammatory agent.
• In some embodiments, the activatable antibody also includes a detectable moiety. In some embodiments, the detectable moiety is a diagnostic agent.
• In some embodiments, the activatable antibody also includes a signal peptide. In some embodiments, the signal peptide is conjugated to the activatable antibody via a spacer. In some embodiments, the spacer is conjugated to the activatable antibody in the absence of a signal peptide. In some embodiments, the spacer is joined directly to the MM of the activatable antibody. In some embodiments, the spacer is joined directly to the MM of the activatable antibody in the structural arrangement from N-terminus to C-terminus of spacer-MM-CM-AB. An example of a spacer joined directly to the N-terminus of MM of the activatable antibody is selected from the group consisting of QGQSGQG (SEQ ID NO: 362), QGQSGQ (SEQ ID NO: 913), QGQSG (SEQ ID NO: 914), QGQS (SEQ ID NO: 915), QGQ (SEQ ID NO: 916), QG (SEQ ID NO: 917), and Q. Additional examples of spacers include GQSGQG (SEQ ID NO: 2042), QSGQG (SEQ ID NO: 2043), SGQG (SEQ ID NO: 2044), GQG(SEQ ID NO: 2045), QG(SEQ ID NO: 2046), and G. In some embodiments, the spacer includes at least the amino acid sequence QGQSGQG (SEQ ID NO: 362). In some embodiments, the spacer includes at least the amino acid sequence QGQSGQ (SEQ ID NO: 913). In some embodiments, the spacer includes at least the amino acid sequence QGQSG (SEQ ID NO: 914). In some embodiments, the spacer includes at least the amino acid sequence QGQS (SEQ ID NO: 915), In some embodiments, the spacer includes at least the amino acid sequence QGQ (SEQ ID NO: 916). In some embodiments, the spacer includes at least the amino acid sequence QG (SEQ ID NO: 917). In some embodiments, the spacer includes at least the amino acid residue Q. In some embodiments, the spacer includes at least the amino acid sequence GQSGQG (SEQ ID NO: 2042). In some embodiments, the spacer includes at least the amino acid sequence QSGQG (SEQ ID NO: 2043). In some embodiments, the spacer includes at least the amino acid sequence SGQG (SEQ ID NO: 2044). In some embodiments, the spacer includes at least the amino acid sequence GQG(SEQ ID NO: 2045). In some embodiments, the spacer includes at least the amino acid sequence QG (SEQ ID NO: 2046). In some embodiments, the spacer includes at least the amino acid sequence G. In some embodiments, the activatable antibody does not include a spacer sequence.
• In some embodiments, the AB of the activatable antibody naturally contains one or more disulfide bonds. In some embodiments, the AB can be engineered to include one or more disulfide bonds.
• In some embodiments, the serum half-life of the activatable antibody is longer than that of the corresponding antibody; e.g., the pK of the activatable antibody is longer than that of the corresponding antibody. In some embodiments, the serum half-life of the activatable antibody is similar to that of the corresponding antibody. In some embodiments, the serum half-life of the activatable antibody is at least 15 days when administered to an organism. In some embodiments, the serum half-life of the activatable antibody is at least 12 days when administered to an organism. In some embodiments, the serum half-life of the activatable antibody is at least 11 days when administered to an organism. In some embodiments, the serum half-life of the activatable antibody is at least 10 days when administered to an organism. In some embodiments, the serum half-life of the activatable antibody is at least 9 days when administered to an organism. In some embodiments, the serum half-life of the activatable antibody is at least 8 days when administered to an organism. In some embodiments, the serum half-life of the activatable antibody is at least 7 days when administered to an organism. In some embodiments, the serum half-life of the activatable antibody is at least 6 days when administered to an organism. In some embodiments, the serum half-life of the activatable antibody is at least 5 days when administered to an organism. In some embodiments, the serum half-life of the activatable antibody is at least 4 days when administered to an organism. In some embodiments, the serum half-life of the activatable antibody is at least 3 days when administered to an organism. In some embodiments, the serum half-life of the activatable antibody is at least 2 days when administered to an organism. In some embodiments, the serum half-life of the activatable antibody is at least 24 hours when administered to an organism. In some embodiments, the serum half-life of the activatable antibody is at least 20 hours when administered to an organism. In some embodiments, the serum half-life of the activatable antibody is at least 18 hours when administered to an organism. In some embodiments, the serum half-life of the activatable antibody is at least 16 hours when administered to an organism. In some embodiments, the serum half-life of the activatable antibody is at least 14 hours when administered to an organism. In some embodiments, the serum half-life of the activatable antibody is at least 12 hours when administered to an organism. In some embodiments, the serum half-life of the activatable antibody is at least 10 hours when administered to an organism. In some embodiments, the serum half-life of the activatable antibody is at least 8 hours when administered to an organism. In some embodiments, the serum half-life of the activatable antibody is at least 6 hours when administered to an organism. In some embodiments, the serum half-life of the activatable antibody is at least 4 hours when administered to an organism. In some embodiments, the serum half-life of the activatable antibody is at least 3 hours when administered to an organism.
• In some embodiments, the activatable anti-PD-1 antibody is monospecific.
• In some embodiments, the activatable anti-PD-1 antibody is multispecific, e.g., by way of non-limiting example, bispecific or trifunctional. In some embodiments, the activatable anti-PD-1 antibody is formulated as part of a pro-Bispecific T Cell Engager (BITE) molecule, i.e., the BITE includes a masking moiety and a cleavable moiety. In some embodiments, the activatable anti-PD-1 antibody is formulated as part of a pro-Chimeric Antigen Receptor (CAR) modified T cell, modified NK cell, or other modified immune effector cell. In some embodiments, an activatable anti-PD-1 antibody is formulated as part of another engineered receptor on an immune effector cell; i.e., the pro-CAR or other pro-engineered receptor includes a masking moiety and a cleavable moiety.
• In some embodiments, the activatable antibody or antigen-binding fragment thereof is incorporated in a multispecific activatable antibody or antigen-binding fragment thereof, where at least one arm of the multispecific activatable antibody specifically binds PD-1. In some embodiments, the activatable antibody or antigen-binding fragment thereof is incorporated in a bispecific activatable antibody or antigen-binding fragment thereof, where at least one arm of the bispecific activatable antibody specifically binds PD-1.
• In some embodiments, at least one arm of the multispecific activatable antibody, e.g., a bispecific activatable antibody, comprises a heavy chain amino acid sequence selected from the group consisting of SEQ ID NO: 1, 5, 9, 13, 17, 21, 23, 25, 27, 29, 31, 33, 35, and 37. In some embodiments, at least one arm of the multispecific activatable antibody, e.g., a bispecific activatable antibody, comprises a heavy chain amino acid sequence selected from the group consisting of SEQ ID NO: 21, 23, 25, 27, 29, 31, 33, 35, and 37.
• In some embodiments, at least one arm of the multispecific activatable antibody, e.g., a bispecific activatable antibody, comprises a light chain amino acid sequence selected from the group consisting of SEQ ID NO: 3, 7, 11, 15, 19, 39, 41, 43, 45, 47, 49, 51, 53, 55, 57, and 59. In some embodiments, at least one arm of the multispecific activatable antibody, e.g., a bispecific activatable antibody, comprises a light chain amino acid sequence selected from the group consisting of SEQ ID NO: 39, 41, 43, 45, 47, 49, 51, 53, 55, 57, and 59.
• In some embodiments, at least one arm of the multispecific activatable antibody, e.g., a bispecific activatable antibody, a heavy chain amino acid sequence comprising an amino acid sequence selected from the group consisting of SEQ ID NO: 1, 5, 9, 13, 17, 21, 23, 25, 27, 29, 31, 33, 35, and 37, and a light chain amino acid sequence selected from the group consisting of SEQ ID NO: 3, 7, 11, 15, 19, 39, 41, 43, 45, 47, 49, 51, 53, 55, 57, and 59. In some embodiments, at least one arm of the multispecific activatable antibody, e.g., a bispecific activatable antibody, a heavy chain amino acid sequence comprising an amino acid sequence selected from the group consisting of SEQ ID NO: 21, 23, 25, 27, 29, 31, 33, 35, and 37, and a light chain amino acid sequence selected from the group consisting of SEQ ID NO: 39, 41, 43, 45, 47, 49, 51, 53, 55, 57, and 59. In some embodiments, at least one arm of the multispecific activatable antibody, e.g., a bispecific activatable antibody, includes a heavy chain that comprises or is derived from amino acid sequence SEQ ID NO: 21. In some embodiments, at least one arm of the multispecific activatable antibody, e.g., a bispecific activatable antibody, includes a light chain that comprises or is derived from amino acid sequence SEQ ID NO: 45 or SEQ ID NO: 47. In some embodiments, at least one arm of the multispecific activatable antibody, e.g., a bispecific activatable antibody, includes a heavy chain that comprises or is derived from amino acid sequence SEQ ID NO: 21 and a light chain that comprises or is derived from amino acid sequence SEQ ID NO: 45 or SEQ ID NO: 47. In some embodiments, at least one arm of the multispecific activatable antibody, e.g., a bispecific activatable antibody, includes a heavy chain that comprises or is derived from amino acid sequence SEQ ID NO: 21 and a light chain that comprises or is derived from amino acid sequence SEQ ID NO: 45. In some embodiments, at least one arm of the multispecific activatable antibody, e.g., a bispecific activatable antibody, includes a heavy chain that comprises or is derived from amino acid sequence SEQ ID NO: 21 and a light chain that comprises or is derived from amino acid sequence SEQ ID NO: 47.
• In some embodiments, at least one arm of the multispecific activatable antibody, e.g., a bispecific activatable antibody, includes the combination of the complementarity determining region (CDR) sequences of the heavy chain amino acid sequence of SEQ ID NO: 21. In some embodiments, at least one arm of the multispecific activatable antibody, e.g., a bispecific activatable antibody, includes the combination of the CDR sequences of the light chain amino acid sequence of SEQ ID NO: 45 or of SEQ ID NO: 47. In some embodiments, at least one arm of the multispecific activatable antibody, e.g., a bispecific activatable antibody, includes a combination of the CDR sequences of the heavy chain amino acid sequence of SEQ ID NO: 21, and the CDR sequences of the light chain amino acid sequence of SEQ ID NO: 45 or 47. In some embodiments, at least one arm of the multispecific activatable antibody, e.g., a bispecific activatable antibody, includes a combination of the CDR sequences of the heavy chain amino acid sequence of SEQ ID NO: 21, and the CDR sequences of the light chain amino acid sequence of SEQ ID NO: 45. In some embodiments, at least one arm of the multispecific activatable antibody, e.g., a bispecific activatable antibody, includes a combination of the CDR sequences of the heavy chain amino acid sequence of SEQ ID NO: 21, and the CDR sequences of the light chain amino acid sequence of SEQ ID NO: 47.
• In some embodiments, at least one arm of the multispecific activatable antibody, e.g., a bispecific activatable antibody includes: (a) a variable heavy chain complementarity determining region 1 (VH CDR1) comprising an amino acid sequence selected from the group consisting of SEQ ID NOs: 653-657; (b) a variable heavy chain complementarity determining region 2 (VH CDR2) comprising an amino acid sequence selected from the group consisting of SEQ ID NOs: 658-663; (c) a variable heavy chain complementarity determining region 3 (VH CDR3) comprising an amino acid sequence selected from the group consisting of SEQ ID NOs: 664-668; (d) a variable light chain complementarity determining region 1 (VL CDR1) comprising an amino acid sequence selected from the group consisting of SEQ ID NOs: 669-677; (e) a variable light chain complementarity determining region 2 (VL CDR2) comprising an amino acid sequence selected from the group consisting of SEQ ID NOs: 678-682; and (f) variable light chain complementarity determining region 3 (VL CDR3) comprising an amino acid sequence selected from the group consisting of SEQ ID NOs: 683-687
• In some embodiments, at least one arm of the multispecific activatable antibody, e.g., a bispecific activatable antibody, includes a combination of a variable heavy chain complementarity determining region 1 (VH CDR1, also referred to herein as CDRH1) sequence, a variable heavy chain complementarity determining region 2 (VH CDR2, also referred to herein as CDRH2) sequence, and a variable heavy chain complementarity determining region 3 (VH CDR3, also referred to herein as CDRH3) sequence, wherein the VH CDR1 sequence comprises GFTFSGYAMS (SEQ ID NO: 653); the VH CDR2 sequence comprises YISNSGGNAH (SEQ ID NO: 658); and the VH CDR3 sequence comprises EDYGTSPFVY (SEQ ID NO: 664).
• In some embodiments, at least one arm of the multispecific activatable antibody, e.g., a bispecific activatable antibody, includes a combination of a variable light chain complementarity determining region 1 (VL CDR1, also referred to herein as CDRL1) sequence, a variable light chain complementarity determining region 2 (VL CDR2, also referred to herein as CDRL2) sequence, and a variable light chain complementarity determining region 3 (VL CDR3, also referred to herein as CDRL3) sequence, wherein the VL CDR1 sequence comprises RASESVDSYGISFMN (SEQ ID NO: 675) or RASESVDAYGISFMN (SEQ ID NO:676); the VL CDR2 sequence comprises AASNQGS (SEQ ID NO: 678); and the VL CDR3 sequence comprises QQSKDVPWT (SEQ ID NO: 683). In some embodiments, at least one arm of the multispecific activatable antibody, e.g., a bispecific activatable antibody, includes a combination of a VL CDR1 sequence, a VL CDR2 sequence, and a VL CDR3 sequence, wherein the VL CDR1 sequence comprises RASESVDSYGISFMN (SEQ ID NO: 675); the VL CDR2 sequence comprises AASNQGS (SEQ ID NO: 678); and the VL CDR3 sequence comprises QQSKDVPWT (SEQ ID NO: 683). In some embodiments, at least one arm of the multispecific activatable antibody, e.g., a bispecific activatable antibody, includes a combination of a VL CDR1 sequence, a VL CDR2 sequence, and a VL CDR3 sequence, wherein the VL CDR1 sequence comprises RASESVDAYGISFMN (SEQ ID NO:676); the VL CDR2 sequence comprises AASNQGS (SEQ ID NO: 678); and the VL CDR3 sequence comprises QQSKDVPWT (SEQ ID NO: 683).
• In some embodiments, at least one arm of the multispecific activatable antibody, e.g., a bispecific activatable antibody, includes a combination of a VH CDR1 sequence, a VH CDR2 sequence, a VH CDR3 sequence, a VL CDR1 sequence, a VL CDR2 sequence, and a VL CDR3 sequence, wherein the VH CDR1 sequence comprises GFTFSGYAMS (SEQ ID NO: 653); the VH CDR2 sequence comprises YISNSGGNAH (SEQ ID NO: 658); and the VH CDR3 sequence comprises EDYGTSPFVY (SEQ ID NO: 664); the VL CDR1 sequence comprises RASESVDSYGISFMN (SEQ ID NO: 675) or RASESVDAYGISFMN (SEQ ID NO:676); the VL CDR2 sequence comprises AASNQGS (SEQ ID NO: 678); and the VL CDR3 sequence comprises QQSKDVPWT (SEQ ID NO: 683). In some embodiments, at least one arm of the multispecific activatable antibody, e.g., a bispecific activatable antibody, includes a combination of a VH CDR1 sequence, a VH CDR2 sequence, a VH CDR3 sequence, a VL CDR1 sequence, a VL CDR2 sequence, and a VL CDR3 sequence, wherein the VH CDR1 sequence comprises GFTFSGYAMS (SEQ ID NO: 653); the VH CDR2 sequence comprises YISNSGGNAH (SEQ ID NO: 658); and the VH CDR3 sequence comprises EDYGTSPFVY (SEQ ID NO: 664); the VL CDR1 sequence comprises RASESVDSYGISFMN (SEQ ID NO: 675); the VL CDR2 sequence comprises AASNQGS (SEQ ID NO: 678); and the VL CDR3 sequence comprises QQSKDVPWT (SEQ ID NO: 683). In some embodiments, at least one arm of the multispecific activatable antibody, e.g., a bispecific activatable antibody, includes a combination of a VH CDR1 sequence, a VH CDR2 sequence, a VH CDR3 sequence, a VL CDR1 sequence, a VL CDR2 sequence, and a VL CDR3 sequence, wherein the VH CDR1 sequence comprises GFTFSGYAMS (SEQ ID NO: 653); the VH CDR2 sequence comprises YISNSGGNAH (SEQ ID NO: 658); and the VH CDR3 sequence comprises EDYGTSPFVY (SEQ ID NO: 664); the VL CDR1 sequence comprises RASESVDAYGISFMN (SEQ ID NO:676); the VL CDR2 sequence comprises AASNQGS (SEQ ID NO: 678); and the VL CDR3 sequence comprises QQSKDVPWT (SEQ ID NO: 683).
• In some embodiments, at least one arm of the multispecific activatable antibody, e.g., a bispecific activatable antibody, includes a heavy chain that comprises or is derived from the amino acid sequence of SEQ ID NO: 1346, and a light chain that comprises or is derived from the amino acid sequence of SEQ ID NO: 626.
• In some embodiments, at least one arm of the multispecific activatable antibody, e.g., a bispecific activatable antibody, includes a heavy chain that comprises or is derived from the amino acid sequence of SEQ ID NO: 1514, and a light chain that comprises or is derived from the amino acid sequence of SEQ ID NO: 638.
• In some embodiments, at least one arm of the multispecific activatable antibody, e.g., a bispecific activatable antibody, includes the combination of the complementarity determining region (CDR) sequences of the heavy chain amino acid sequence of SEQ ID NO: 1346. In some embodiments, at least one arm of the multispecific activatable antibody, e.g., a bispecific activatable antibody, includes the combination of the CDR sequences of the light chain amino acid sequence of SEQ ID NO: 626. In some embodiments, at least one arm of the multispecific activatable antibody, e.g., a bispecific activatable antibody, includes a combination of the CDR sequences of the heavy chain amino acid sequence of SEQ ID NO: 1346, and the CDR sequences of the light chain amino acid sequence of SEQ ID NO: 626.
• In some embodiments, at least one arm of the multispecific activatable antibody, e.g., a bispecific activatable antibody, includes a combination of a variable heavy chain complementarity determining region 1 (VH CDR1, also referred to herein as CDRH1) sequence, a variable heavy chain complementarity determining region 2 (VH CDR2, also referred to herein as CDRH2) sequence, and a variable heavy chain complementarity determining region 3 (VH CDR3, also referred to herein as CDRH3) sequence, wherein the VH CDR1 sequence comprises GITFSNSG (SEQ ID NO: 1705); the VH CDR2 sequence comprises IWYDGSKR (SEQ ID NO: 1706); and the VH CDR3 sequence comprises TNDDY (SEQ ID NO: 1707).
• In some embodiments, at least one arm of the multispecific activatable antibody, e.g., a bispecific activatable antibody, includes a combination of a variable light chain complementarity determining region 1 (VL CDR1, also referred to herein as CDRL1) sequence, a variable light chain complementarity determining region 2 (VL CDR2, also referred to herein as CDRL2) sequence, and a variable light chain complementarity determining region 3 (VL CDR3, also referred to herein as CDRL3) sequence, wherein the VL CDR1 sequence comprises QSVSSY (SEQ ID NO: 1708); the VL CDR2 sequence comprises DAS (SEQ ID NO: 1709); and the VL CDR3 sequence comprises QQSSNWPRT (SEQ ID NO: 1710).
• In some embodiments, at least one arm of the multispecific activatable antibody, e.g., a bispecific activatable antibody, includes a combination of a VH CDR1 sequence, a VH CDR2 sequence, a VH CDR3 sequence, a VL CDR1 sequence, a VL CDR2 sequence, and a VL CDR3 sequence, wherein the VH CDR1 sequence comprises GITFSNSG (SEQ ID NO: 1705); the VH CDR2 sequence comprises IWYDGSKR (SEQ ID NO: 1706); the VH CDR3 sequence comprises TNDDY (SEQ ID NO: 1707); the VL CDR1 sequence comprises QSVSSY (SEQ ID NO: 1708); the VL CDR2 sequence comprises DAS (SEQ ID NO: 1709); and the VL CDR3 sequence comprises QQSSNWPRT (SEQ ID NO: 1710).
• In some embodiments, at least one arm of the multispecific activatable antibody, e.g., a bispecific activatable antibody, includes the combination of the complementarity determining region (CDR) sequences of the heavy chain amino acid sequence of SEQ ID NO: 1514. In some embodiments, at least one arm of the multispecific activatable antibody, e.g., a bispecific activatable antibody, includes the combination of the CDR sequences of the light chain amino acid sequence of SEQ ID NO: 638. In some embodiments, at least one arm of the multispecific activatable antibody, e.g., a bispecific activatable antibody, includes a combination of the CDR sequences of the heavy chain amino acid sequence of SEQ ID NO: 1514, and the CDR sequences of the light chain amino acid sequence of SEQ ID NO: 638.
• In some embodiments, at least one arm of the multispecific activatable antibody, e.g., a bispecific activatable antibody, includes a combination of a variable heavy chain complementarity determining region 1 (VH CDR1, also referred to herein as CDRH1) sequence, a variable heavy chain complementarity determining region 2 (VH CDR2, also referred to herein as CDRH2) sequence, and a variable heavy chain complementarity determining region 3 (VH CDR3, also referred to herein as CDRH3) sequence, wherein the VH CDR1 sequence comprises GYTFTNYY (SEQ ID NO: 1711); the VH CDR2 sequence comprises INPSNGGT (SEQ ID NO: 1712); and the VH CDR3 sequence comprises RRDYRFDMGFDY (SEQ ID NO: 1713).
• In some embodiments, at least one arm of the multispecific activatable antibody, e.g., a bispecific activatable antibody, includes a combination of a variable light chain complementarity determining region 1 (VL CDR1, also referred to herein as CDRL1) sequence, a variable light chain complementarity determining region 2 (VL CDR2, also referred to herein as CDRL2) sequence, and a variable light chain complementarity determining region 3 (VL CDR3, also referred to herein as CDRL3) sequence, wherein the VL CDR1 sequence comprises KGVSTSGYSY (SEQ ID NO: 1714); the VL CDR2 sequence comprises LAS (SEQ ID NO: 1715); and the VL CDR3 sequence comprises QHSRDLPLT (SEQ ID NO: 1716).
• In some embodiments, at least one arm of the multispecific activatable antibody, e.g., a bispecific activatable antibody, includes a combination of a VH CDR1 sequence, a VH CDR2 sequence, a VH CDR3 sequence, a VL CDR1 sequence, a VL CDR2 sequence, and a VL CDR3 sequence, wherein the VH CDR1 sequence comprises GYTFTNYY (SEQ ID NO: 1711); the VH CDR2 sequence comprises INPSNGGT (SEQ ID NO: 1712); the VH CDR3 sequence comprises RRDYRFDMGFDY (SEQ ID NO: 1713); the VL CDR1 sequence comprises KGVSTSGYSY (SEQ ID NO: 1714); the VL CDR2 sequence comprises LAS (SEQ ID NO: 1715); and the VL CDR3 sequence comprises QHSRDLPLT (SEQ ID NO: 1716).
• In some embodiments, at least one arm of the multispecific activatable antibody, e.g., a bispecific activatable antibody, comprises a heavy chain amino acid sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to an amino acid sequence selected from the group consisting of SEQ ID NO: 1, 5, 9, 13, 17, 21, 23, 25, 27, 29, 31, 33, 35, and 37. In some embodiments, at least one arm of the multispecific activatable antibody, e.g., a bispecific activatable antibody, comprises a heavy chain amino acid sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to an amino acid sequence selected from the group consisting of SEQ ID NO: 21, 23, 25, 27, 29, 31, 33, 35, and 37.
• In some embodiments, at least one arm of the multispecific activatable antibody, e.g., a bispecific activatable antibody, comprises a light chain amino acid that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to an amino acid sequence selected from the group consisting of SEQ ID NO: 39, 41, 43, 45, 47, 49, 51, 53, 55, 57, and 59.
• In some embodiments, at least one arm of the multispecific activatable antibody, e.g., a bispecific activatable antibody, comprises a heavy chain amino acid sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to an amino acid sequence selected from the group consisting of SEQ ID NO: 1, 5, 9, 13, 17, 21, 23, 25, 27, 29, 31, 33, 35, and 37, and a light chain amino acid that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to an amino acid sequence selected from the group consisting of SEQ ID NO: 3, 7, 11, 15, 19, 39, 41, 43, 45, 47, 49, 51, 53, 55, 57, and 59. In some embodiments, at least one arm of the multispecific activatable antibody, e.g., a bispecific activatable antibody, comprises a heavy chain amino acid sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to an amino acid sequence selected from the group consisting of SEQ ID NO: 21, 23, 25, 27, 29, 31, 33, 35, and 37, and a light chain amino acid that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to an amino acid sequence selected from the group consisting of SEQ ID NO: 39, 41, 43, 45, 47, 49, 51, 53, 55, 57, and 59.
• In some embodiments, at least one arm of the multispecific activatable antibody, e.g., a bispecific activatable antibody, includes a heavy chain amino acid sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to the amino acid sequence of SEQ ID NO: 1346, and a light chain amino acid that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to the amino acid sequence of SEQ ID NO: 626.
• In some embodiments, at least one arm of the multispecific activatable antibody, e.g., a bispecific activatable antibody, includes a heavy chain amino acid sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to the amino acid sequence of SEQ ID NO: 1514, and a light chain amino acid that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical to the amino acid sequence of SEQ ID NO: 638.
• In some embodiments, at least one arm of the multispecific activatable antibody, e.g., a bispecific activatable antibody, comprises a combination of a variable heavy chain complementarity determining region 1 (VH CDR1, also referred to herein as CDRH1) sequence, a variable heavy chain complementarity determining region 2 (VH CDR2, also referred to herein as CDRH2) sequence, a variable heavy chain complementarity determining region 3 (VH CDR3, also referred to herein as CDRH3) sequence, a variable light chain complementarity determining region 1 (VL CDR1, also referred to herein as CDRL1) sequence, a variable light chain complementarity determining region 2 (VL CDR2, also referred to herein as CDRL2) sequence, and a variable light chain complementarity determining region 3 (VL CDR3, also referred to herein as CDRL3) sequence, wherein at least one CDR sequence is selected from the group consisting of a VH CDR1 sequence shown in Table 8; a VH CDR2 sequence shown in Table 8; a VH CDR3 sequence shown in Table 8; a VL CDR1 sequence shown in Table 8; a VL CDR2 sequence shown in Table 8; and a VL CDR3 sequence shown in Table 8.
• In some embodiments, at least one arm of the multispecific activatable antibody, e.g., a bispecific activatable antibody, comprises a combination of a VH CDR1 sequence, a VH CDR2 sequence, a VH CDR3 sequence, a VL CDR1 sequence, a VL CDR2 sequence, and a VL CDR3 sequence, wherein at least one CDR sequence is selected from the group consisting of a VH CDR1 sequence that includes a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to a VH CDR1 sequence shown in Table 8; a VH CD2 sequence that includes a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to a VH CDR2 sequence shown in Table 8; a VH CDR3 sequence that includes a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to a VH CDR3 sequence shown in Table 8; a VL CDR1 sequence that includes a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to a VL CDR1 sequence shown in Table 8; a VL CDR2 sequence that includes a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to a VL CDR2 sequence shown in Table 8; and a VL CDR3 sequence that includes a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to a VL CDR3 sequence shown in Table 8.
• In some embodiments, at least one arm of the multispecific activatable antibody, e.g., a bispecific activatable antibody, comprises a combination of a VH CDR1 sequence, a VH CDR2 sequence, a VH CDR3 sequence shown in a single row in Table 8, and a VL CDR1 sequence, a VL CDR2 sequence, and a VL CDR3 sequence shown in a single row in Table 8.
• In some embodiments, the antibody comprises a heavy chain that comprises a combination of a VH CDR1 sequence, a VH CDR2 sequence, and a VH CDR3 sequence, wherein the combination is a combination of the three heavy chain CDR sequences (VH CDR1, VH CDR2, VH CDR3) shown in a single row in Table 8.
• In some embodiments, at least one arm of the multispecific activatable antibody, e.g., a bispecific activatable antibody, comprises a combination of a VH CDR1 sequence, a VH CDR2 sequence, a VH CDR3 sequence shown in a single row in Table 8, and a VL CDR1 sequence, a VL CDR2 sequence, and a VL CDR3 sequence shown in a single row in Table 8, wherein each CDR sequence in the combination comprises a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to the corresponding VH CDR sequence shown in a single row in Table 8 and the corresponding VL CDR sequence shown in a single row in Table 8.
• In some embodiments, the antibody comprises a heavy chain that comprises a combination of a VH CDR1 sequence, a VH CDR2 sequence, and a VH CDR3 sequence, wherein each CDR sequence in the combination comprises a sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to the corresponding CDR sequence in a combination of three heavy chain CDR sequences (VH CDR1, VH CDR2, VH CDR3) shown in a single row in Table 8.
• In some embodiments, the anti-PD-1 antibodies and/or activatable anti-PD-1 antibodies described herein are used in conjunction with one or more additional agents or a combination of additional agents. Suitable additional agents include other experimental anti-cancer agents in development for specific applications, current pharmaceutical and/or surgical therapies for an intended application, such as, for example, cancer. For example, the anti-PD-1 antibodies and/or activatable anti-PD-1 antibodies can be used in conjunction with an additional chemotherapeutic or anti-neoplastic agent.
• In some embodiments, the additional agent includes at least one experimental anti-cancer agent in development for specific applications. In some embodiments, the additional agent includes at least one agent that is already approved for one indication but is being tested in another. In some embodiments, the additional agent includes at least one agent that is not currently approved in any indication but is being tested in one or more indications for the purposes of obtaining regulatory approval. In some embodiments, the additional agent includes at least one agent that is a pharmaceutical therapy for an intended application. In some embodiments, the additional agent includes at least one agent that is a surgical therapy for cancer. In some embodiments, the additional agent includes at least one agent that is a pharmaceutical therapy for an intended application. In some embodiments, the additional agent includes at least one agent that is a surgical therapy for cancer. In some embodiments, the additional agent is a chemotherapeutic agent. In some embodiments, the additional agent is an anti-neoplastic agent. In some embodiments, the additional agents are a combination of any two or more of these agents.
• In some embodiments, the additional agent(s) is a chemotherapeutic agent, such as a chemotherapeutic agent selected from the group consisting of docetaxel, paclitaxel, abraxane (i.e., albumin-conjugated paclitaxel), doxorubicin, oxaliplatin, carboplatin, cisplatin, irinotecan, and gemcitabine.
• In some embodiments, the additional agent(s) is a checkpoint inhibitor, a kinase inhibitor, an agent targeting inhibitors in the tumor microenvironment, and/or a T cell or NK agonist. In some embodiments, the additional agent(s) is radiation therapy, alone or in combination with another additional agent(s) such as a chemotherapeutic or anti-neoplastic agent. In some embodiments, the additional agent(s) is a vaccine, an oncovirus, and/or a DC-activating agent such as, by way of non-limiting example, a toll-like receptor (TLR) agonist and/or α-CD40. In some embodiments, the additional agent(s) is a tumor-targeted antibody designed to kill the tumor via ADCC or via direct conjugation to a toxin (e.g., an antibody drug conjugate (ADC).
• In some embodiments, the checkpoint inhibitor is an inhibitor of a target selected from the group consisting of CTLA-4, LAG-3, PD-1, PD-1, TIGIT, TIM-3, B7H4, BTLA, and Vista. In some embodiments, the kinase inhibitor is selected from the group consisting of B-RAFi, MEKi, and Btk inhibitors, such as ibrutinib. In some embodiments, the kinase inhibitor is crizotinib. In some embodiments, the B-RAF inhibitor is vemurafenib. In some embodiments, the tumor microenvironment inhibitor is selected from the group consisting of an IDO inhibitor, an α-CSF1R inhibitor, an α-CCR4 inhibitor, a TGF-beta, a myeloid-derived suppressor cell, or a T-regulatory cell. In some embodiments, the agonist is selected from the group consisting of Ox40, GITR, CD137, ICOS, CD27, and HVEM.
• In some embodiments, the inhibitor is a CTLA-4 inhibitor. In some embodiments, the inhibitor is a LAG-3 inhibitor. In some embodiments, the inhibitor is a PD-1 inhibitor. In some embodiments, the inhibitor is a PD-1 inhibitor. In some embodiments, the inhibitor is a TIGIT inhibitor. In some embodiments, the inhibitor is a TIM-3 inhibitor. In some embodiments, the inhibitor is a B7H4 inhibitor. In some embodiments, the inhibitor is a Vista inhibitor. In some embodiments, the inhibitor is a B-RAFi inhibitor. In some embodiments, the inhibitor is a MEKi inhibitor. In some embodiments, the inhibitor is a Btk inhibitor. In some embodiments, the inhibitor is ibrutinib. In some embodiments, the inhibitor is crizotinib. In some embodiments, the inhibitor is an IDO inhibitor. In some embodiments, the inhibitor is an α-CSF1R inhibitor. In some embodiments, the inhibitor is an α-CCR4 inhibitor. In some embodiments, the inhibitor is a TGF-beta. In some embodiments, the inhibitor is a myeloid-derived suppressor cell. In some embodiments, the inhibitor is a T-regulatory cell.
• In some embodiments, the agonist is O×40. In some embodiments, the agonist is GITR. In some embodiments, the agonist is CD137. In some embodiments, the agonist is ICOS. In some embodiments, the agonist is CD27. In some embodiments, the agonist is HVEM.
• In some embodiments, the anti-PD-1 antibody and/or activatable antibody is administered during and/or after treatment in combination with one or more additional agents such as, for example, a chemotherapeutic agent, an anti-inflammatory agent, and/or an immunosuppressive agent. In some embodiments, the anti-PD-1 antibody and/or activatable anti-PD-1 antibody and the additional agent are formulated into a single therapeutic composition, and the anti-PD-1 antibody and/or activatable anti-PD-1 antibody and additional agent are administered simultaneously. Alternatively, the anti-PD-1 antibody and/or activatable anti-PD-1 antibody and additional agent are separate from each other, e.g., each is formulated into a separate therapeutic composition, and the anti-PD-1 antibody and/or activatable anti-PD-1 antibody and the additional agent are administered simultaneously, or the anti-PD-1 antibody and/or activatable anti-PD-1 antibody and the additional agent are administered at different times during a treatment regimen. For example, the anti-PD-1 antibody and/or activatable anti-PD-1 antibody is administered prior to the administration of the additional agent, the anti-PD-1 antibody and/or activatable anti-PD-1 antibody is administered subsequent to the administration of the additional agent, or the anti-PD-1 antibody and/or activatable anti-PD-1 antibody and the additional agent are administered in an alternating fashion. As described herein, the anti-PD-1 antibody and/or activatable anti-PD-1 antibody and additional agent are administered in single doses or in multiple doses.
• In some embodiments, the anti-PD-1 antibody and/or activatable anti-PD-1 antibody and the additional agent(s) are administered simultaneously. For example, the anti-PD-1 antibody and/or activatable anti-PD-1 antibody and the additional agent(s) can be formulated in a single composition or administered as two or more separate compositions. In some embodiments, the anti-PD-1 antibody and/or activatable anti-PD-1 antibody and the additional agent(s) are administered sequentially, or the anti-PD-1 antibody and/or activatable anti-PD-1 antibody and the additional agent are administered at different times during a treatment regimen.
• In some embodiments, the anti-PD-1 antibody and/or activatable anti-PD-1 antibody is administered during and/or after treatment in combination with one or more additional agents such as, by way of non-limiting example, a chemotherapeutic agent, an anti-inflammatory agent, and/or an immunosuppressive agent, such as an alkylating agent, an anti-metabolite, an anti-microtubule agent, a topoisomerase inhibitor, a cytotoxic antibiotic, and/or any other nucleic acid damaging agent. In some embodiments, the additional agent is a taxane, such as paclitaxel (e.g., Abraxane®). In some embodiments, the additional agent is an anti-metabolite, such as gemcitabine. In some embodiments, the additional agent is an alkylating agent, such as platinum-based chemotherapy, such as carboplatin or cisplatin. In some embodiments, the additional agent is a targeted agent, such as a kinase inhibitor, e.g., sorafenib or erlotinib. In some embodiments, the additional agent is a targeted agent, such as another antibody, e.g., a monoclonal antibody (e.g., bevacizumab), a bispecific antibody, or a multispecific antibody. In some embodiments, the additional agent is a proteosome inhibitor, such as bortezomib or carfilzomib. In some embodiments, the additional agent is an immune modulating agent, such as lenolidominde or IL-2. In some embodiments, the additional agent is radiation. In some embodiments, the additional agent is an agent considered standard of care by those skilled in the art. In some embodiments, the additional agent is a chemotherapeutic agent well known to those skilled in the art.
• In some embodiments, the additional agent is another antibody or antigen-binding fragment thereof and/or another activatable antibody or antigen-binding fragment thereof. In some embodiments the additional agent is another antibody or antigen-binding fragment thereof and/or another activatable antibody or antigen-binding fragment thereof against the same target as the first antibody or antigen-binding fragment thereof and/or an activatable antibody or antigen-binding fragment thereof, e.g., against PD-1. In some embodiments the additional agent is another antibody or antigen-binding fragment thereof and/or another activatable antibody or antigen-binding fragment thereof against a target different than the target of the first antibody or antigen-binding fragment thereof, the first conjugated antibody or antigen-binding fragment thereof and/or activatable antibody or antigen-binding fragment thereof.
• As a non-limiting example, the antibody or antigen-binding fragment and/or the AB of an activatable antibody is a binding partner for any target listed in Table 1.

• TABLE 1
  Exemplary Targets

  1-92-LFA-3	CD52	DL44	HVEM	LIF-R	STEAP1
  Alpha-4	CD56	DLK1	Hyaluronidase	Lewis X	STEAP2
  integrin
  Alpha-V	CD64	DLL4	ICOS	LIGHT	TAG-72
  integrin
  alpha4beta1	CD70	DPP-4	IFNalpha	LRP4	TAPA1
  integrin
  alpha4beta7	CD71	DSG1	IFNbeta	LRRC26	TGFbeta
  integrin
  AGR2	CD74	EGFR	IFNgamma	MCSP	TIGIT
  Anti-Lewis-Y		EGFRviii	IgE	Mesothelin	TIM-3
  Apelin J	CD80	Endothelin B	IgE Receptor	MRP4	TLR2
  receptor		receptor	(FceRI)
  		(ETBR)
  APRIL	CD81	ENPP3	IGF	MUC1	TLR4
  B7-H4	CD86	EpCAM	IGF1R	Mucin-16	TLR6
  				(MUC16,
  				CA-125)
  BAFF	CD95	EPHA2	IL1B	Na/K ATPase	TLR7
  BTLA	CD117	EPHB2	IL1R	Neutrophil	TLR8
  				elastase
  C5	CD125	ERBB3	IL2	NGF	TLR9
  complement
  C-242	CD132	F protein of	IL11	Nicastrin	TMEM31
  	(IL-2RG)	RSV
  CA9	CD133	FAP	IL12	Notch	TNFalpha
  				Receptors
  CA19-9	CD137	FGF-2	IL12p40	Notch 1	TNFR
  (Lewis a)
  Carbonic	CD138	FGF8	IL-12R,	Notch 2	TNFRS12
  anhydrase 9			IL-12Rbeta1		A
  CD2	CD166	FGFR1	IL13	Notch 3	TRAIL-R1
  CD3	CD172A	FGFR2	IL13R	Notch 4	TRAIL-R2
  CD6	CD248	FGFR3	IL15	NOV	Transferrin
  CD9	CDH6	FGFR4	IL17	OSM-R	Transferrin
  					receptor
  CD11a	CEACAM5	Folate	IL18	OX-40	TRK-A
  	(CEA)	receptor
  CD19	CEACAM6	GAL3ST1	IL21	PAR2	TRK-B
  	(NCA-90)
  CD20	CLAUDIN-3	G-CSF	IL23	PDGF-AA	uPAR
  CD22	CLAUDIN-4	G-CSFR	IL23R	PDGF-BB	VAP1
  CD24	cMet	GD2	IL27/IL27R	PDGFRalpha	VCAM-1
  			(wsx1)
  CD25	Collagen	GITR	IL29	PDGFRbeta	VEGF
  CD27	Cripto	GLUT1	IL-31R	PD-1	VEGF-A
  CD28	CSFR	GLUT4	IL31/IL31R	PD-L1	VEGF-B
  CD30	CSFR-1	GM-CSF	IL2R	PD-L2	VEGF-C
  CD33	CTLA-4	GM-CSFR	IL4	Phosphatidyl-	VEGF-D
  				serine
  CD38	CTGF	GP IIb/IIIa	IL4R	P1GF	VEGFR1
  		receptors
  CD40	CXCL10	Gp130	IL6, IL6R	PSCA	VEGFR2
  CD40L	CXCL13	GPIIB/IIIA	Insulin	PSMA	VEGFR3
  			Receptor
  CD41	CXCR1	GPNMB	Jagged	RAAG12	VISTA
  			Ligands
  CD44	CXCR2	GRP78	Jagged 1	RAGE	WISP-1
  CD44v6		HER2/neu	Jagged 2	SLC44A4	WISP-2
  CD47	CXCR4	HGF	LAG-3	Sphingosine 1	WISP-3
  				Phosphate
  CD51	CYR61	hGH

• As a non-limiting example, the antibody or antigen-binding fragment and/or the AB of an activatable antibody is or is derived from an antibody listed in Table 2.

• TABLE 2
  Exemplary sources for Abs

  Antibody Trade Name (antibody name)	Target
  Avastin ™ (bevacizumab)	VEGF
  Lucentis ™ (ranibizumab)	VEGF
  Erbitux ™ (cetuximab)	EGFR
  Vectibix ™ (panitumumab)	EGFR
  Remicade ™ (infliximab)	TNFα
  Humira ™ (adalimumab)	TNFα
  Tysabri ™ (natalizumab)	Integrinα4
  Simulect ™ (basiliximab)	IL2R
  Soliris ™ (eculizumab)	Complement C5
  Raptiva ™ (efalizumab)	CD11a
  Bexxar ™ (tositumomab)	CD20
  Zevalin ™ (ibritumomab tiuxetan)	CD20
  Rituxan ™ (rituximab)	CD20
  Ocrelizumab	CD20
  Arzerra ™ (ofatumumab)	CD20
  Gazyva ™ (Obinutuzumab)	CD20
  Zenapax ™ (daclizumab)	CD25
  Adcetris ™ (brentuximab vedotin)	CD30
  Myelotarg ™ (gemtuzumab)	CD33
  Mylotarg ™ (gemtuzumab ozogamicin)	CD33
  Campath ™ (alemtuzumab)	CD52
  ReoPro ™ (abiciximab)	Glycoprotein receptor IIb/IIIa
  Xolair ™ (omalizumab)	IgE
  Herceptin ™ (trastuzumab)	Her2
  Kadcyla ™ (trastuzumab emtansine)	Her2
  Synagis ™ (palivizumab)	F protein of RSV
  (ipilimumab)	CTLA-4
  (tremelimumab)	CTLA-4
  Hu5c8	CD40L
  (pertuzumab)	Her2-neu
  (ertumaxomab)	CD3/Her2-neu
  Orencia ™ (abatacept)	CTLA-4
  (tanezumab)	NGF
  (bavituximab)	Phosphatidylserine
  (zalutumumab)	EGFR
  (mapatumumab)	EGFR
  (matuzumab)	EGFR
  (nimotuzumab)	EGFR
  ICR62	EGFR
  mAb 528	EGFR
  CH806	EGFR
  MDX-447	EGFR/CD64
  (edrecolomab)	EpCAM
  RAV12	RAAG12
  huJ591	PSMA
  Enbrel ™ (etanercept)	TNF-R
  Amevive ™ (alefacept)	1-92-LFA-3
  Antril ™, Kineret ™ (ankinra)	IL-1Ra
  GC1008	TGFbeta
  	Notch, e.g., Notch 1
  	Jagged 1 or Jagged 2
  (adecatumumab)	EpCAM
  (figitumumab)	IGF1R
  (tocilizumab)	IL-6 receptor
  Stelara ™ (ustekinumab)	IL-12/IL-23
  Prolia ™ (denosumab)	RANKL

• In some embodiments, the additional antibody or antigen binding fragment thereof and/or activatable antibody or antigen binding fragment thereof is a monoclonal antibody, domain antibody, single chain, Fab fragment, a F(ab′)₂ fragment, a scFv, a scAb, a dAb, a single domain heavy chain antibody, or a single domain light chain antibody. In some embodiments, the additional antibody or antigen binding fragment thereof and/or activatable antibody or antigen binding fragment thereof is a mouse, other rodent, chimeric, humanized or fully human monoclonal antibody.
• The disclosure also provides methods of producing an anti-PD-1 antibody and/or activatable anti-PD-1 antibody polypeptide by culturing a cell under conditions that lead to expression of the polypeptide, wherein the cell comprises an isolated nucleic acid molecule encoding an antibody and/or an activatable antibody described herein, and/or vectors that include these isolated nucleic acid sequences. The disclosure provides methods of producing an antibody and/or activatable antibody by culturing a cell under conditions that lead to expression of the antibody and/or activatable antibody, wherein the cell comprises an isolated nucleic acid molecule encoding an antibody and/or an activatable antibody described herein, and/or vectors that include these isolated nucleic acid sequences.
• The invention also provides a method of manufacturing activatable antibodies that in an activated state binds PD-1 by (a) culturing a cell comprising a nucleic acid construct that encodes the activatable antibody under conditions that lead to expression of the activatable antibody, wherein the activatable antibody comprises a masking moiety (MM), a cleavable moiety (CM), and an antibody or an antigen binding fragment thereof (AB) that specifically binds PD-1, (i) wherein the CM is a polypeptide that functions as a substrate for a protease; and (ii) wherein the CM is positioned in the activatable antibody such that, when the activatable antibody is in an uncleaved state, the MM interferes with specific binding of the AB to PD-1 and in a cleaved state the MM does not interfere or compete with specific binding of the AB to PD-1; and (b) recovering the activatable antibody. Suitable AB, MM, and/or CM include any of the AB, MM, and/or CM disclosed herein.
• In some embodiments, the activatable antibody in the uncleaved state has the structural arrangement from N-terminus to C-terminus as follows: MM-CM-AB or AB-CM-MM. In some embodiments, the activatable antibody comprises a linking peptide between the MM and the CM. In some embodiments, the activatable antibody comprises a linking peptide between the CM and the AB. In some embodiments, the activatable antibody comprises a first linking peptide (LP1) and a second linking peptide (LP2), and wherein the activatable antibody in the uncleaved state has the structural arrangement from N-terminus to C-terminus as follows: MM-LP1-CM-LP2-AB or AB-LP2-CM-LP1-MM. In some embodiments, the activatable antibody in the uncleaved state has the structural arrangement from N-terminus to C-terminus as follows: spacer-MM-LP1-CM-LP2-AB or AB-LP2-CM-LP1-MM-spacer.
• In some embodiments, the two linking peptides need not be identical to each other.
• In some embodiments, at least one of LP1 or LP2 comprises an amino acid sequence selected from the group consisting of (GS)_n, (GGS)_n, (GSGGS)_n (SEQ ID NO: 363) and (GGGS)_n (SEQ ID NO: 364), where n is an integer of at least one.
• In some embodiments, at least one of LP1 or LP2 comprises an amino acid sequence selected from the group consisting of GGSG (SEQ ID NO: 365), GGSGG (SEQ ID NO: 366), GSGSG (SEQ ID NO: 367), GSGGG (SEQ ID NO: 368), GGGSG (SEQ ID NO: 369), and GSSSG (SEQ ID NO: 370).
• In some embodiments, LP1 comprises the amino acid sequence GSSGGSGGSGGSG (SEQ ID NO: 371), GSSGGSGGSGG (SEQ ID NO: 372), GSSGGSGGSGGS (SEQ ID NO: 373), GSSGGSGGSGGSGGGS (SEQ ID NO: 374), GSSGGSGGSG (SEQ ID NO: 375), GSSGGSGGSGS (SEQ ID NO: 376), GGGSSGGS (SEQ ID NO: 65), or GGGSSGG (SEQ ID NO: 1040).
• In some embodiments, LP2 comprises the amino acid sequence GSS, GGS, GGGS (SEQ ID NO: 377), GSSGT (SEQ ID NO: 378) or GSSG (SEQ ID NO: 379).
• The invention provides methods of preventing, delaying the progression of, treating, alleviating a symptom of, or otherwise ameliorating a disorder or disease in a subject by administering to a subject in need thereof a therapeutically effective amount of an anti-PD-1 antibody, conjugated anti-PD-1 antibody, activatable anti-PD-1 antibody and/or conjugated activatable anti-PD-1 antibody described herein.
• The invention also provides a method of reducing immune suppression comprising administering to a subject in need thereof a therapeutically effective amount of an anti-PD-1 antibody and/or activatable anti-PD-1 antibody described herein. In some embodiments, the immune suppression is suppression of T cell activity. In some embodiments, the immune suppression is mediated by engagement of PD-1 on T cells to PD-L1 or PD-L2 on tumor cells or other immune cells. In some embodiments, the invention provides a method to reduce or inhibit binding of PD-L1 (also referred to herein as PDL1) and/or PD-L2 (also referred to herein as PDL2), to PD-1 on T cells. The ligands PD-L1 and/or PD-L2 are often found on tumor cells or other immune cells.
• The invention also provides methods of preventing, delaying the progression of, treating, alleviating a symptom of, or otherwise ameliorating cancer in a subject by administering a therapeutically effective amount of an anti-PD-1 antibody and/or activatable anti-PD-1 antibody described herein to a subject in need thereof. PD-1 is known to be expressed on immune cells, such as T cells, in a variety of cancers, such as, by way of non-limiting example, melanoma, non-small cell lung cancer, nasopharyngeal cancer, glioblastoma/mixed glioma, colon adenocarcinoma, hepatocellular carcinoma, urothelial cancer, multiple myeloma, ovarian cancer, gastric carcinoma, esophageal cancer, pancreatic cancer, renal cell carcinoma (RCC), breast cancer, lymphomas, such as Hodgkin's lymphoma, and leukemias. (See e.g., Chen et al., “Molecular Pathways: Next-Generation Immunotherapy—Inhibiting Programmed Death-Ligand 1 and Programmed Death-1,” Clin. Can. Res., vol. 18: 6580-6587 (2012), the contents of which are hereby incorporated by reference in their entirety).
• In some embodiments, the cancer is a bladder cancer, a bone cancer, a breast cancer, a carcinoid, a cervical cancer, a cholangiocarcinoma, a colon cancer, an endometrial cancer, a glioma, a head and neck cancer, a liver cancer, a lung cancer, a lymphoma, such as Hodgkin's lymphoma, a melanoma, an ovarian cancer, a pancreatic cancer, a prostate cancer, a renal cancer, a sarcoma, a skin cancer, a stomach cancer, a testis cancer, a thymus cancer, a thyroid cancer, a urogenital cancer, and/or a urothelial cancer.
• In some embodiments, the cancer is selected from the group consisting of melanoma (MEL), renal cell carcinoma (RCC), squamous non-small cell lung cancer (NSCLC), non-squamous NSCLC, colorectal cancer (CRC), castration-resistant prostate cancer (CRPC), hepatocellular carcinoma (HCC), squamous cell carcinoma of the head and neck, thymoma, carcinomas of the esophagus, ovary, gastrointestinal tract and breast, or a hematologic malignancy such as multiple myeloma, B-cell lymphoma, T-cell lymphoma, Hodgkin's lymphoma, primary mediastinal B-cell lymphoma, and chronic myelogenous leukemia.
• The invention also provides methods of treating cancer patients with an autoimmune or inflammatory disease by administering a therapeutically effective amount of an anti-PD-1 antibody and/or activatable anti-PD-1 antibody described herein to a subject in need thereof. In some embodiments, the autoimmune disease is colitis, RA, pancreatitis, diabetes, or pneumonitis.
• An anti-PD-1 antibody and/or an activatable anti-PD-1 antibody used in any of the embodiments of these methods and uses can be administered at any stage of the disease. For example, such an anti-PD-1 antibody and/or activatable anti-PD-1 antibody can be administered to a patient suffering cancer of any stage, from early to metastatic. The terms subject and patient are used interchangeably herein.
• In some embodiments, the subject is a mammal, such as a human, non-human primate, companion animal (e.g., cat, dog, horse), farm animal, work animal, or zoo animal. In some embodiments, the subject is a human. In some embodiments, the subject is a companion animal. In some embodiments, the subject is an animal in the care of a veterinarian.
• The anti-PD-1 antibody and/or activatable anti-PD-1 antibody and therapeutic formulations thereof are administered to a subject suffering from or susceptible to a disease or disorder associated with immune suppression, such as immune suppression mediated by engagement of PD-1 on T cells by PD-L1 or PD-L2 on tumor cells or other immune cells. In some embodiments, the immune suppression is suppression of T cell activity. A subject suffering from or susceptible to a disease or disorder associated with such immune suppression is identified using any of a variety of methods known in the art. For example, subjects suffering from cancer or other neoplastic condition are identified using any of a variety of clinical and/or laboratory tests such as, physical examination and blood, urine and/or stool analysis to evaluate health status. For example, subjects suffering from inflammation and/or an inflammatory disorder are identified using any of a variety of clinical and/or laboratory tests such as physical examination and/or bodily fluid analysis, e.g., blood, urine and/or stool analysis, to evaluate health status.
• Administration of an anti-PD-1 antibody and/or activatable anti-PD-1 antibody to a patient suffering from a disease or disorder associated with immune suppression, such as immune suppression mediated by engagement of PD-1 on T cells by PD-L1 or PD-L2 on tumor cells or other immune cells, is considered successful if any of a variety of laboratory or clinical objectives is achieved. For example, administration of an anti-PD-1 antibody, and/or activatable anti-PD-1 antibody to a patient suffering from a disease or disorder associated with such immune suppression is considered successful if one or more of the symptoms associated with the disease or disorder is alleviated, reduced, inhibited or does not progress to a further, i.e., worse, state. Administration of an anti-PD-1 antibody and/or conjugated activatable anti-PD-1 antibody to a patient suffering from a disease or disorder associated with immune suppression, such as immune suppression mediated by engagement of PD-1 on T cells to PD-L1 or PD-L2 on tumor cells or other immune cells, is considered successful if the disease or disorder enters remission or does not progress to a further, i.e., worse, state.
• In some embodiments, the anti-PD-1 antibody and/or conjugated activatable anti-PD-1 antibody is administered during and/or after treatment in combination with one or more additional agents such as, for example, a chemotherapeutic agent, an anti-inflammatory agent, and/or an immunosuppressive agent. In some embodiments, the anti-PD-1 antibody and/or activatable anti-PD-1 antibody and the additional agent(s) are administered simultaneously. For example, the anti-PD-1 antibody and/or activatable anti-PD-1 antibody and the additional agent(s) can be formulated in a single composition or administered as two or more separate compositions. In some embodiments, the anti-PD-1 antibody and/or activatable anti-PD-1 antibody and the additional agent(s) are administered sequentially.
• The invention also provides methods and kits for using the activatable anti-PD-1 antibodies in a variety of diagnostic and/or prophylactic indications. For example, the invention provides methods and kits for detecting the presence or absence of a cleaving agent and a target of interest in a subject or a sample by (i) contacting a subject or sample with an anti-PD-1 activatable antibody, wherein the anti-PD-1 activatable antibody comprises a masking moiety (MM), a cleavable moiety (CM) that is cleaved by the cleaving agent, and an antigen binding domain or fragment thereof (AB) that specifically binds the target of interest, wherein the anti-PD-1 activatable antibody in an uncleaved, non-activated state comprises a structural arrangement from N-terminus to C-terminus as follows: MM-CM-AB or AB-CM-MM; (a) wherein the MM is a peptide that inhibits binding of the AB to PD-1, and wherein the MM does not have an amino acid sequence of a naturally occurring binding partner of the AB and is not a modified form of a natural binding partner of the AB; and (b) wherein, when the AB is in an uncleaved, non-activated state, the MM interferes with specific binding of the AB to PD-1, and when the AB is in a cleaved, activated state the MM does not interfere or compete with specific binding of the AB to PD-1; and (ii) measuring a level of activated anti-PD-1 activatable antibody in the subject or sample, wherein a detectable level of activated anti-PD-1 activatable antibody in the subject or sample indicates that the cleaving agent and PD-1 are present in the subject or sample and wherein no detectable level of activated anti-PD-1 activatable antibody in the subject or sample indicates that the cleaving agent, PD-1 or both the cleaving agent and PD-1 are absent in the subject or sample.
• In some embodiments, the activatable anti-PD-1 antibody is an activatable anti-PD-1 antibody to which a therapeutic agent is conjugated. In some embodiments, the activatable anti-PD-1 antibody is not conjugated to an agent. In some embodiments, the activatable anti-PD-1 antibody comprises a detectable label. In some embodiments, the detectable label is positioned on the AB. In some embodiments, measuring the level of activatable anti-PD-1 antibody in the subject or sample is accomplished using a secondary reagent that specifically binds to the activated antibody, wherein the reagent comprises a detectable label. In some embodiments, the secondary reagent is an antibody comprising a detectable label.
• In some embodiments of these methods and kits, the activatable anti-PD-1 antibody includes a detectable label. In some embodiments of these methods and kits, the detectable label includes an imaging agent, a contrasting agent, an enzyme, a fluorescent label, a chromophore, a dye, one or more metal ions, or a ligand-based label. In some embodiments of these methods and kits, the imaging agent comprises a radioisotope. In some embodiments of these methods and kits, the radioisotope is indium or technetium. In some embodiments of these methods and kits, the contrasting agent comprises iodine, gadolinium or iron oxide. In some embodiments of these methods and kits, the enzyme comprises horseradish peroxidase, alkaline phosphatase, or β-galactosidase. In some embodiments of these methods and kits, the fluorescent label comprises yellow fluorescent protein (YFP), cyan fluorescent protein (CFP), green fluorescent protein (GFP), modified red fluorescent protein (mRFP), red fluorescent protein tdimer2 (RFP tdimer2), HCRED, or a europium derivative. In some embodiments of these methods and kits, the luminescent label comprises an N-methylacrydium derivative. In some embodiments of these methods, the label comprises an Alexa Fluor® label, such as Alex Fluor® 680 or Alexa Fluor® 750. In some embodiments of these methods and kits, the ligand-based label comprises biotin, avidin, streptavidin or one or more haptens.
• In some embodiments of these methods and kits, the subject is a mammal. In some embodiments of these methods, the subject is a human. In some embodiments, the subject is a non-human mammal, such as a non-human primate, companion animal (e.g., cat, dog, horse), farm animal, work animal, or zoo animal. In some embodiments, the subject is a rodent.
• In some embodiments of these methods and kits, the method is an in vivo method. In some embodiments of these methods, the method is an in situ method. In some embodiments of these methods, the method is an ex vivo method. In some embodiments of these methods, the method is an in vitro method.
• In some embodiments of the methods and kits, the method is used to identify or otherwise refine a patient population suitable for treatment with an anti-PD-1 activatable antibody of the disclosure, followed by treatment by administering that activatable anti-PD-1 antibody to a subject in need thereof. For example, patients that test positive for both the target (e.g., PD-1) and a protease that cleaves the substrate in the cleavable moiety (CM) of the anti-PD-1 activatable antibody being tested in these methods are identified as suitable candidates for treatment with such an anti-PD-1 activatable antibody comprising such a CM, and the patient is then administered a therapeutically effective amount of the activatable anti-PD-1 antibody that was tested. Likewise, patients that test negative for either or both of the target (e.g., PD-1) and the protease that cleaves the substrate in the CM in the activatable antibody being tested using these methods might be identified as suitable candidates for another form of therapy. In some embodiments, such patients can be tested with other anti-PD-1 activatable antibodies until a suitable anti-PD-1 activatable antibody for treatment is identified (e.g., an anti-PD-1 activatable antibody comprising a CM that is cleaved by the patient at the site of disease). In some embodiments, the patient is then administered a therapeutically effective amount of the activatable anti-PD-1 antibody for which the patient tested positive. Suitable AB, MM, and/or CM include any of the AB, MM, and/or CM disclosed herein.
• Pharmaceutical compositions according to the invention can include an antibody of the invention and a carrier. These pharmaceutical compositions can be included in kits, such as, for example, diagnostic kits.
BRIEF DESCRIPTION OF THE DRAWINGS
• FIG. 1 is graph depicting the results of an ELISA binding assay using various murine antibodies that bind human PD-1 (i.e., anti-hPD-1 antibodies) referred to herein as 245-M3, also referred to herein as M3 (VH: SEQ ID NO: 9; VL: SEQ ID NO: 11), 245-M5, also referred to herein as M5 (VH: SEQ ID NO: 13; VL: SEQ ID NO: 15), 136-M13, also referred to herein as M13 (VH: SEQ ID NO: 1; VL: SEQ ID NO: 3), 136-M19, also referred to herein as M19 (VH: SEQ ID NO: 5; VL: SEQ ID NO: 7), and 136-M14, also referred to herein as M14 (VH: SEQ ID NO: 17; VL: SEQ ID NO: 19). The anti-PD-1 antibodies nivolumab (also referred to herein as “nivo” or “NV1”) and pembrolizumab (also referred to herein as “pembro” or “PM1” or “PM1 AB”) were used as positive controls.
• FIG. 2 is a series of graphs demonstrating that various murine anti-hPD-1 antibodies block binding of the ligands human PD-L1 (hPD-L1) and human PD-L2 (hPD-L2) to human PD-1.
• FIG. 3 is a series of graphs demonstrating that various murine anti-hPD-1 antibodies block binding of the ligands human PD-L1 (hPD-L1) and human PD-L2 (hPD-L2) to human PD-1.
• FIG. 4 is a graph depicting binding to human PD-1 of various anti-hPD-1 antibodies of the disclosure referred to herein as A1.0 (VH: SEQ ID NO: 21; VL: SEQ ID NO: 39), A1.2 (VH: SEQ ID NO: 21; VL: SEQ ID NO: 43), and A1.4 (VH: SEQ ID NO: 21; VL: SEQ ID NO: 45) as determined by ELISA. The anti-PD-1 antibody pembrolizumab (“PM1”) was used as positive control.
• FIG. 5 is a graph depicting binding to human PD-1 of various anti-hPD-1 antibodies of the disclosure referred to herein as A1.5 (VH: SEQ ID NO: 21; VL: SEQ ID NO: 47), A1.6 (VH: SEQ ID NO: 21; VL: SEQ ID NO: 49), Ba2 (VH: SEQ ID NO: 29; VL: SEQ ID NO: 57), Bb2 (VH: SEQ ID NO: 31; VL: SEQ ID NO: 57), C1.1 (VH: SEQ ID NO: 33; VL: SEQ ID NO: 41), and D4 (VH: SEQ ID NO: 37; VL: SEQ ID NO: 59) as determined by ELISA. The anti-PD-1 antibodies nivolumab (“NV1”) and pembrolizumab (“PM1”) were used as positive controls.
• FIG. 6 is a series of graphs depicting the ability of various anti-hPD-1 antibodies of the disclosure referred to herein as A1.0, A1.2, and A1.4 to inhibit binding between human PD-1 (hPD-1) and both human PDL-1 (hPDL-1) and human PDL-2 (hPDL-2) as determined by ELISA. The anti-PD-1 antibody pembrolizumab (“PM1”) was used as positive control.
• FIG. 7 is a series of graphs depicting the ability of various anti-hPD-1 antibodies of the disclosure referred to herein as A1.5 and C1.1 to inhibit binding between hPD-1 and both hPDL-1 and hPDL-2 as determined by ELISA. The anti-PD-1 antibodies nivolumab (“NV1”) and pembrolizumab (“PM1”) were used as positive controls.
• FIG. 8 is a graph depicting the ability of various anti-hPD-1 antibodies of the disclosure referred to herein as A1.5, Ba2, Bb2, C1.1, and D4 to inhibit binding between hPD-1 and hPDL-1 as determined by ELISA. The anti-PD-1 antibodies nivolumab (“NV1”) and pembrolizumab (“PM1”) were used as positive controls.
• FIG. 9 is a graph depicting the ability of various anti-hPD-1 antibodies of the disclosure referred to herein as A1.5, Ba2, Bb2, C1.1, and D4 to inhibit binding between hPD-1 and hPDL-2 as determined by ELISA. The anti-PD-1 antibodies nivolumab (“NV1”) and pembrolizumab (“PM1”) were used as positive controls.
• FIG. 10 is a graph depicting that the anti-PD-1 antibody referred to herein as A1.5 specifically binds hPD-1 as determined by ELISA. The A1.5 anti-PD-1 antibody was tested against a panel of human and mouse proteins.
• FIGS. 11A and 11B are a series of graphs depicting the ability of the anti-PD-1 antibody A1.5 to block Fab fragments of the anti-PD-1 antibodies nivolumab (“NV1”) and pembrolizumab (“PM1”) from binding to PD-1. These graphs also demonstrate that the anti-PD-1 antibody A1.5 binds a distinct epitope from either NV1 and/or PM1.
• FIG. 12 is a graph demonstrating that the anti-PD-1 antibody A1.5 has a potency similar to that of nivolumab (“NV1”) and pembrolizumab (“PM1”) measured in a T-cell restimulation assay. In FIG. 12, PMBCs were treated as follows: PBMCs: CMV+HemaCare Donor C were plated at 2×10⁵ cells/well; stimulated with 5 μg/mL CMV lysate+/−anti-PD-1 or isotype control; IFN-γ ELISA assay performed on day 4 supernatant.
• FIG. 13 is a series of graphs demonstrating that the anti-PD-1 antibodies A1.5 and Ba2 bind monomeric human PD-1 (hPD1) with similar or higher affinity than the anti-PD-1 antibodies nivolumab (“Nivo”) and pembrolizumab (“Pembro”).
• FIG. 14 is a series of graphs depicting the binding to human PD-1 by anti-PD-1 antibody A1.4 and by various activatable anti-PD-1 antibodies that include the various masking moieties referred to herein as PD01 (SEQ ID NO: 66), PD02 (SEQ ID NO: 67), PD03 (SEQ ID NO: 68), PD08 (SEQ ID NO: 73), PD09 (SEQ ID NO: 74), and PD10 (SEQ ID NO: 75) as determined by ELISA.
• FIG. 15 is a series of graphs depicting the binding to hPD-1 by anti-PD-1 antibody A1.5 and by various activatable anti-PD-1 antibodies that include the anti-PD-1 antibody A1.5 and the masking moieties referred to herein as PD01 (SEQ ID NO: 66), PD02 (SEQ ID NO: 67), PD03 (SEQ ID NO: 68), PD05 (SEQ ID NO: 70), PD06 (SEQ ID NO: 71) (Plate 1); PD08 (SEQ ID NO: 73), PD09 (SEQ ID NO: 74), PD10 (SEQ ID NO: 75), PD11 (SEQ ID NO: 76), PD12 (SEQ ID NO: 77) (Plate 2); PD13 (SEQ ID NO: 78), PD14 (SEQ ID NO: 79), PD15 (SEQ ID NO: 80), PD16 (SEQ ID NO: 81), PD17 (SEQ ID NO: 82) (Plate 3); PD18 (SEQ ID NO: 83), PD19 (SEQ ID NO: 84), PD20 (SEQ ID NO: 85), PD21 (SEQ ID NO: 86), PD22 (SEQ ID NO: 87) (Plate 4); and PD23 (SEQ ID NO: 88), PD24 (SEQ ID NO: 89) (Plate 5).
• FIG. 16 is a graph depicting the binding to hPD-1 by anti-PD-1 antibody A1.5 and various activatable anti-PD-1 antibodies that include the anti-PD-1 antibody A1.5, the cleavable moiety referred to herein as 3001, which includes the sequence AVGLLAPPGGLSGRSDNH (SEQ ID NO: 318), and the masking moieties referred to herein as PD02, PD12, and PD16.
• FIG. 17 is a series of graphs depicting the binding to hPD-1 by the anti-PD-1 antibody A1.5 and by various activatable anti-PD-1 antibodies that include the anti-PD-1 antibody A1.5, the cleavable moiety referred to herein as 2001, which includes the sequence ISSGLLSGRSDNH (SEQ ID NO: 214), and the masking moieties referred to herein as PD05 (SEQ ID NO: 70), PD06 (SEQ ID NO: 71), PD09 (SEQ ID NO: 74) (upper left panel); PD12 (SEQ ID NO: 77), PD23 (SEQ ID NO: 88), PD25 (SEQ ID NO: 90) (upper right panel); PD26 (SEQ ID NO: 91), PD27 (SEQ ID NO: 92), PD28 (SEQ ID NO: 93) (lower left panel); and PD30 (SEQ ID NO: 95), PD33 (SEQ ID NO: 98), PD35 (SEQ ID NO: 100) (lower right panel).
• FIG. 18 is a series of graphs depicting the binding to hPD-1 by the anti-PD-1 antibody A1.5 and by various activatable anti-PD-1 antibodies that include the anti-PD-1 antibody A1.5 and the masking moieties referred to herein as PD34 (SEQ ID NO: 99), PD06 (SEQ ID NO: 71), PD09 (SEQ ID NO: 74) (upper left panel); PD34 (SEQ ID NO: 99), PD12 (SEQ ID NO: 77), PD17 (SEQ ID NO: 82) (upper right panel); PD34 (SEQ ID NO: 99), PD19 (SEQ ID NO: 84), PD25 (SEQ ID NO: 90) (lower left panel); and PD34 (SEQ ID NO: 99), PD26 (SEQ ID NO: 91), PD28 (SEQ ID NO: 93) (lower right panel).
• FIG. 19 is a graph depicting the ability of anti-PD1 A1.5 activatable antibodies of the disclosure to increase CMV-stimulated IFN-gamma secretion as compared to control hIgG4, but with decreased potency relative to anti-PD1 A1.5 parental antibody. The tested activatable antibodies include the anti-PD-1 antibody A1.5, the cleavable moiety referred to herein as 2001, and the masking moieties referred to herein as PD06, PD05, PD11, PD12, PD14, and PD19. In FIG. 19, PMBCs were treated as follows: PBMCs: CMV+ HemaCare Donor C were plated at 2×10⁵ cells/well; stimulated with 5 μg/mL CMV lysate+/−anti-PD-1 or isotype control; IFN-γ ELISA assay performed on day 4 supernatant.
• FIGS. 20A and 20B are a series of graphs depicting the ability of the anti-PD-1 antibody referred to herein as J43v2 (Heavy Chain (HC): SEQ ID NO: 546; Light Chain (LC): SEQ ID NO: 543) to block murine PD-L1 (mPD-L1) and murine PD-L2 (mPD-L2) from binding to cells expressing murine PD-1 (mPD-1) with single digit nM EC₅₀ values.
• FIG. 21 is a graph depicting the dose-dependent induction of diabetes in NOD mice by the antibody referred to herein as J43v2 m2a (HC: SEQ ID NO: 546; LC: SEQ ID NO: 543).
• FIG. 22 is a series of graphs depicting the binding to hPD-1 by anti-PD-1 antibody J43v2 m2a and by various activatable anti-PD-1 antibodies that include the anti-PD-1 antibody J43v2 m2a and the masking moieties referred to herein as MP01 (SEQ ID NO: 384), MP02 (SEQ ID NO: 385), MP03 (SEQ ID NO: 386), MP04 (SEQ ID NO: 387), MP05 (SEQ ID NO: 388) (upper left panel); MP06 (SEQ ID NO: 389), MP07 (SEQ ID NO: 390), MP08 (SEQ ID NO: 391), MP09 (SEQ ID NO: 392), MP10, also referred to herein as MP010 (SEQ ID NO: 393) (upper right panel); MP11, also referred to herein as MP011 (SEQ ID NO: 394), MP12, also referred to herein as MP012 (SEQ ID NO: 395), MP13, also referred to herein as MP013 (SEQ ID NO: 396), MP14, also referred to herein as MP014 (SEQ ID NO: 397) (bottom panel).
• FIG. 23 is a graph depicting the binding to hPD-1 by the anti-PD-1 antibody J43v2 m2a and by various activatable anti-PD-1 antibodies that include the anti-PD-1 antibody J43v2 m2a, the cleavable moiety referred to herein as 2001, and the masking moieties referred to herein as MP5-2 (SEQ ID NO: 565), MP7-1 (SEQ ID NO: 558), MP7-5 (SEQ ID NO: 562), MP8-2 (SEQ ID NO: 549) (upper panel); and MP7-1 (SEQ ID NO: 558), MP8-9 (SEQ ID NO: 556), MP8-8 (SEQ ID NO: 555) (lower panel).
• FIG. 24 is a graph depicting that the anti-PD-1 J43v2 antibody induced diabetes in NOD mice with increased frequency as dosage increased and that anti-PD-1 J43v2 activatable antibodies exhibited reduced diabetes compared to antibodies at similar doses.
• FIGS. 25A and 25B are a series of graphs depicting the binding to hPD-1 by the anti-PD-1 antibody A1.5 and by of various activatable antibodies of the disclosure comprising the anti-PD1 antibody A1.5, the masking moiety referred to herein as PD34 (SEQ ID NO: 99), and for FIG. 25A, the substrates referred to herein as 2006 (SEQ ID NO: 1095), 2007 (SEQ ID NO: 1096), 2008 (SEQ ID NO: 1097), 2009 (SEQ ID NO: 1098), and 2001 (SEQ ID NO: 214), and for FIG. 25B, the substrates referred to herein as 2001 (SEQ ID NO: 214), 2008 (SEQ ID NO: 1097), 2012 (SEQ ID NO: 1101), 2011 (SEQ ID NO: 1100), and 2003 (SEQ ID NO: 1092).
• FIGS. 26A, 26B, and 26C are a series of graphs depicting the binding to hPD-1 by the anti-PD-1 antibody nivolumab (NV1) and by of various activatable antibodies of the disclosure comprising the anti-PD1 antibody NV1, the substrate referred to herein as 2001 (SEQ ID NO: 214), and the masking moieties referred to herein NV01 (SEQ ID NO: 1206), NV02 (SEQ ID NO: 1207), NV03 (SEQ ID NO: 1208), NV04 (SEQ ID NO: 1209), NV05 (SEQ ID NO: 1210), NV06 (SEQ ID NO: 1211), NV07 (SEQ ID NO: 1212), NV08 (SEQ ID NO: 1213), NV09 (SEQ ID NO: 1214), NV10 (SEQ ID NO: 1215), NV11 (SEQ ID NO: 1216), and NV12 (SEQ ID NO: 1217).
• FIGS. 27A, 27B, and 27C are a series of graphs depicting the binding to hPD-1 by the anti-PD-1 antibody pembrolizumab (PM1) and by various activatable antibodies of the disclosure comprising the anti-PD1 antibody PM1, the substrate referred to herein as 2001 (SEQ ID NO: 214), and the masking moieties referred to herein PM01 (SEQ ID NO: 1351), PM02 (SEQ ID NO: 1352), PM03 (SEQ ID NO: 1353), PM04 (SEQ ID NO: 1354), PM05 (SEQ ID NO: 1355), PM06 (SEQ ID NO: 1356), PM07 (SEQ ID NO: 1357), PM08 (SEQ ID NO: 1358), PM09 (SEQ ID NO: 1359), PM10 (SEQ ID NO: 1360), PM11 (SEQ ID NO: 1361), and PM12 (SEQ ID NO: 1362).
• FIG. 28 is a graph depicting the masking moiety specificity for various activatable antibodies of the disclosure that comprise the anti-PD-1 A1.5 (PD) antibody, the NV1 (NV) antibody, and the PM1 (PM) antibody and a variety of mask and substrate combinations.
• FIGS. 29A and 29B are a series of graphs depicting the binding to PD1 by the IgG2a effector negative (EN) anti-PD1 antibody J43 (J43 m2a EN) and by various activatable antibodies of the disclosure comprising the IgG2a effector negative (EN) anti-PD1 antibody J43 (J43 m2a EN) and a variety of mask and substrate combinations.
• FIG. 30 is a graph depicting that the anti-PD-1 J43m2a EN antibody induced diabetes in NOD mice with increased frequency as dosage increased and that anti-PD-1 J43m2a EN activatable antibodies exhibited reduced diabetes compared to antibodies at similar doses.
• FIGS. 31A and 31B are a series of graphs depicting that anti-PD1 activatable antibodies of the disclosure MP7-1 2001 m2a EN and MP8-2 2001 m2a EN inhibit the growth of MC38 syngeneic tumors in a manner similar to positive control anti-PD1 antibody J43 m2a EN both as single agents (FIG. 31A) and in combination with the commercially available anti-CTLA4 antibody 9D9 mIgG2b (FIG. 31B).
• FIGS. 32A, 32B, 32C, 32D, and 32E are a series of graphs depicting that the anti-human PD1 antibody referred to herein as A1.5 Ab (i.e., VH of SEQ ID NO: 21 and VL of SEQ ID NO: 47) blocks PD-L1/PD-L2 binding to PD1 and potently activates T cells in an antigen recall assay. FIG. 31A shows the binding of the anti-human PD-1 A1.5 Ab to immobilized human PD1 as detected by standard plate ELISA, and FIG. 31B shows the binding of A1.5 Ab to cynomolgus PD1 as detected by ELISA. FIG. 32C depicts the inhibition of biotinylated human PD-L1 to immobilized PD1 by A1.5 Ab as determined by ELISA, and FIG. 32D depicts the inhibition of biotinylated human PD-L2 to immobilized PD1 as determined by ELISA. FIG. 32E demonstrations that the A1.5 Ab enhances IFN-γ production in a CMV T cell restimulation assay.
• FIGS. 33A and 33B are a series of graphs depicting that the activatable anti-PD1 antibody referred to herein as A1.5 PD34 2001 (i.e., VH of SEQ ID NO: 21, VL of SEQ ID NO: 47, masking moiety of SEQ ID NO: 99, and cleavable moiety of SEQ ID NO: 214) binds human PD1 with decreased affinity relative to the parental PD-1 Ab, i.e., A1.5 Ab (FIG. 33A), and the A1.5 PD34 2001 activatable antibody shows functional masking in a CMV T cell antigen recall assay (FIG. 33B).
• FIG. 34 is a graph and a table depicting the results of pharmacokinetic (PK) analysis of plasma samples from cynomolgus monkeys after dosing with a single IV bolus dose of either the A1.5 antibody or the activatable antibody referred to herein as A1.5 PD34 2001 at 1 mg/kg or at 5 mg/kg. Mean PK parameters shown for both A1.5 and A1.5 PD34 2001.
• FIG. 35 is a graph depicting that the combination of 10 mg/kg anti-PD-1 J43 antibody plus 10 mg/kg anti-CTLA-4 antibody dosed on days 0, 4 and 7 induced diabetes in 50% of NOD mice by day eleven while the same dosing schedule of activatable anti-PD-1 J43 antibodies with CTLA-4 antibody resulted in no induction of diabetes to day eighteen.
• FIG. 36 is a graph depicting that the anti-PD1 activatable antibodies MP8-2 2012 m2a EN and MP8-2 2011 m2a EN inhibit the growth of MC38 syngeneic tumors similar to positive control anti-PD1 antibody J43 m2a EN, both as single agents and in combination with anti-CTLA4 antibody 9D9 mIgG2b.
• FIG. 37 is a series of graphs depicting that combination CTLA4 antibody and J43 activatable antibody treatment protects mice against rechallenge with MC38 tumor cells.
• FIG. 38 is a graph depicting that an anti-PD-1 antibody administered alone or in combination with an anti-CTLA4 antibody induced diabetes in NOD mice, whereas an anti-PD-1 activatable antibody as a single agent or in combination with an anti-CTLA4 antibody resulted in no induction of diabetes to day fifteen.
• FIG. 39 is a graph demonstrating that anti-PD-1 activatable A1.5 and activatable nivolumab antibodies of the embodiments enhance IFN-gamma production in a CMV T cell restimulation assay as compared to a control antibody, but not to the extent effected by anti-PD-1 antibody A1.5 or nivolumab.
• FIG. 40 is a graph demonstrating that an anti-PD-1 activatable pembrolizumab antibody of the embodiments enhances IFN-gamma production in a CMV T cell restimulation assay as compared to a control antibody, but not to the extent effected by anti-PD-1 antibody A1.5 or pembrolizumab.
DETAILED DESCRIPTION OF THE INVENTION
• The present invention provides monoclonal antibodies (mAbs), activatable antibodies, and antigen-binding fragments thereof that specifically bind programmed cell death protein 1 (PD-1), also known as CD279. The use of the term “PD-1” is intended to cover any variation thereof, such as, by way of non-limiting example, PD1 and/or PD 1, all variations are used herein interchangeably. Aberrant expression and/or activity of PD-1 and PD-1-related signaling has been implicated in the pathogenesis of many diseases and disorders, such as cancer.
• PD-1, a cell surface receptor that belongs to the immunoglobulin superfamily, is expressed on T cells and pro-B cells. PD-1 is known to bind two ligands, PD-L1 and PD-L2. PD-1 is expressed on the surface of activated T cells, and the interaction between PD-1 and PD-L1 and/or PD-L2 functions as an immune checkpoint, as the binding of PD-L1 or PD-L2 to PD-1 inactivates the T cell. Thus, PD-1 plays a role in down-regulating the immune system by preventing the activation of T-cells, which, in turn, reduces autoimmunity and promotes self-tolerance.
• The anti-PD-1 monoclonal antibodies and activated activatable anti-PD-1 antibodies of the disclosure bind and neutralize or otherwise inhibit the ability of PD-1 to bind or otherwise interact with PD-L1 and/or PD-L2. The anti-PD-1 monoclonal antibodies and activated activatable anti-PD-1 antibodies of the disclosure bind and neutralize or otherwise inhibit at least one biological activity of PD-1. For example, the anti-PD-1 monoclonal antibodies and activated activatable anti-PD-1 antibodies of the disclosure bind PD-1 and block or otherwise inhibit ligand activation of PD-1 on activated T cells. In contrast to traditional chemotherapies and other targeted anti-cancer therapies, which exert their effects by direct cytotoxic or tumor growth inhibition, the monoclonal antibodies and activatable antibodies of the disclosure block a negative regulator of T-cell activation and response, thereby allowing the immune system to attack the tumor.
• The activatable anti-PD-1 antibodies of the disclosure include an antibody or antigen-binding fragment thereof that specifically binds PD-1 coupled to a masking moiety (MM), such that coupling of the MM reduces the ability of the antibody or antigen-binding fragment thereof to bind PD-1. The MM is coupled via a cleavable moiety (CM) that includes a sequence that functions as a substrate for a protease.
• The activatable anti-PD-1 antibodies of the disclosure are activated when the cleavable moiety is cleaved by a protease. For example, the protease is produced by a tumor that is in proximity to T cells that express PD-1. In some embodiments, the protease is produced by a tumor that is co-localized with T cells that express PD-1. In the activated, i.e., cleaved state, the activatable anti-PD-1 antibodies of the disclosure bind PD-1 expressed on a T cell surface.
• The activatable anti-PD-1 antibodies are used in methods of treating, preventing, delaying the progression of, ameliorating and/or alleviating a symptom of a disease or disorder associated with binding of a ligand selected from the group consisting of PD-L1 and PD-L2 to PD-1 on a T cell. Such ligands are often found on tumor cells and other immune cells. Binding of such ligands to PD-1 can lead to immune suppression, such as suppression of T cell activity, which is reduced by anti-PD1 antibodies and activatable anti-PD-1 antibodies of the disclosure. For example, the activatable anti-PD-1 antibodies are used in methods of treating, preventing, delaying the progression of, ameliorating and/or alleviating a symptom of a cancer or other neoplastic condition.
• Exemplary activatable anti-PD-1 antibodies of the invention include, for example, activatable antibodies that include a heavy chain and a light chain that are, or are derived from, antibodies described in the Examples, for example in Examples 1, 2, 8, 9, 14, and 15.
• In some embodiments, the activatable anti-PD-1 antibody includes a heavy chain that comprises or is derived from an amino acid sequence selected from the group consisting of SEQ ID NO: 1, 5, 9, 13, 17, 21, 23, 25, 27, 29, 31, 33, 35, and 37, and a light chain that comprises or is derived from an amino acid sequence selected from the group consisting of SEQ ID NO: 3, 7, 11, 15, 19, 39, 41, 43, 45, 47, 49, 51, 53, 55, 57, 59, 215, 217, 219, 221, 223, 225, 227, 229, 231, 233, 235, 237, 239, 241, 245, 247, 249, 251, 253, 255, 257, 259, 261, 263, 265, 267, 269, 271, 273, 275, 277, 279, 281, 283, 285, 287, 289, 291, 293, 515, 517, 519, 521, 523, 525, 527, 529, 531, 533, 535, 537, 539, 541, 572, 574, 576, 578, 580, 582, 919, 921, 923, 925, 927, 929, 931, 933, 935, 937, 939, 941, 943, 945, 947, 949, 951, 953, 955, 957, 959, 961, 963, 965, 967, 969, 971, 973, 975, 977, 979, 981, 983, 985, 987, 989, 991, 993, 995, 997, 999, 1001, 1003, 1005, 1007, 1009, 1011, 1013, 1015, 1017, 1019, 1021, 1023, 1025, 1027, 1030, 1032, 1034, 1036, 1039, 1041-1090, 1113-1120, 1123, 1124, 1127, 1128, 1131, 1132, 1134, 1135, 1138, 1139, 1143, 1144, 1147, 1148, 1151, 1152, 1155, 1156, 1159, 1160, 1163, 1164, 1167, 1168, 1170, 1171, 1174, 1175, 1178, 1179, 1182, 1183, 1186, 1187, 1190, 1191, 1194, 1195, 1198, 1199, 1202, 1203, 2055, 2054, 2057, 2056, 2059, and 2058.
• In some embodiments, the activatable anti-PD-1 antibody includes a heavy chain that comprises or is derived from an amino acid sequence selected from the group consisting of SEQ ID NO: 21, 23, 25, 27, 29, 31, 33, 35, and 37, and a light chain that comprises or is derived from an amino acid sequence selected from the group consisting of SEQ ID NO: 39, 41, 43, 45, 47, 49, 51, 53, 55, 57, 59, 215, 217, 219, 221, 223, 225, 227, 229, 231, 233, 235, 237, 239, 241, 245, 247, 249, 251, 253, 255, 257, 259, 261, 263, 265, 267, 269, 271, 273, 275, 277, 279, 281, 283, 285, 287, 289, 291, 293, 515, 517, 519, 521, 523, 525, 527, 529, 531, 533, 535, 537, 539, 541, 572, 574, 576, 578, 580, 582, 584, 919, 921, 923, 925, 927, 929, 931, 933, 935, 937, 939, 941, 943, 945, 947, 949, 951, 953, 955, 957, 959, 961, 963, 965, 967, 969, 971, 973, 975, 977, 979, 981, 983, 985, 987, 989, 991, 993, 995, 997, 999, 1001, 1003, 1005, 1007, 1009, 1011, 1013, 1015, 1017, 1019, 1021, 1023, 1025, 1027, 1029, 1030, 1032, 1034, 1036, 1039, 1041-1090, 1113-1120, 1123, 1127, 1131, 1134, 1138, 1144, 1148, 1152, 1156, 1160, 1164, 1168, 1170, 1174, 1178, 1182, 1186, 1190, 1194, 1198, 1203, 2055, 2054, 2057, 2056, 2059, and 2058.
• In some embodiments, the light chain comprises or is derived from an amino acid sequence selected from the group consisting of SEQ ID NO: 39, 41, 43, 45, 47, 49, 51, 53, 55, 57, and 59. In some embodiments, the light chain comprises or is derived from an amino acid sequence selected from the group consisting of SEQ ID NO: 215, 217, 219, 221, 223, 225, 227, 229, 231, 233, 235, 237, 239, 241, 245, 247, 249, 251, 253, 255, 257, 259, 261, 263, 265, 267, 269, 271, 273, 275, 277, 279, 281, 283, 285, 287, 289, 291, 293, 584, 919, 921, 923, 925, 927, 929, 931, 933, 935, 937, 939, 941, 943, 945, 947, 949, 951, 953, 955, 957, 959, 961, 963, 965, 967, 969, 971, 973, 975, 977, 979, 981, 983, 985, 987, 989, 991, 993, 995, and 997.
• In some embodiments, the activatable anti-PD-1 antibody includes a heavy chain that comprises or is derived from an amino acid sequence selected from the group consisting of SEQ ID NO: 21, 23, 25, 27, 29, 31, 33, 35, and 37, and a light chain that comprises or is derived from an amino acid sequence selected from the group consisting of 215, 217, 219, 221, 223, 225, 227, 229, 231, 233, 235, 237, 239, 241, 243, 245, 247, 249, 251, 253, 255, 257, 259, 261, 263, 265, 267, 269, 271, 273, 275, 277, 279, 281, 283, 285, 287, 289, 291, 293, 572, 574, 576, 578, 580, 582, 1029, 1120, 1124, 1128, 1132, 1135, 1139, 1143, 1147, 1151, 1155, 1159, 1163, 1167, 1171, 1175, 1179, 1183, 1187, 1191, 1195, 1199, 1203, 2055, 2054, 2057, 2056, 2059, and 2058.
• In some embodiments, the light chain comprises or is derived from an amino acid sequence selected from the group consisting of SEQ ID NO: 515, 517, 519, 521, 523, 525, 527, 529, 531, 533, 535, 537, 539, 541, 572, 574, 576, 578, 580, 582, 999, 1001, 1003, 1005, 1007, 1009, 1011, 1013, 1015, 1017, 1019, 1021, 1023, 1025, 1027, 1029, 1030, 1032, 1034, 1036, 1039, 1041-1090, 1113-1120, 1123, 1127, 1131, 1134, 1138, 1144, 1148, 1152, 1156, 1160, 1164, 1168, 1170, 1174, 1178, 1182, 1186, 1190, 1194, 1198, 1203, 2055, 2054, 2057, 2056, 2059, and 2058.
• In some embodiments, the activatable anti-PD-1 antibody includes a light chain that comprises or is derived from an amino acid sequence selected from the group consisting of SEQ ID NOs: 215, 217, 219, 221, 223, 225, 227, 229, 231, 233, 235, 237, 239, 241, 243, 245, 247, 249, 251, 253, 255, 257, 259, 261, 263, 265, 267, 269, 271, 273, 275, 277, 279, 281, 283, 285, 287, 289, 291, 293, 515, 517, 519, 521, 523, 525, 527, 529, 531, 533, 535, 537, 539, 541, 572, 574, 576, 578, 580, 582, 919, 921, 923, 925, 927, 929, 931, 933, 935, 937, 939, 941, 943, 945, 947, 949, 951, 953, 955, 957, 959, 961, 963, 965, 967, 969, 971, 973, 975, 977, 979, 981, 983, 985, 987, 989, 991, 993, 995, 997, 1027, 1028, 1029, 1030, 1032, 1034, 1036, 1039, 1041-1076, 1113-1120, 1123, 1124, 1127, 1128, 1131, 1132, 1134, 1135, 1138, 1139, 1143, 1144, 1147, 1148, 1151, 1152, 1155, 1156, 1159, 1160, 1163, 1164, 1167, 1168, 1170, 1171, 1174, 1175, 1178, 1179, 1182, 1183, 1186, 1187, 1190, 1191, 1194, 1195, 1198, 1199, 1202, 12032055, 2054, 2057, 2056, 2059, and 2058.
• In some embodiments, the activatable anti-PD-1 antibody includes a heavy chain that comprises or is derived from an amino acid sequence selected from the group consisting of SEQ ID NO: 21, 23, 25, 27, 29, 31, 33, 35, and 37, and a light chain that comprises or is derived from an amino acid sequence selected from the group consisting of SEQ ID NOs: 215, 217, 219, 221, 223, 225, 227, 229, 231, 233, 235, 237, 239, 241, 243, 245, 247, 249, 251, 253, 255, 257, 259, 261, 263, 265, 267, 269, 271, 273, 275, 277, 279, 281, 283, 285, 287, 289, 291, 293, 919, 921, 923, 925, 927, 929, 931, 933, 935, 937, 939, 941, 943, 945, 947, 949, 951, 953, 955, 957, 959, 961, 963, 965, 967, 969, 971, 973, 975, 977, 979, 981, 983, 985, 987, 989, 991, 993, 995, 997, 1028, 1029, 1041-1076, 1138, 1139, 1143, 1144, 1147, 1148, 1151, 1152, 1155, 1156, 1159, 1160, 1163, 1164, 1167, 1168, 1170, 1171, 1174, 1175, 1178, 1179, 1182, 1183, 1186, 1187, 1190, 1191, 1194, 1195, 1198, 1199, 1202, 1203, 2055, 2054, 2057, 2056, 2059, and 2058.
• In some embodiments, the light chain comprises or is derived from an amino acid sequence selected from the group consisting of SEQ ID NOs: 919, 921, 923, 925, 927, 929, 931, 933, 935, 937, 939, 941, 943, 945, 947, 949, 951, 953, 955, 957, 959, 961, 963, 965, 967, 969, 971, 973, 975, 977, 979, 981, 983, 985, 987, 989, 991, 993, 995, 997, 1028, 1041-1076, 1138, 1144, 1148, 1152, 1156, 1160, 1164, 1168, 1170, 1174, 1178, 1182, 1186, 1190, 1194, 1198, 1202, 2055, 2057, and 2059.
• In some embodiments, the light chain comprises or is derived from an amino acid sequence selected from the group consisting of SEQ ID NOs: 215, 217, 219, 221, 223, 225, 227, 229, 231, 233, 235, 237, 239, 241, 243, 245, 247, 249, 251, 253, 255, 257, 259, 261, 263, 265, 267, 269, 271, 273, 275, 277, 279, 281, 283, 285, 287, 289, 291, 293, 1029, 1139, 1143, 1147, 1151, 1155, 1159, 1163, 1167, 1171, 1175, 1179, 1183, 1187, 1191, 1195, 1199, 1203, 2054, 2056, and 2058.
• In some embodiments, the activatable anti-PD-1 antibody includes a heavy chain that comprises or is derived from an amino acid sequence selected from the group consisting of SEQ ID NO: 546 and a light chain that comprises or is derived from an amino acid sequence selected from the group consisting of SEQ ID NOs: 515, 517, 519, 521, 523, 525, 527, 529, 531, 533, 535, 537, 539, 541, 572, 574, 576, 578, 580, 582, 999, 1001, 1003, 1005, 1007, 1009, 1011, 1013, 1015, 1017, 1019, 1021, 1023, 1025, 1027, 1030, 1032, 1034, 1036, 1039, 1077-1090, 1113-1120, 1123, 1124, 1127, 1128, 1131, 1132, 1134, and 1135.
• In some embodiments, the activatable anti-PD-1 antibody includes a light chain that comprises or is derived from an amino acid sequence selected from the group consisting of SEQ ID NOS: 999, 1001, 1003, 1005, 1007, 1009, 1011, 1013, 1015, 1017, 1019, 1021, 1023, 1025, 1027, 1030, 1032, 1034, 1036, 1039, 1070-1090, 1119, 1123, 1127, 1131, and 1134.
• In some embodiments, the activatable anti-PD-1 antibody includes a light chain that comprises or is derived from an amino acid sequence selected from the group consisting of SEQ ID NOS: 515, 517, 519, 521, 523, 525, 527, 529, 531, 533, 535, 537, 539, 541, 572, 574, 576, 578, 580, 582, 1120, 1124, 1128, 1132, and 1135.
• In some embodiments, the activatable anti-PD-1 antibody includes a heavy chain that comprises or is derived from a heavy chain amino acid sequence shown in Table 7. In some embodiments, the activatable anti-PD-1 antibody includes a light chain that comprises or is derived from a light chain amino acid sequence shown in Table 7. In some embodiments, the activatable anti-PD-1 antibody includes a heavy chain that comprises or is derived from a heavy chain amino acid sequence shown in Table 7, and a light chain that comprises or is derived from a light chain amino acid sequence shown in Table 7. In some embodiments, the activatable anti-PD-1 antibody includes a combination of a heavy chain variable region sequence and a light chain variable region sequence from the combinations shown in Group A in Table 7. In some embodiments, the activatable anti-PD-1 antibody includes a combination of a heavy chain variable region sequence and a light chain variable region sequence from the combinations shown in Group B in Table 7. In some embodiments, the activatable anti-PD-1 antibody includes a combination of a heavy chain variable region sequence and a light chain variable region sequence from the combinations shown in Group C in Table 7. In some embodiments, the activatable anti-PD-1 antibody includes a combination of a heavy chain variable region sequence and a light chain variable region sequence from the combinations shown in Group D in Table 7. In some embodiments, the activatable anti-PD-1 antibody includes a combination of a heavy chain variable region sequence and a light chain variable region sequence from the combinations shown in Group E in Table 7. In some embodiments, the activatable anti-PD-1 antibody includes a combination of a heavy chain variable region sequence and a light chain variable region sequence from the combinations shown in Group F in Table 7. In some embodiments, the activatable anti-PD-1 antibody includes a combination of a heavy chain variable region sequence and a light chain variable region sequence from the combinations shown in Group H in Table 7. In some embodiments, the activatable anti-PD-1 antibody includes a combination of a heavy chain variable region sequence and a light chain variable region sequence from the combinations shown in Group I in Table 7. In some embodiments, the activatable anti-PD-1 antibody includes a combination of a heavy chain variable region sequence and a light chain variable region sequence from the combinations shown in Group J in Table 7. In some embodiments, the activatable anti-PD-1 antibody includes a combination of a heavy chain variable region sequence and a light chain variable region sequence from the combinations shown in Group K in Table 7. In some embodiments, the activatable anti-PD-1 antibody includes a combination of a heavy chain variable region sequence and a light chain variable region sequence from the combinations shown in Group L in Table 7. In some embodiments, the activatable anti-PD-1 antibody includes a combination of a heavy chain variable region sequence and a light chain variable region sequence from the combinations shown in Group M in Table 7. In some embodiments, the activatable anti-PD-1 antibody includes a combination of the heavy chain variable region sequence and the light chain variable region sequence as shown in Group N in Table 7. In some embodiments, the activatable anti-PD-1 antibody includes a combination of the heavy chain variable region sequence and the light chain variable region sequence as shown in Group O in Table 7. In some embodiments, the activatable anti-PD-1 antibody includes a combination of a heavy chain variable region sequence and a light chain variable region sequence from the combinations shown in Group P in Table 7. In some embodiments, the activatable anti-PD-1 antibody includes a combination of a heavy chain variable region sequence and a light chain variable region sequence from the combinations shown in Group Q in Table 7.
• In some embodiments, the activatable anti-PD-1 antibody includes a combination of the complementarity determining region (CDR) sequences of a heavy chain sequence from the heavy chain sequences shown in Group A in Table 7. In some embodiments, the activatable anti-PD-1 antibody includes a combination of the CDRs of a light chain sequence from the light chain sequences shown in Group A in Table 7. In some embodiments, the activatable anti-PD-1 antibody includes a combination of the CDRs of a heavy chain sequence from the heavy chain sequences shown in Group A in Table 7 and the CDRs of a light chain sequence from the heavy chain sequences shown in Group A in Table 7.
• In some embodiments, the activatable anti-PD-1 antibody includes a combination of CDRs of a heavy chain sequence from the heavy chain sequences shown in Group B in Table 7. In some embodiments, the activatable anti-PD-1 antibody includes a combination of the CDRs of a light chain sequence from the light chain sequences shown in Group B in Table 7. In some embodiments, the activatable anti-PD-1 antibody includes a combination of the CDRs of a heavy chain sequence from the heavy chain sequences shown in Group B in Table 7 and the CDRs of a light chain sequence from the heavy chain sequences shown in Group B in Table 7.
• In some embodiments, the activatable anti-PD-1 antibody includes a combination of the CDRs of a heavy chain sequence from the heavy chain sequences shown in Group C in Table 7. In some embodiments, the activatable anti-PD-1 antibody includes a combination of the CDRs of a light chain sequence from the light chain sequences shown in Group C in Table 7. In some embodiments, the activatable anti-PD-1 antibody includes a combination of the CDRs of a heavy chain sequence from the heavy chain sequences shown in Group C in Table 7 and the CDRs of a light chain sequence from the heavy chain sequences shown in Group C in Table 7.
• In some embodiments, the activatable anti-PD-1 antibody includes a combination of the CDRs of a heavy chain sequence from the heavy chain sequences shown in Group D in Table 7. In some embodiments, the activatable anti-PD-1 antibody includes a combination of the CDRs of a light chain sequence from the light chain sequences shown in Group D in Table 7. In some embodiments, the activatable anti-PD-1 antibody includes a combination of the CDRs of a heavy chain sequence from the heavy chain sequences shown in Group D in Table 7 and the CDRs of a light chain sequence from the heavy chain sequences shown in Group D in Table 7.
• In some embodiments, the activatable anti-PD-1 antibody includes a combination of the CDRs of a heavy chain sequence from the heavy chain sequences shown in Group E in Table 7. In some embodiments, the activatable anti-PD-1 antibody includes a combination of the CDRs of a light chain sequence from the light chain sequences shown in Group E in Table 7. In some embodiments, the activatable anti-PD-1 antibody includes a combination of the CDRs of a heavy chain sequence from the heavy chain sequences shown in Group E in Table 7 and the CDRs of a light chain sequence from the heavy chain sequences shown in Group E in Table 7.
• In some embodiments, the activatable anti-PD-1 antibody includes a combination of the CDRs of a heavy chain sequence from the heavy chain sequences shown in Group F in Table 7. In some embodiments, the activatable anti-PD-1 antibody includes a combination of the CDRs of a light chain sequence from the light chain sequences shown in Group F in Table 7. In some embodiments, the activatable anti-PD-1 antibody includes a combination of the CDRs of a heavy chain sequence from the heavy chain sequences shown in Group F in Table 7 and the CDRs of a light chain sequence from the heavy chain sequences shown in Group F in Table 7.
• In some embodiments, the activatable anti-PD-1 antibody includes a combination of the CDRs of a heavy chain sequence from the heavy chain sequences shown in Group G in Table 7. In some embodiments, the activatable anti-PD-1 antibody includes a combination of the CDRs of a light chain sequence from the light chain sequences shown in Group G in Table 7. In some embodiments, the activatable anti-PD-1 antibody includes a combination of the CDRs of a heavy chain sequence from the heavy chain sequences shown in Group G in Table 7 and the CDRs of a light chain sequence from the heavy chain sequences shown in Group G in Table 7.
• In some embodiments, the activatable anti-PD-1 antibody includes a combination of the CDRs of a heavy chain sequence from the heavy chain sequences shown in Group H in Table 7. In some embodiments, the activatable anti-PD-1 antibody includes a combination of the CDRs of a light chain sequence from the light chain sequences shown in Group H in Table 7. In some embodiments, the activatable anti-PD-1 antibody includes a combination of the CDRs of a heavy chain sequence from the heavy chain sequences shown in Group H in Table 7 and the CDRs of a light chain sequence from the heavy chain sequences shown in Group H in Table 7.
• In some embodiments, the activatable anti-PD-1 antibody includes a combination of the CDRs of a heavy chain sequence from the heavy chain sequences shown in Group I in Table 7. In some embodiments, the activatable anti-PD-1 antibody includes a combination of the CDRs of a light chain sequence from the light chain sequences shown in Group I in Table 7. In some embodiments, the activatable anti-PD-1 antibody includes a combination of the CDRs of a heavy chain sequence from the heavy chain sequences shown in Group I in Table 7 and the CDRs of a light chain sequence from the heavy chain sequences shown in Group I in Table 7.
• In some embodiments, the activatable anti-PD-1 antibody includes a combination of the CDRs of a heavy chain sequence from the heavy chain sequences shown in Group J in Table 7. In some embodiments, the activatable anti-PD-1 antibody includes a combination of the CDRs of a light chain sequence from the light chain sequences shown in Group J in Table 7. In some embodiments, the activatable anti-PD-1 antibody includes a combination of the CDRs of a heavy chain sequence from the heavy chain sequences shown in Group J in Table 7 and the CDRs of a light chain sequence from the heavy chain sequences shown in Group J in Table 7.
• In some embodiments, the activatable anti-PD-1 antibody includes a combination of the CDRs of a heavy chain sequence from the heavy chain sequences shown in Group K in Table 7. In some embodiments, the activatable anti-PD-1 antibody includes a combination of the CDRs of a light chain sequence from the light chain sequences shown in Group K in Table 7. In some embodiments, the activatable anti-PD-1 antibody includes a combination of the CDRs of a heavy chain sequence from the heavy chain sequences shown in Group K in Table 7 and the CDRs of a light chain sequence from the heavy chain sequences shown in Group K in Table 7.
• In some embodiments, the activatable anti-PD-1 antibody includes a combination of the CDRs of a heavy chain sequence from the heavy chain sequences shown in Group L in Table 7. In some embodiments, the activatable anti-PD-1 antibody includes a combination of the CDRs of a light chain sequence from the light chain sequences shown in Group L in Table 7. In some embodiments, the activatable anti-PD-1 antibody includes a combination of the CDRs of a heavy chain sequence from the heavy chain sequences shown in Group L in Table 7 and the CDRs of a light chain sequence from the heavy chain sequences shown in Group L in Table 7.
• In some embodiments, the activatable anti-PD-1 antibody includes a combination of the CDRs of a heavy chain sequence from the heavy chain sequences shown in Group M in Table 7. In some embodiments, the activatable anti-PD-1 antibody includes a combination of the CDRs of a light chain sequence from the light chain sequences shown in Group M in Table 7. In some embodiments, the activatable anti-PD-1 antibody includes a combination of the CDRs of a heavy chain sequence from the heavy chain sequences shown in Group M in Table 7 and the CDRs of a light chain sequence from the heavy chain sequences shown in Group M in Table 7.
• In some embodiments, the activatable anti-PD-1 antibody includes a combination of the CDRs of a heavy chain sequence from the heavy chain sequences shown in Group N in Table 7. In some embodiments, the activatable anti-PD-1 antibody includes a combination of the CDRs of a light chain sequence from the light chain sequences shown in Group N in Table 7. In some embodiments, the activatable anti-PD-1 antibody includes a combination of the CDRs of a heavy chain sequence from the heavy chain sequences shown in Group N in Table 7 and the CDRs of a light chain sequence from the heavy chain sequences shown in Group N in Table 7.
• In some embodiments, the activatable anti-PD-1 antibody includes a combination of the CDRs of a heavy chain sequence from the heavy chain sequences shown in Group O in Table 7. In some embodiments, the activatable anti-PD-1 antibody includes a combination of the CDRs of a light chain sequence from the light chain sequences shown in Group O in Table 7. In some embodiments, the activatable anti-PD-1 antibody includes a combination of the CDRs of a heavy chain sequence from the heavy chain sequences shown in Group O in Table 7 and the CDRs of a light chain sequence from the heavy chain sequences shown in Group O in Table 7.
• In some embodiments, the activatable anti-PD-1 antibody includes a combination of the CDRs of a heavy chain sequence from the heavy chain sequences shown in Group P in Table 7. In some embodiments, the activatable anti-PD-1 antibody includes a combination of the CDRs of a light chain sequence from the light chain sequences shown in Group P in Table 7. In some embodiments, the activatable anti-PD-1 antibody includes a combination of the CDRs of a heavy chain sequence from the heavy chain sequences shown in Group P in Table 7 and the CDRs of a light chain sequence from the heavy chain sequences shown in Group P in Table 7.
• In some embodiments, the activatable anti-PD-1 antibody includes a combination of the CDRs of a heavy chain sequence from the heavy chain sequences shown in Group Q in Table 7. In some embodiments, the activatable anti-PD-1 antibody includes a combination of the CDRs of a light chain sequence from the light chain sequences shown in Group Q in Table 7. In some embodiments, the activatable anti-PD-1 antibody includes a combination of the CDRs of a heavy chain sequence from the heavy chain sequences shown in Group Q in Table 7 and the CDRs of a light chain sequence from the heavy chain sequences shown in Group Q in Table 7.
• In some embodiments, the activatable anti-PD-1 antibody includes a combination of the CDRs of a heavy chain sequence from the heavy chain sequences shown in Group R in Table 7. In some embodiments, the activatable anti-PD-1 antibody includes a combination of the CDRs of a light chain sequence from the light chain sequences shown in Group R in Table 7. In some embodiments, the activatable anti-PD-1 antibody includes a combination of the CDRs of a heavy chain sequence from the heavy chain sequences shown in Group R in Table 7 and the CDRs of a light chain sequence from the heavy chain sequences shown in Group R in Table 7.
• In some embodiments, the activatable anti-PD-1 antibody includes a combination of the CDRs of a heavy chain sequence from the heavy chain sequences shown in Group S in Table 7. In some embodiments, the activatable anti-PD-1 antibody includes a combination of the CDRs of a light chain sequence from the light chain sequences shown in Group S in Table 7. In some embodiments, the activatable anti-PD-1 antibody includes a combination of the CDRs of a heavy chain sequence from the heavy chain sequences shown in Group S in Table 7 and the CDRs of a light chain sequence from the heavy chain sequences shown in Group S in Table 7.
• In some embodiments, the activatable anti-PD-1 antibody includes a combination of the CDRs of a heavy chain sequence from the heavy chain sequences shown in Group T in Table 7. In some embodiments, the activatable anti-PD-1 antibody includes a combination of the CDRs of a light chain sequence from the light chain sequences shown in Group T in Table 7. In some embodiments, the activatable anti-PD-1 antibody includes a combination of the CDRs of a heavy chain sequence from the heavy chain sequences shown in Group T in Table 7 and the CDRs of a light chain sequence from the heavy chain sequences shown in Group T in Table 7.
• In some embodiments, the activatable anti-PD-1 antibody includes a combination of the CDRs of a heavy chain sequence from the heavy chain sequences shown in Group U in Table 7. In some embodiments, the activatable anti-PD-1 antibody includes a combination of the CDRs of a light chain sequence from the light chain sequences shown in Group U in Table 7. In some embodiments, the activatable anti-PD-1 antibody includes a combination of the CDRs of a heavy chain sequence from the heavy chain sequences shown in Group U in Table 7 and the CDRs of a light chain sequence from the heavy chain sequences shown in Group U in Table 7.
• In some embodiments, the activatable anti-PD-1 antibody includes a combination of the CDRs of a heavy chain sequence from the heavy chain sequences shown in Group V in Table 7. In some embodiments, the activatable anti-PD-1 antibody includes a combination of the CDRs of a light chain sequence from the light chain sequences shown in Group V in Table 7. In some embodiments, the activatable anti-PD-1 antibody includes a combination of the CDRs of a heavy chain sequence from the heavy chain sequences shown in Group V in Table 7 and the CDRs of a light chain sequence from the heavy chain sequences shown in Group V in Table 7.
• In some embodiments, the activatable anti-PD-1 antibody includes a combination of the CDRs of the heavy chain sequence of SEQ ID NO: 619 and a combination of the CDRs of the light chain sequence of SEQ ID NO: 1856 as shown in Group V in Table 7. In some embodiments, the activatable anti-PD-1 antibody includes a combination of the heavy chain sequence of SEQ ID NO: 619 and the light chain sequence of SEQ ID NO: 1856 as shown in Group V in Table 7.
• In some embodiments, the activatable anti-PD-1 antibody includes a combination of the CDRs of the heavy chain sequence of SEQ ID NO: 1846 and a combination of the CDRs of the light chain sequence of SEQ ID NO: 1858 as shown in Group V in Table 7. In some embodiments, the activatable anti-PD-1 antibody includes a combination of the heavy chain sequence of SEQ ID NO: 1846 and the light chain sequence of SEQ ID NO: 1858 as shown in Group V in Table 7.
• In some embodiments, the activatable anti-PD-1 antibody includes a combination of the CDRs of the heavy chain sequence of SEQ ID NO: 1843 and a combination of the CDRs of the light chain sequence of SEQ ID NO: 1859 as shown in Group V in Table 7. In some embodiments, the activatable anti-PD-1 antibody includes a combination of the heavy chain sequence of SEQ ID NO: 1843 and the light chain sequence of SEQ ID NO: 1859 as shown in Group V in Table 7.
• In some embodiments, the activatable anti-PD-1 antibody includes a combination of the CDRs of the heavy chain sequence of SEQ ID NO: 1847 and a combination of the CDRs of the light chain sequence of SEQ ID NO: 737 as shown in Group V in Table 7. In some embodiments, the activatable anti-PD-1 antibody includes a combination of the heavy chain sequence of SEQ ID NO: 1847 and the light chain sequence of SEQ ID NO: 737 as shown in Group V in Table 7.
• In some embodiments, the activatable anti-PD-1 antibody includes a combination of the CDRs of the heavy chain sequence of SEQ ID NO: 1848 and a combination of the CDRs of the light chain sequence of SEQ ID NO: 1860 as shown in Group V in Table 7. In some embodiments, the activatable anti-PD-1 antibody includes a combination of the heavy chain sequence of SEQ ID NO: 1848 and the light chain sequence of SEQ ID NO: 1860 as shown in Group V in Table 7.
• In some embodiments, the activatable anti-PD-1 antibody includes a combination of the CDRs of the heavy chain sequence of SEQ ID NO: 1844 and a combination of the CDRs of the light chain sequence of SEQ ID NO: 1861 as shown in Group V in Table 7. In some embodiments, the activatable anti-PD-1 antibody includes a combination of the heavy chain sequence of SEQ ID NO: 1844 and the light chain sequence of SEQ ID NO: 1861 as shown in Group V in Table 7.
• In some embodiments, the activatable anti-PD-1 antibody includes a combination of the CDRs of the heavy chain sequence of SEQ ID NO: 1841 and a combination of the CDRs of the light chain sequence of SEQ ID NO: 737 as shown in Group V in Table 7. In some embodiments, the activatable anti-PD-1 antibody includes a combination of the heavy chain sequence of SEQ ID NO: 1841 and the light chain sequence of SEQ ID NO: 737 as shown in Group V in Table 7.
• In some embodiments, the activatable anti-PD-1 antibody includes a combination of the CDRs of the heavy chain sequence of SEQ ID NO: 1842 and a combination of the CDRs of the light chain sequence of SEQ ID NO: 737 as shown in Group V in Table 7. In some embodiments, the activatable anti-PD-1 antibody includes a combination of the heavy chain sequence of SEQ ID NO: 1842 and the light chain sequence of SEQ ID NO: 737 as shown in Group V in Table 7.
• In some embodiments, the activatable anti-PD-1 antibody includes a combination of the CDRs of the heavy chain sequence of SEQ ID NO: 1845 and a combination of the CDRs of the light chain sequence of SEQ ID NO: 737 as shown in Group V in Table 7. In some embodiments, the activatable anti-PD-1 antibody includes a combination of the heavy chain sequence of SEQ ID NO: 1845 and the light chain sequence of SEQ ID NO: 737 as shown in Group V in Table 7.
• In some embodiments, the activatable anti-PD-1 antibody includes a combination of the CDRs of the heavy chain sequence of SEQ ID NO: 1835 and a combination of the CDRs of the light chain sequence of SEQ ID NO: 1857 as shown in Group V in Table 7. In some embodiments, the activatable anti-PD-1 antibody includes a combination of the heavy chain sequence of SEQ ID NO: 1835 and the light chain sequence of SEQ ID NO: 1857 as shown in Group V in Table 7.
• In some embodiments, the activatable anti-PD-1 antibody includes a combination of the CDRs of the heavy chain sequence of SEQ ID NO: 1836 and a combination of the CDRs of the light chain sequence of SEQ ID NO: 1862 as shown in Group V in Table 7. In some embodiments, the activatable anti-PD-1 antibody includes a combination of the heavy chain sequence of SEQ ID NO: 1836 and the light chain sequence of SEQ ID NO: 1862 as shown in Group V in Table 7.
• In some embodiments, the activatable anti-PD-1 antibody includes a combination of the CDRs of the heavy chain sequence of SEQ ID NO: 1837 and a combination of the CDRs of the light chain sequence of SEQ ID NO: 1863 as shown in Group V in Table 7. In some embodiments, the activatable anti-PD-1 antibody includes a combination of the heavy chain sequence of SEQ ID NO: 1837 and the light chain sequence of SEQ ID NO: 1863 as shown in Group V in Table 7.
• In some embodiments, the activatable anti-PD-1 antibody includes a combination of the CDRs of the heavy chain sequence of SEQ ID NO: 1838 and a combination of the CDRs of the light chain sequence of SEQ ID NO: 1864 as shown in Group V in Table 7. In some embodiments, the activatable anti-PD-1 antibody includes a combination of the heavy chain sequence of SEQ ID NO: 1838 and the light chain sequence of SEQ ID NO: 1864 as shown in Group V in Table 7.
• In some embodiments, the activatable anti-PD-1 antibody includes a combination of the CDRs of the heavy chain sequence of SEQ ID NO: 1838 and a combination of the CDRs of the light chain sequence of SEQ ID NO: 1865 as shown in Group V in Table 7. In some embodiments, the activatable anti-PD-1 antibody includes a combination of the heavy chain sequence of SEQ ID NO: 1838 and the light chain sequence of SEQ ID NO: 1865 as shown in Group V in Table 7.
• In some embodiments, the activatable anti-PD-1 antibody includes a combination of the CDRs of the heavy chain sequence of SEQ ID NO: 1839 and a combination of the CDRs of the light chain sequence of SEQ ID NO: 1864 as shown in Group V in Table 7. In some embodiments, the activatable anti-PD-1 antibody includes a combination of the heavy chain sequence of SEQ ID NO: 1839 and the light chain sequence of SEQ ID NO: 1864 as shown in Group V in Table 7.
• In some embodiments, the activatable anti-PD-1 antibody includes a combination of the CDRs of the heavy chain sequence of SEQ ID NO: 1839 and a combination of the CDRs of the light chain sequence of SEQ ID NO: 1865 as shown in Group V in Table 7. In some embodiments, the activatable anti-PD-1 antibody includes a combination of the heavy chain sequence of SEQ ID NO: 1839 and the light chain sequence of SEQ ID NO: 1865 as shown in Group V in Table 7.
• In some embodiments, the activatable anti-PD-1 antibody includes a combination of the CDRs of the heavy chain sequence of SEQ ID NO: 1840 and a combination of the CDRs of the light chain sequence of SEQ ID NO: 1866 as shown in Group V in Table 7. In some embodiments, the activatable anti-PD-1 antibody includes a combination of the heavy chain sequence of SEQ ID NO: 1840 and the light chain sequence of SEQ ID NO: 1866 as shown in Group V in Table 7.
• In some embodiments, the activatable anti-PD-1 antibody includes a combination of the CDRs of the heavy chain sequence of SEQ ID NO: 1841 and a combination of the CDRs of the light chain sequence of SEQ ID NO: 1867 as shown in Group V in Table 7. In some embodiments, the activatable anti-PD-1 antibody includes a combination of the heavy chain sequence of SEQ ID NO: 1841 and the light chain sequence of SEQ ID NO: 1867 as shown in Group V in Table 7.
• In some embodiments, the activatable anti-PD-1 antibody includes a combination of the CDRs of the heavy chain sequence of SEQ ID NO: 1841 and a combination of the CDRs of the light chain sequence of SEQ ID NO: 1868 as shown in Group V in Table 7. In some embodiments, the activatable anti-PD-1 antibody includes a combination of the heavy chain sequence of SEQ ID NO: 1841 and the light chain sequence of SEQ ID NO: 1868 as shown in Group V in Table 7.
• In some embodiments, the activatable anti-PD-1 antibody includes a combination of the CDRs of the heavy chain sequence of SEQ ID NO: 1849 and a combination of the CDRs of the light chain sequence of SEQ ID NO: 1858 as shown in Group V in Table 7. In some embodiments, the activatable anti-PD-1 antibody includes a combination of the heavy chain sequence of SEQ ID NO: 1849 and the light chain sequence of SEQ ID NO: 1858 as shown in Group V in Table 7.
• In some embodiments, the activatable anti-PD-1 antibody includes a combination of the CDRs of the heavy chain sequence of SEQ ID NO: 1853 and a combination of the CDRs of the light chain sequence of SEQ ID NO: 1859 as shown in Group V in Table 7. In some embodiments, the activatable anti-PD-1 antibody includes a combination of the heavy chain sequence of SEQ ID NO: 1853 and the light chain sequence of SEQ ID NO: 1859 as shown in Group V in Table 7.
• In some embodiments, the activatable anti-PD-1 antibody includes a combination of the CDRs of the heavy chain sequence of SEQ ID NO: 1869 and a combination of the CDRs of the light chain sequence of SEQ ID NO: 737 as shown in Group V in Table 7. In some embodiments, the activatable anti-PD-1 antibody includes a combination of the heavy chain sequence of SEQ ID NO: 1869 and the light chain sequence of SEQ ID NO: 737 as shown in Group V in Table 7.
• In some embodiments, the activatable anti-PD-1 antibody includes a combination of the CDRs of the heavy chain sequence of SEQ ID NO: 1850 and a combination of the CDRs of the light chain sequence of SEQ ID NO: 1860 as shown in Group V in Table 7. In some embodiments, the activatable anti-PD-1 antibody includes a combination of the heavy chain sequence of SEQ ID NO: 1850 and the light chain sequence of SEQ ID NO: 1860 as shown in Group V in Table 7.
• n some embodiments, the activatable anti-PD-1 antibody includes a combination of the CDRs of the heavy chain sequence of SEQ ID NO: 1851 and a combination of the CDRs of the light chain sequence of SEQ ID NO: 1861 as shown in Group V in Table 7. In some embodiments, the activatable anti-PD-1 antibody includes a combination of the heavy chain sequence of SEQ ID NO: 1851 and the light chain sequence of SEQ ID NO: 1861 as shown in Group V in Table 7.
• In some embodiments, the activatable anti-PD-1 antibody includes a combination of the CDRs of the heavy chain sequence of SEQ ID NO: 1852 and a combination of the CDRs of the light chain sequence of SEQ ID NO: 737 as shown in Group V in Table 7. In some embodiments, the activatable anti-PD-1 antibody includes a combination of the heavy chain sequence of SEQ ID NO: 1852 and the light chain sequence of SEQ ID NO: 737 as shown in Group V in Table 7.
• In some embodiments, the activatable anti-PD-1 antibody includes a combination of the CDRs of the heavy chain sequence of SEQ ID NO: 1854 and a combination of the CDRs of the light chain sequence of SEQ ID NO: 737 as shown in Group V in Table 7. In some embodiments, the activatable anti-PD-1 antibody includes a combination of the heavy chain sequence of SEQ ID NO: 1854 and the light chain sequence of SEQ ID NO: 737 as shown in Group V in Table 7.
• In some embodiments, the activatable anti-PD-1 antibody includes a combination of the CDRs of the heavy chain sequence of SEQ ID NO: 1855 and a combination of the CDRs of the light chain sequence of SEQ ID NO: 737 as shown in Group V in Table 7. In some embodiments, the activatable anti-PD-1 antibody includes a combination of the heavy chain sequence of SEQ ID NO: 1855 and the light chain sequence of SEQ ID NO: 737 as shown in Group V in Table 7.
• In some embodiments, the activatable anti-PD-1 antibody includes a combination of the CDRs of a heavy chain sequence from the heavy chain sequences shown in Group W in Table 7. In some embodiments, the activatable anti-PD-1 antibody includes a combination of the CDRs of a light chain sequence from the light chain sequences shown in Group W in Table 7. In some embodiments, the activatable anti-PD-1 antibody includes a combination of the CDRs of a heavy chain sequence from the heavy chain sequences shown in Group W in Table 7 and the CDRs of a light chain sequence from the heavy chain sequences shown in Group W in Table 7.

• TABLE 7
  Variable Heavy Chain Region (VH) and Variable Light Chain Region
  (VL) Sequences for Activatable Antibodies that Bind PD-1
  Group A

  VH	QVQLVESGGDVVQPGGSLRLSCAASGVAFSNYGMHWVRQAPGKGLEWVAVIWYDGSNKYYADSVKGRFTISR
  	DNSKNMLYLQMNSLRAEDTAMYYCARNDDYWGQGTLVTVSS (SEQ ID NO: 615)
  VH	QVQLVESGGDVVQPGRSLRLSCAASGLTFTNYGFHWVRQAPGKGLEWVAVIWYDGSKKYYADSVKGRFTISR
  	DNSKNTLYLQMNNLRAEDTAVYYCATGDDYWGQGTLVTVSS (SEQ ID NO: 617)
  VH	QVYLVESGGGVVQPGRSLRLSCAASGFTFSNYGMHWVRQAPGKGLEWVALIWYDGSNKYYADSVKGRFTISR
  	DNSKNTLYLQMTSLRVEDTAVYYCASNVDHWGQGTLVTVSS (SEQ ID NO: 618)
  VH	QVQLVESGGGVVQPGRSLRLDCKASGITFSNSGMHWVRQAPGKGLEWVAVIWYDGSKRYYADSVKGRFTISR
  	DNSKNTLFLQMNSLRAEDTAVYYCATNDDYWGQGTLVTVSS (SEQ ID NO: 1346)
  VH	QLQLQESGPGLVKPSETLSLTCTVSGGSLSRSSFFWGWIRQPPGKGLEWIGSIYYSGSTYYNPSLKSRVTIS
  	VDTSKNQFSLKLSSVTAADTAVYYCVRDYDILTGDEDYWGQGTLVTVSS (SEQ ID NO: 620)
  VH	QVQLVESGGGVVQPGRSLRLSCTTSGITFSSYGFHWVRQAPGKGLEWVAVIWYDGSKKYYADSVKGRFTLSR
  	DDSKNTLYLQMNSLRAEDTAVYYCVTGDDYWGQGTLVTVSS (SEQ ID NO: 621)
  VH	QLQLQESGPGLVKPSETLSLTCSVSGGSLSRSSYFWGWIRQPPGKGLEWIASIFYSGETYFNPSLKSRVTIS
  	VDTSRNQFSLKLSSVTAADTAVYYCARDYDILTGDEDYWGQGTLVTVSS (SEQ ID NO: 623)
  VL	EIVLTQSPATLSLSPGERATLSCRASQSVSSYLAWYQQKPGQAPRLIIYDASNRATGIPARFSGSGSGTDFT
  	LTISSLEPEDFAVYYCQQRSNWPLTFGGGTKVEIK (SEQ ID NO: 624)
  VL	EIVLTQSPATLSLSPGERATLSCRASQSVSSYLAWYQQKPGQAPRLLIYDTSNRATGIPARFSGSGSGTDFT
  	LTISSLEPEDFAVYYCQQRSNWPLTFGGGTKVEIK (SEQ ID NO: 625)
  VL	EIVLTQSPATLSLSPGERATLSCRASQSVSSYLAWYQQKPGQAPRLLIYDASNRATGIPARFSGSGSGTDFT
  	LTISSLEPEDFAVYYCQQSSNWPRTFGQGTKVEIK (SEQ ID NO: 626)
  VL	DIQMTQSPSSLSASVGDRVSITCRASQGISSWLAWYQQKPEKAPKSLIYAASNLRSGVPSRFSGSGSGTDFT
  	LTISSLQPEDFATYYCQQYYSYPRTFGQGTKVEIK (SEQ ID NO: 628)
  VL	EIVLTQSPATLSLSPGERATLSCRASQSVSSYLAWYQQKPGQAPRLLIYDASNRATGIPARFSGSGSGTDFT
  	LTISSLEPEDFAVYYCQQRSNWPLTFGGGTKVEIK (SEQ ID NO: 629)
  VL	DIQMTQSPSSLSASVGDRVTITCRASQGISSWLAWYQQKPEKAPKSLIYAASSLQSGVPSRFSGSGSGTDFT
  	LTISSLQPEDFATYYCQQYYSYPRTFGQGTKVEIK (SEQ ID NO: 630)

  Group B

  VH	QVQLQQPGAELVKPGASVKLSCKASGYTFTSYYLYWMKQRPGQGLEWIGGVNPSNGGTNFSEKFKSKATLTV
  	DKSSSTAYMQLSSLTSEDSAVYYCTRRDSNYDGGFDYWGQGTTLTVSSAK (SEQ ID NO: 631)
  VH	QVQLQQPGAELVKPGTSVKLSCKASGYTFTNYYMYWVKQRPGQGLEWIGGINPSNGGTNFNEKFKNKATLTV
  	DSSSSTTYMQLSSLTSEDSAVYYCTRRDYRFDMGFDYWGQGTTLTVSSAK (SEQ ID NO: 632)
  VH	MDWTWSILFLVAAPTGAHSQVQLVQSGVEVKKPGASVKVSCKASGYTFTNYYMYWVRQAPGQGLEWMGGINP
  	SNGGTNFNEKFKNRVTLTTDSSTTTAYMELKSLQFDDTAVYYCARRDYRFDMGFDYWGQGTTVTVSS (SEQ
  	ID NO: 633)
  VH	QVQLVQSGVEVKKPGASVKVSCKASGYTFTNYYMYWVRQAPGQGLEWMGGINPSNGGTNFNEKFKNRVTLTT
  	DSSTTTAYMELKSLQFDDTAVYYCARRDYRFDMGFDYWGQGTTVTVSS (SEQ ID NO: 634)
  VH	EVQLVLSGGGFVQPGGSLKLSCAASGFTFSSYAMSWVRQNPERRLVWVATITGGGRNTYYPDSVKGRFTISR
  	DNAKNTLYLQMSSLRSEDTAMYYCTRQGYDGYTWFAYWGQGTLVTVS (627)
  VL	DIVLTQSPTSLAVSLGQRATISCRASKSVSTSGFSYLHWYQQKPGQPPKLLIFLASNLESGVPARFSGSGSG
  	TDFTLNIHPVEEEDAATYYCQHSWELPLTFGAGTKLELK (SEQ ID NO: 635)
  VL	DIVLTQSPASLAVSLGQRAAISCRASKGVSTSGYSYLHWYQQKPGQSPKLLIYLASYLESGVPARFSGSGSG
  	TDFTLNIHPVEEEDAATYYCQHSRDLPLTFGTGTKLELK (SEQ ID NO: 636)
  VL	MAPVQLLGLLVLFLPAMRCEIVLTQSPATLSLSPGERATLSCRASKGVSTSGYSYLHWYQQKPGQAPRLLIY
  	LASYLESGVPARFSGSGSGTDFTLTISSLEPEDFAVYYCQHSRDLPLTFGGGTKVEIK (SEQ ID
  	NO: 637)
  VL	EIVLTQSPATLSLSPGERATLSCRASKGVSTSGYSYLHWYQQKPGQAPRLLIYLASYLESGVPARFSGSGSG
  	TDFTLTISSLEPEDFAVYYCQHSRDLPLTFGGGTKVEIK (SEQ ID NO: 638)
  VL	MAPVQLLGLLVLFLPAMRCEIVLTQSPLSLPVTPGEPASISCRASKGVSTSGYSYLHWYLQKPGQSPQLLIY
  	LASYLESGVPDRFSGSGSGTDFTLKISRVEAEDVGVYYCQHSRDLPLTFGQGTKLEIK (SEQ ID
  	NO: 639)
  VL	EIVLTQSPLSLPVTPGEPASISCRASKGVSTSGYSYLHWYLQKPGQSPQLLIYLASYLESGVPDRFSGSGSG
  	TDFTLKISRVEAEDVGVYYCQHSRDLPLTFGQGTKLEIK (SEQ ID NO: 640)
  VL	MAPVQLLGLLVLFLPAMRCDIVMTQTPLSLPVTPGEPASISCRASKGVSTSGYSYLHWYLQKPGQSPQLLIY
  	LASYLESGVPDRFSGSGSGTAFTLKISRVEAEDVGLYYCQHSRDLPLTFGQGTKLEIK (SEQ ID
  	NO: 641)
  VL	DIVMTQTPLSLPVTPGEPASISCRASKGVSTSGYSYLHWYLQKPGQSPQLLIYLASYLESGVPDRFSGSGSG
  	TAFTLKISRVEAEDVGLYYCQHSRDLPLTFGQGTKLEIK (SEQ ID NO: 642)
  VL	DIVLTQSPTSLAVSLGQRATISCRASESVDNSGISFMNWFQQKPGQPPKLLIYAASNPGSGVPARFSGSGSG
  	TDFSLNIHPMEEDDTAMYFCQQSKEVPWTFGGGTELEIKR (SEQ ID NO: 725)
  HC	MAVLGLLFCLVTFPSCVLSQVQLVQSGVEVKKPGASVKVSCKASGYTFTNYYMYWVRQAPGQGLEWMGGINP
  	SNGGTNFNEKFKNRVTLTTDSSTTTAYMELKSLQFDDTAVYYCARRDYRFDMGFDYWGQGTTVTVSSASTKG
  	PSVFPLAPCSRSTSESTAALGCLVKDYFPEPVTVSWNSGALTSGVHTFPAVLQSSGLYSLSSVVTVPSSSLG
  	TKTYTCNVDHKPSNTKVDKRVESKYGPPCPPCPAPEFLGGPSVFLFPPKPKDTLMISRTPEVTCVVVDVSQE
  	DPEVQFNWYVDGVEVHNAKTKPREEQFNSTYRVVSVLTVLHQDWLNGKEYKCKVSNKGLPSSIEKTISKAKG
  	QPREPQVYTLPPSQEEMTKNQVSLTCLVKGFYPSDIAVEWESNGQPENNYKTTPPVLDSDGSFFLYSRLTVD
  	KSRWQEGNVFSCSVMHEALHNHYTQKSLSLSLGK (SEQ ID NO: 643)
  HC	QVQLVQSGVEVKKPGASVKVSCKASGYTFTNYYMYWVRQAPGQGLEWMGGINPSNGGTNFNEKFKNRVTLTT
  	DSSTTTAYMELKSLQFDDTAVYYCARRDYRFDMGFDYWGQGTTVTVSSASTKGPSVFPLAPCSRSTSESTAA
  	LGCLVKDYFPEPVTVSWNSGALTSGVHTFPAVLQSSGLYSLSSVVTVPSSSLGTKTYTCNVDHKPSNTKVDK
  	RVESKYGPPCPPCPAPEFLGGPSVFLFPPKPKDTLMISRTPEVTCVVVDVSQEDPEVQFNWYVDGVEVHNAK
  	TKPREEQFNSTYRVVSVLTVLHQDWLNGKEYKCKVSNKGLPSSIEKTISKAKGQPREPQVYTLPPSQEEMTK
  	NQVSLTCLVKGFYPSDIAVEWESNGQPENNYKTTPPVLDSDGSFFLYSRLTVDKSRWQEGNVFSCSVMHEAL
  	HNHYTQKSLSLSLGK (SEQ ID NO: 644)
  HC	MAVLGLLFCLVTFPSCVLSQVQLVQSGVEVKKPGASVKVSCKASGYTFTNYYMYWVRQAPGQGLEWMGGINP
  	SNGGTNFNEKFKNRVTLTTDSSTTTAYMELKSLQFDDTAVYYCARRDYRFDMGFDYWGQGTTVTVSSASTKG
  	PSVFPLAPSSKSTSGGTAALGCLVKDYFPEPVTVSWNSGALTSGVHTFPAVLQSSGLYSLSSVVTVPSSSLG
  	TQTYICNVNHKPSNTKVDKKVEPKSCDKTHTCPPCPAPELLGGPSVFLFPPKPKDTLMISRTPEVTCVVVDV
  	SHEDPEVKFNWYVDGVEVHNAKTKPREEQYNSTYRVVSVLTVLHQDWLNGKEYKCKVSNKALPAPIEKTISK
  	AKGQPREPQVYTLPPSRDELTKNQVSLTCLVKGFYPSDIAVEWESNGQPENNYKTTPPVLDSDGSFFLYSKL
  	TVDKSRWQQGNVFSCSVMHEALHNHYTQKSLSLSPGK (SEQ ID NO: 645)
  HC	QVQLVQSGVEVKKPGASVKVSCKASGYTFTNYYMYWVRQAPGQGLEWMGGINPSNGGTNFNEKFKNRVTLTT
  	DSSTTTAYMELKSLQFDDTAVYYCARRDYRFDMGFDYWGQGTTVTVSSASTKGPSVFPLAPSSKSTSGGTAA
  	LGCLVKDYFPEPVTVSWNSGALTSGVHTFPAVLQSSGLYSLSSVVTVPSSSLGTQTYICNVNHKPSNTKVDK
  	KVEPKSCDKTHTCPPCPAPELLGGPSVFLFPPKPKDTLMISRTPEVTCVVVDVSHEDPEVKFNWYVDGVEVH
  	NAKTKPREEQYNSTYRVVSVLTVLHQDWLNGKEYKCKVSNKALPAPIEKTISKAKGQPREPQVYTLPPSRDE
  	LTKNQVSLTCLVKGFYPSDIAVEWESNGQPENNYKTTPPVLDSDGSFFLYSKLTVDKSRWQQGNVFSCSVMH
  	EALHNHYTQKSLSLSPGK (SEQ ID NO: 646)
  LC	MAPVQLLGLLVLFLPAMRCEIVLTQSPATLSLSPGERATLSCRASKGVSTSGYSYLHWYQQKPGQAPRLLIY
  	LASYLESGVPARFSGSGSGTDFTLTISSLEPEDFAVYYCQHSRDLPLTFGGGTKVEIKRTVAAPSVFIFPPS
  	DEQLKSGTASVVCLLNNFYPREAKVQWKVDNALQSGNSQESVTEQDSKDSTYSLSSTLTLSKADYEKHKVYA
  	CEVTHQGLSSPVTKSFNRGEC (SEQ ID NO: 647)
  LC	EIVLTQSPATLSLSPGERATLSCRASKGVSTSGYSYLHWYQQKPGQAPRLLIYLASYLESGVPARFSGSGSG
  	TDFTLTISSLEPEDFAVYYCQHSRDLPLTFGGGTKVEIKRTVAAPSVFIFPPSDEQLKSGTASVVCLLNNFY
  	PREAKVQWKVDNALQSGNSQESVTEQDSKDSTYSLSSTLTLSKADYEKHKVYACEVTHQGLSSPVTKSFNRG
  	EC (SEQ ID NO: 648)
  LC	MAPVQLLGLLVLFLPAMRCEIVLTQSPLSLPVTPGEPASISCRASKGVSTSGYSYLHWYLQKPGQSPQLLIY
  	LASYLESGVPDRFSGSGSGTDFTLKISRVEAEDVGVYYCQHSRDLPLTFGQGTKLEIKRTVAAPSVFIFPPS
  	DEQLKSGTASVVCLLNNFYPREAKVQWKVDNALQSGNSQESVTEQDSKDSTYSLSSTLTLSKADYEKHKVYA
  	CEVTHQGLSSPVTKSFNRGEC (SEQ ID NO: 649)
  LC	EIVLTQSPLSLPVTPGEPASISCRASKGVSTSGYSYLHWYLQKPGQSPQLLIYLASYLESGVPDRFSGSGSG
  	TDFTLKISRVEAEDVGVYYCQHSRDLPLTFGQGTKLEIKRTVAAPSVFIFPPSDEQLKSGTASVVCLLNNFY
  	PREAKVQWKVDNALQSGNSQESVTEQDSKDSTYSLSSTLTLSKADYEKHKVYACEVTHQGLSSPVTKSFNRG
  	EC (SEQ ID NO: 650)
  LC	MAPVQLLGLLVLFLPAMRCDIVMTQTPLSLPVTPGEPASISCRASKGVSTSGYSYLHWYLQKPGQSPQLLIY
  	LASYLESGVPDRFSGSGSGTAFTLKISRVEAEDVGLYYCQHSRDLPLTFGQGTKLEIKRTVAAPSVFIFPPS
  	DEQLKSGTASVVCLLNNFYPREAKVQWKVDNALQSGNSQESVTEQDSKDSTYSLSSTLTLSKADYEKHKVYA
  	CEVTHQGLSSPVTKSFNRGEC (SEQ ID NO: 651)
  LC	DIVMTQTPLSLPVTPGEPASISCRASKGVSTSGYSYLHWYLQKPGQSPQLLIYLASYLESGVPDRFSGSGSG
  	TAFTLKISRVEAEDVGLYYCQHSRDLPLTFGQGTKLEIKRTVAAPSVFIFPPSDEQLKSGTASVVCLLNNFY
  	PREAKVQWKVDNALQSGNSQESVTEQDSKDSTYSLSSTLTLSKADYEKHKVYACEVTHQGLSSPVTKSFNRG
  	EC (SEQ ID NO: 652)

  Group C

  VH	DVQLQESGPGLVKPSQSLSLTCTVTGYSITSDYAWNWIRQFPGNKLEWMGYINYSGSTSYNPSLKSRISITR
  	DTSKNQFFLQLNSVTTEDTATYYCARWIGSSAWYFDVWGAGTTVTV (SEQ ID NO: 726)
  VL	DVLMTQTPLSLPVSLGDQASISCRSGQNIVHSNGNTYLEWYLQKPGQSPKLLIYKVSNRFFGVPDRISGSGS
  	GTDFTLKISRVEAEDLGVYFCFQGSHVPFTFGSGTKLEIK (SEQ ID NO: 727)
  VH	QVQLQQPGAELVKPGASVKLSCKASGYTFTTYYLYWVRQRPGQGLEWIGGINPSNGGTNFNEKFKSKATLTV
  	DKSSSTAYMQLNSLTSEDSAVYYCTRRDYRYDRGFDYWGQGTSVTV (SEQ ID NO: 728)
  VL	DIVLTQSPASLAVSLGQRATISCRASKSVSTSGFNYIHWYQQKPGQPPKLLIYLASNLESGVPARFSGSGSG
  	TDFTLNIHPVEDEDAATYYCQHSRELPLTFGAGTKLEIK (SEQ ID NO: 729)
  VH	QVQLQQSGAELVKPGASVKMSCKAFGYTFTTYPIEWMKQNHGKSLEWIGNFHPYNDDTKYNEKFKGKAKLTV
  	EKSSTTVYLELSRLTSDDSAVYYCARENYGSHGGFVYWGQGTLVTV (SEQ ID NO: 730)
  VL	ENVLTQSPAIMSASPGEKVTMTCRASSSVISSYLHWYQQKSGASPKLWIYSTSNLASGVPDRFSGSGSGTSY
  	SLTISSVEAEDAATYYCQQYNGYPLTFGAGTKLEIK (SEQ ID NO: 731)

  Group D

  	LFTVTVPKELYIIEHGSNVTLECNFDTGSHVNLGAITASLQKVENDTSPHRERATLLEEQLPLGKASFHIPQ
  	VQVRDEGQYQCIIIYGVAWDYKYLTLKVKASYRKINTHILKVPETDEVELTCQATGYPLAEVSWPNVSVPAN
  	TSHSRTPEGLYQVTSVLRLKPPPGRNFSCVFWNTHVRELTLASIDLQSQMEPRTHPTWEPKSCDKTHTCPPC
  	PAPELLGGPSVFLFPPKPKDTLMISRTPEVTCVVVDVSHEDPEVKFNWYVDGVEVHNAKTKPREEQYNSTYR
  	VVSVLTVLHQDWLNGKEYKCKVSNKALPAPIEKTISKAKGQPREPQVYTLPPSRDELTKNQVSLTCLVKGFY
  	PSDIAVEWESNGQPENNYKTTPPVLDSDGSFFLYSKLTVDKSRWQQGNVFSCSVMHEALHNHYTQKSLSLSP
  	GK (SEQ ID NO: 732)

  Group E

  VH	EVQLVQSGAEVKKPGASVKVSCKASGYRFTSYGISWVRQAPGQGLEWMGWISAYNGNTNYAQKLQGRVTMTT
  	DTSTNTAYMELRSLRSDDTAVYYCARDADYSSGSGYWGQGTLVTVSS (SEQ ID NO: 733)
  VH	QVQLVQSGAEVKKPGASVRVSCKASGYTLTSYYIHWVRQAPGQGLEWMGIINPRGATISYAQKFQGRVTMTR
  	DTSTSTVYMELRNLKSEDTALYYCATAGIYGFDFDYWGRGTLVTVSS (SEQ ID NO: 734)
  VH	QVQLQESGPGLVKPSQTLSLTCTVSGGSISSGAYYWSWIRQHPGKGLEWIGYIYYNGNTYYNPSLRSLVTIS
  	VDASKNQFSLKLSSVTAADTAVYYCARASDYVWGGYRYMDAFDIWGRGTLITVSS (SEQ ID NO: 735)
  VH	GAHSEVQLVQSGGGVVQPGRSLRLSCAASGFTFSSYWCDRMSWVRQAPGKGLEWVSAISGSGGSTYYADSVK
  	GRFTISRDNSKNTLYLQMNSLRAEDTAVYYCAKENWGSYFDLWGQGTTVTVSS (SEQ ID NO: 736)
  VL	SYELTQPPSVSVSPGQTARITCSGDALPKQYAYWYQQKPGQAPVMVIYKDTERPSGIPERFSGSSSGTKVTL
  	TISGVQAEDEADYYCQSADNSITYRVFGGGTKVTVL (SEQ ID NO: 737)
  VL	QSALTQPASVSGSPGQSITISCTGTSNDVGGYNYVSWYQHHPGKAPKLIIYDVTNRPSGVSDRFSGSKSGNT
  	ASLTISGLLAEDEGDYYCSSYTIVTNFEVLFGGGTKLTV (SEQ ID NO: 738)
  VL	QSVLTQPPSASGTPGQRVTISCSGSNSNIGSNSVNWYQQLPGTAPKLLIYGNNQRPSGVPDRFSGSKSGTSA
  	SLAISGLQSENEADYYCAAWDDSLNGPVFGRGTKVTVLGE (SEQ ID NO: 739)
  VL	GVHSDIVMTQSPSTLSASVGDRVTITCRASQGISSWLAWYQQKPGRAPKVLIYKASTLESGVPSRFSGSGSG
  	TDFTLTISSLQPEDFATYYCQQSYSTPWTFGQGTKLEIKR (SEQ ID NO: 740)

  Group F

  VH	QVQLVQSGHEVKQPGASVKMSCKASGYSFTSSWIHWVKQAPGQGLEWIGYIYPSTGFTEYNQKFKDRATLTA
  	DKSTSTAYMELSSLRSEDTAVYYCARWRDSSGYHAMDYWGQGTLVTVSS (SEQ ID NO: 741)
  VH	QVQLVQSGHEVKQPGASVKMSCKASGYSFTSSWIHWVRQAPGQGLEWIGYIYPSTGFTEYNQKFKDRATLTA
  	DKSTSTAYMELSSLRSEDTAVYYCARWRDSSGYHAMDYWGQGTLVTVSS (SEQ ID NO: 742)
  VL	EIVLTQSPATLSLSPGQRLTISCRASQSVSTSGYSYMHWYQQKPDQSPKLLIKFGSNLESGIPARFSGSGSG
  	TDFTLTISSLEPEDFATYYCQHSWEIPYTFGQGTKLEIK (SEQ ID NO: 743)
  VL	DIVLTQSPATLSLSPGQRLTISCRASQSVSTSGYSYMHWYQQKPDQSPKLLIKFGSNLESGIPARFSGSGSG
  	TDFTLTISSLEPEDFAVYYCQHSWEIPYTFGQGTKLEIK (SEQ ID NO: 744)

  Group H

  VH	QGQLVQSGAEVKKPGASVKVSCKASGYTFTDYEMHWVRQAPIHGLEWIGVIESETGGTAYNQKFKGRVTITA
  	DKSTSTAYMELSSLRSEDTAVYYCAREGITTVATTYYWYFDVWGQGTTVTVSS (SEQ ID NO: 745)
  VL	DVVMTQSPLSLPVTLGQPASISCRSSQSIVHSNGNTYLEWYLQKPGQSPQLLIYKVSNRFSGVPDRFSGSGS
  	GTDFTLKISRVEAEDVGVYYCFQGSHVPLTFGQGTKLEIK (SEQ ID NO: 746)

  Group I

  VH	MGLGLQWVFFVALLKGVHCEVRLLESGGGLVKPEGSLKLSCVASGFTFSDYFMSWVRQAPGKGLEWVAHIYT
  	KSYNYATYYSGSVKGRFTISRDDSRSMVYLQMNNLRTEDTATYYCTRDGSGYPSLDFWGQGTQVTVSSATTT
  	APSVYPLAPACDSTTKS (SEQ ID NO: 747)
  VL	YELTQPPSASVNVGETVKITCSGDQLPKYFADWFHQRSDQTILQVIYDDNKRPSGIPERISGSSSGTTATLT
  	IRDVRAEDEGDYYCFSGYVDSDSKLYVFGSGTQLTVLGGPKSSPKVTVFPPSPEELRTNKATLVCLVNDFYP
  	GSATVTWKANGATINDGVKTTKPSKQGQNYMTSSYLSLTADQWKSHNRVSCQVTHEGETVEKSLSPAECL
  	(SEQ ID NO: 748)
  Bs	METDTLLLWVLLLWVPGSTGDAAQPARRARRTKLGTELGSPGLQEFEVRLLESGGGLVKPEGSLKLSCVASG
  Ab	FTFSDYFMSWVRQAPGKGLEWVAHIYTKSYNYATYYSGSVKGRFTISRDDSRSMVYLQMNNLRTEDTATYYC
  	TRDGSGYPSLDFWGQGTQVTVSSGGGGSDIQMTQSPSSLPASLGDRVTINCQASQDISNYLNWYQQKPGKAP
  	KLLIYYTNKLADGVPSRFSGSGSGRDSSFTISSLESEDIGSYYCQQYYNYPWTFGPGTKLEIKGGGGSGGGG
  	SGGGGSEVQLVESGGGLVQPGKSLKLSCEASGFTFSGYGMHWVRQAPGRGLESVAYITSSSINIKYADAVKG
  	RFTVSRDNAKNLLFLQMNILKSEDTAMYYCARFDWDKNYWGQGTMVTVSSGGGGSYELTQPPSASVNVGETV
  	KITCSGDQLPKYFADWFHQRSDQTILQVIYDDNKRPSGIPERISGSSSGTTATLTIRDVRAEDEGDYYCFSG
  	YVDSDSKLYVFGSGTQLTVLGPRGGPEQKLISEEDLNSAVDHHHHHH (SEQ ID NO: 749)

  Group J

  VH	QLVQSGAEVKKPGASVKVSCKASGYTFTSYGISWVRQAPGQGLEWMGWISAYNGNTNYAQKLQGRVTMTTDT
  	STSTATMELRSLRSDDTAVYYCARGRGYSYGIDAFDIWGQGTMVT (SEQ ID NO: 750)
  VH	LSYVLTQPPSVSVSPGQTARITCSGDALPKQYAYWYQQKPGQAPVLVIYKDSERPSGIPERFSGSSSGTTVT
  	LTISGVQAEDEADYYCQSADSSGTYVVFGGGTKLTVLGQP (SEQ ID NO: 751)

  Group K

  VH	QVQLQQSGPGLVRPSQTLSLSCDISGDSVSSNSATWNWIRQSPSRGLEWLGRTFYRSKWYHDYALSVKSRIT
  	INPDTSKNQFSLQLNSVSPGDTAVYFCVREDIDGRLDYWGQGTLVTVSS (SEQ ID NO: 752)
  VH	QVQLVQSGSELKKPGASVKISCKASGYIFSDNGVNWVRQAPGQGLEWMGWINTKIGNPTYAQGFTGRFVFSL
  	DTSVSTTYLQISSLQAGDTAVYYCAREHDYYYGMDVWGQGTTVTVSS (SEQ ID NO: 753)
  VH	MAEVQLLESGAEVKKPGASVKVSCKASGYTFTSHYMHWVRQAPGQGLEWMGVINPSGGSTSYAQKFQGRVTM
  	TRDTSTSTVYMDLSSLRSEDTAVYYCARRSEAYYHGMDVWGQGTTVTVSS (SEQ ID NO: 754)
  VH	EVQLVQSGSELKKPGASVKISCKASGYIFSDNGVNWVRQAPGQGLEWMGWINTKIGNPTYAQGFTGRFVFSL
  	DTSISTTYLQISSLQAGDTAVYYCAREHDYYYGMDVWGQGTTVTVSS (SEQ ID NO: 755)
  VH	QVQLVESGGGLVQPGGSLRLSCEATGFTFSRYWMHWVRQAPGKGLEWVSSISSSSSYIYYADSVKGRFTISR
  	DNAKNSLYLQMNSLRAEDTAVYYCARDTLEYYGSGILENAMGYYGMDVWGQGTTVTVSS (SEQ ID
  	NO: 756)
  VH	EVQLVESGGGLVRPGGSLRLACAASGFSFSDYYMTWIRQAPGRGLEWIAYISDSGQTVHYADSVKGRFTISR
  	DNTKNSLFLQVNTLRAEDTAVYYCAREDLLGYYLQSWGQGTLVTVSS (SEQ ID NO: 757)
  VH	EVQLVESGGGVVQPGRSLRLSCAASGFTFSSYWMSWVRQAPGKGLEWVANIKQDGSEKYYVDSVKGRFTISR
  	DNAKNSLYLQMNSLRAEDTAVYYCAREGEHDAFDIWGQGTMVTVSS (SEQ ID NO: 758)
  VH	QVQLVQSGSELKKPGASVKISCKASGYIFSDNGVNWVRQAPGQGLEWMGWINTKIGNPTYAQGFTGRFVFSL
  	DTSVSTTYLQISSLQAGDTAVYYCAREHDYYYGMDVWGQGTTVTVSS (SEQ ID NO: 759)
  VH	QVQLVQSGSELKKPGASVKISCKASGYIFSDNGVNWVRQAPGQGLEWMGWINTKIGNPTYAQGFTGRFVFSL
  	DTSVSTTYLQISSLQAGDTAVYYCAREHDYYYGMDVWGQGTTVTVSS (SEQ ID NO: 760)
  VH	QVQLVQSGAEVKKPGASVKVSCKASGYTFTRYTMHWVRQAPGQRLEWMGWINAGNGNTKYSQKFQGRVTITR
  	DTSASTAYMELSSLRSEDTAVYYCAKVSAGTESWFDPWGQGTLVTVSS (SEQ ID NO: 761)
  VH	QVQLVQSGAEVKKPGASVKVSCKASGYTFTSYGISWVRQAPGQGLEWMGWISAYNGNTNYAQKLQGRVTMTT
  	DTSTSTAYMELRSLRSDDTAVYYCARGLYGDEDYWGQGTLVTVSS (SEQ ID NO: 762)
  VH	QVQLVQSGSELKKPGASVKISCKASGYIFSDNGVNWVRQAPGQGLEWMGWINTKIGNPTYAQGFTGRFVFSL
  	DTSISTTYLQISSLQAGDTAVYYCAREHDYYYGMDVWGQGTTVTVSS (SEQ ID NO: 763)
  VH	QMQLVQSGAEVKKPGESLKISCKGSGYSFTSYWIGWVRQMPGKGLEWMGIIYPGDSDTRYSPSFQGQVTISA
  	DKSISTAYLQWSSLKASDTAMYYCASGVTRKRYSSSWPPFDYWGQGTLVTVSS (SEQ ID NO: 764)
  VH	QVQLQQWGAGLLKSSETLSLSCAVYGGTFRDDHWSWIRQPPGKGLEWIGESHHTGRTIYNPSLRSRVTMSID
  	TSKNEFSLILRSVTAADTATYFCARGNNYVWGNQEDFWGQGTLVTVSS (SEQ ID NO: 765)
  VH	QVQLQQSGPGLVRPSQTLSLSCDISGDSVSSNSATWNWIRQSPSRGLEWLGRTFYRSKWYHDYALSVKSRIT
  	INPDTSKNQFSLQLNSVSPGDTAVYFCVREDIDGRLDYWGQGTLVTVSS (SEQ ID NO: 766)
  VH	EVQLVESGGALVQPGGSLRLSCAVSGFTFSDHYMDWVRQAPGKGLEWVARSRNKGNSYTTEYAASVRGRFTI
  	SRDDSKNSLYLQMNSLKTEDTAVYYCVRVGVVPALDGMDVWGQGTTVTVSS (SEQ ID NO: 767)
  VH	EVQLVESGGGLVQPGGSLRLSCAASGFTFSSYWMHWVRQAPGKGLEWVSSISSSSSYIYYADSVKGRFTISR
  	DNAKNSLYLQMNSLRAEDTAVYYCARDTLEYYGSGILENAMGYYGMDVWGQGTTVTVSS (SEQ ID
  	NO: 768)
  VH	EVQLLESGGGVVQTGRSLRLSCSDSGSTERSQAMHWVRQTPGKGLEWLAVTSHDGSKTYYADSVKGRFTISR
  	DNSKNTLYLQMNSLRGEDTAVYYCARGGRGYTYDHSFFDYWGQGTLVTVSS (SEQ ID NO: 769)
  VH	QVQLVQSGSELKKPGASVKISCKASGYIFSDNGVNWVRQAPGQGLEWMGWINTKDGNPTYAQGFTGRFVFSL
  	DTSISTTYLQISSLQAGDTAVYYCAREHDYYYGMDVWGQGTTVTVSS (SEQ ID NO: 770)
  VH	QVQLVQSGSELKKPGASVKISCKASGYIFSDNGVNWVRQAPGQGLEWMGWINTKTGNPTYAQGFTGRFVFSL
  	DTSISTTYLQISSLQAGDTAVYYCAREHDYYYGMDVWGQGTTVTVSS (SEQ ID NO: 771)
  VH	QVQLVQSGSELKKPGASVKISCKASGYTFSDNGVNWVRQAPGQGLEWMGWINTKDGNPTYAQGFTGRFVFSL
  	DTSISTTYLQISSLQAGDTAVYYCAREHDYYYGMDVWGQGTTVTVSS (SEQ ID NO: 772)
  VH	QVQLVQSGSELKKPGASVKISCKASGYTFSDNGVNWVRQAPGQGLEWMGWINTKTGNPTYAQGFTGRFVFSL
  	DTSISTTYLQISSLQAGDTAVYYCAREHDYYYGMDVWGQGTTVTVS (SEQ ID NO: 773)
  VH	QVQLVQSGSELKKPGASVKISCKASGYKFSDNGVNWVRQAPGQGLEWMGWINTKSGNPTYAQGFTGRFVFSL
  	DTSISTTYLQISSLQAGDTAVYYCAREHDYYYGMDVWGQGTTVTVSS (SEQ ID NO: 774)
  VH	QVQLVQSGSELKKPGASVKISCKASGYTFSDNGVNWVRQAPGQGLEWMGWINTKSGNPTYAQGFTGRFVFSL
  	DTSISTTYLQISSLQAGDTAVYYCAREHDYYYGMDVWGQGTTVTVSS (SEQ ID NO: 775)
  VH	QVQLVQSGSELKKPGASVKISCKASGYKFSDNGVNWVRQAPGQGLEWMGWINTKDGNPTYAQGFTGRFVFSL
  	DTSISTTYLQISSLQAGDTAVYYCAREHDYYYGMDVWGQGTTVTVSS (SEQ ID NO: 776)
  VL	LPVLTQPASVSGSPGQSITISCTGTSSDVGGYNYVSWYQQHPGKAPKLMIYEVSKRPSGVPDRFSGSKSGNT
  	ASLTVSGLQAEDEADYYCSAWDDSLNADVFGGGTKLTVL (SEQ ID NO: 777)
  VL	QPVLTQPPSASGTPGQRVTISCSGSSSNIGTNTVNWYQQVPGTAPKLLIHGNDQRPSGVPDRFSGSKSDTSA
  	SLAITGLQSDDDADYYCSAWDDSLNADVFGGGTKLTVL (SEQ ID NO: 778)
  VL	QAVLTQPPSASATPGQRVTISCSGSDSNIGTNYVYWYQQFPGTAPQPLIYRDNQRPSGVPDRFSGSKSGTSA
  	SLAISGLRSEDEATYFCSTWDDSLNGWVFGGGTKLTVL (SEQ ID NO: 779)
  VL	QPVLTQPRSVSGSPGQSITTSCTGTSSDVGGYNYVSWYQQHPGKAPKLMIYEVSNRPSGVSNRFSGSKSGNT
  	ASLTISGLQAEDEADYYCSSYTSSSTLEVFGTGTKVTVL (SEQ ID NO: 780)
  VL	YELMQPPSVSGAPGQRVTISCTGSSSNIGAAYDVHWYQQLPGKAPKLVMFANSNRPSGVPDRFSGSKSGTSA
  	SLAITGLQAEDEADYYCQSYDISLRAYVFGTGTKLTVL (SEQ ID NO: 781)
  VL	SYELMQPPSASGTPGQRVTISCSGSSSNIGTNTVNWYQHLPGTAPKLLIYSNNQRPSGVPDRFSGSKSGTSA
  	SLAISGLQSEDEADYYCATWDDSPNGWVFGGGTKLTVL (SEQ ID NO: 782)
  VL	QAVLTQPPSVSAAPGQRVTISCSGSNSNIADTYVSWYQQLPGTAPRLLIYDNDQRPSGIPDRFSGSKSGTSA
  	TLGITGLQTGDEADYYCGTWDSSLSGVFGTGTKVTVL (SEQ ID NO: 783)
  VL	QSVLTQPASVSGSPGQSVTISCTGSSSDVGAYNFVSWYRQYPGKAPKLLIYEVNKRPSDVPDRFSGSKFGNT
  	ASLTVSGLQADDEADYYCSSYAGSTDVFGTGTKVTVL (SEQ ID NO: 784)
  VL	LPVLTQPPSVSGTPGQRVTISCSGSSSNIGSNTVNWYQQLPGTAPKLLIYTNNQRPSGVPDRFSGSKSGTSA
  	SLAISGLQSEDEADYYCAAWDESLNGDVFGTGTKVTVL (SEQ ID NO: 785)
  VL	AIRMTQSPSFLSASVGDRVTITCRTSQNIYNYLNWYQQKPGKAPELLIFVASSLQSGVPSRFSGSGSGTDFT
  	LTISSLQPEDFATYFCLQDHSYPYTFGQGTKVEIK (SEQ ID NO: 786)
  VL	LPVLTQPPSVSEVPGQRVTISCSGGISNIGSNAVNWYQHFPGKAPKLLIYYNDLLPSGVSDRFSASKSGTSA
  	SLAISGLRSEDEADYYCAAWDDNLSAYVFATGTKVTVL (SEQ ID NO: 787)
  VL	QSALTQPPSASGSPGQSVTISCTGTSSDVGGYNYVSWYQHHPGKAPKLMIYEVSKRPSGVPDRFSGSKSAIT
  	ASLTISGLLTEDEADYYCSAWDDSLNADVFGGGTKVTVL (SEQ ID NO: 788)
  VL	DIQMTQSPSSLSASVGDRVTITCRASQSISTYLNWYQQKPGKAPKVLITDASSLETGVPSRFSGSGSGTDFT
  	FTISSLQPEDTATYFCQQYDDLPPTFGQGTKLEIK (SEQ ID NO: 789)
  VL	QAGLTQPRSVSGSPGQSVTISCTGTSSDVGGYNYVSWYQQHPGKAPKLMIYDVTKRPSGVSNRFSGSKSGNT
  	ASLTISGLQAEDEADYYCSSYTSSSTYVFGTGTKVTVL (SEQ ID NO: 790)
  VL	QPVLTQPASVSGSPGQSITISCTGTSSDVGGYNYVSWYQQHPGKAPKLMIYDVSNRPSGVSNRFSGSKSGNT
  	ASLAITGLQSDDDADYYCSAWDDSLNADVFGGGTKLTVL (SEQ ID NO: 791)
  VL	QAGLTQPPSVSKGLRQTATLTCTGNSNNIGDQGAAWLQQHQGHPPRLLSYRNNNRPSGISERLSASRSGNIA
  	SLTITGLQPEDEADYYCSAWDSSLSVWVFGGGTKLTVL (SEQ ID NO: 792)
  VL	QAVLTQPPSASGTPGQRVTISCSGSSSNIGSNTVNWYQQLPGTAPKLLIYSNNQRPSGVPDRFSGSKSGTSA
  	SLAISGLQSEDEADYYCAAWDDSLNGYVFGTGTKLTVL (SEQ ID NO: 793)
  VL	AIRMTQSPSTLSASVGDRVTITCRASENIRNLLAWYQQKPGKAPELLIHGASTLGTGVPSRFSGGGSGTEFT
  	LTISSLQPDDFATYYCQQYESYFNTFGQGTKVEIK (SEQ ID NO: 794)

  Group L

  VH	QVQLVESGPGVKKPGSSLKLSCTVSGFTFSSYDYYMHWVRQAPGNGLEWMAVIWYSGSNTYYNDSLKSRFSI
  	TRDNSKNTAYMQLNSLRAEDTAVYYCARAYFGVDVWGQGTLVTVSS (SEQ ID NO: 795)
  VL	DIVMTQSPASLSVSVGDRATISCRASQGIGNTLAWYQQKPGQAPKRLLIYRASQGIGNTLAGVPARFSGDGD
  	GTDFTLTIDDLEEPEDFATYYCQQYDHVPLTFGQGTKLEIK (SEQ ID NO: 796)

  Group M

  VH	EVQLVQSGAEVKKPGASVKVSCKAFGYTFTTYPIEWMRQAHGQGLEWIGNFHPYNDDTKYNEKFKGRVTMTV
  	DKSTTTVYMELSSLRSEDTAVYYCARENYGSHGGFVYWGQGTLVTVS (SEQ ID NO: 797)
  VH	EVQLVQSGAEVKKPGASVKVSCKAFGYTFTTYPIEWMRQAHGQGLEWIGNFHPYNDDTKYNEKFKGRVTMTR
  	DTSTSTVYMELSSLRSEDTAVYYCARENYGSHGGFVYWGQGTLVTVS (SEQ ID NO: 798)
  VH	EVQLVQSGAEVKKPGASVKVSCKAFGYTFTTYPIEWVRQAPGQGLEWMGNFHPYNDDTKYNEKFKGRVTMTR
  	DTSTSTVYMELSSLRSEDTAVYYCARENYGSHGGFVYWGQGTLVTVS (SEQ ID NO: 799)
  VH	EVQLVQSGAEVKKPGSSVKVSCKASGYTFTTYPIEWVRQAPGQGLEWMGNFHPYNDDTKYNEKFKGRVTITA
  	DKSTSTAYMELSSLRSEDTAVYYCARENYGSHGGFVYWGQGTLVTVS (SEQ ID NO: 800)
  VH	EVQLVQSGAEVKKPGSSVKVSCKAFGYTFTTYPIEWMRQAHGQGLEWIGNFHPYNDDTKYNEKFKGRVTITV
  	DKSTTTVYMELSSLRSEDTAVYYCARENYGSHGGFVYWGQGTLVTVS (SEQ ID NO: 801)
  VH	EVQLVQSGAEVKKPGSSVKVSCKAFGYTFTTYPIEWMRQAHGQGLEWIGNFHPYNDDTKYNEKFKGRVTITA
  	DKSTSTAYMELSSLRSEDTAVYYCARENYGSHGGFVYWGQGTLVTVS (SEQ ID NO: 802)
  VL	ENVLTQSPFSLSASVGDRVTITCRASSSVISSYLHWYQQKPAKAPKLWIYSTSNLASGVPDRFSGSGSGTSY
  	TLTISSLQPEDFATYYCQQYNGYPLTFGGGTKVEIK (SEQ ID NO: 803)
  VL	ENVLTQSPFSLSASVGDRVTITCRASSSVISSYLHWYQQKPAKAPKLFIYSTSNLASGVPSRFSGSGSGTDY
  	TLTISSLQPEDFATYYCQQYNGYPLTFGGGTKVEIK (SEQ ID NO: 804)
  VL	ENVLTQSPFSLSASVGDRVTITCRASSSVISSYLHWYQQKPAKAPKLWIYSTSNLASGVPDRFSGSGSGTSY
  	TLTISSLQPEDFATYYCQQYNSYPLTFGGGTKVEIK (SEQ ID NO: 805)
  VL	ENVMTQSPFSLSASVGDRVTITCRASSSVISSYLHWYQQKPAKAPKLFIYSTSNLASGVPSRFSGSGSGTDY
  	TLTISSLQPEDFATYYCQQYNGYPLTFGGGTKVEIK (SEQ ID NO: 806)
  VL	ENVMTQSPFSLSASVGDRVTITCRASSSVISSYLHWYQQKPAKAPKLFIYSTSNLASGVPSRFSGSGSGTDY
  	TLTISSLQPEDFATYYCQQYNSYPLTFGGGTKVEIK (SEQ ID NO: 807)
  VL	ENVLTQSPFSLSASVGDRVTITCRASSSVISSYLHWYQQKPAKAPKLFIYSTSNLASGVPSRFSGSGSGTDY
  	TLTISSLQPEDFATYYCQQYNSYPLTFGGGTKVEIK (SEQ ID NO: 808)
  VL	ENVLTQSPGTLSLSPGERATLSCRASSSVISSYLHWYQQKPGQAPRLWIYSTSNLASGVPDRFSGSGSGTSY
  	TLTISRLEPEDFATYYCQQYNGYPLTFGGGTKVEIK (SEQ ID NO: 809)
  VL	ENVLTQSPGTLSLSPGERATLSCRASSSVISSYLHWYQQKPGQAPRLWIYSTSNLASGVPDRFSGSGSGTSY
  	TLTISRLEPEDFATYYCQQYNSYPLTFGGGTKVEIK (SEQ ID NO: 810)

  Group N

  VH	QVQLQQPGAELVKPGASVKLSCKASGYTFTSYYLYWMKQRPGQGLEWIGGVNPSNGGTNFSEKFKSKATLTV
  	DKSSSTAYMQLSSLTSEDSAVYYCTRRDSNYDGGFDYWGQGTTLTVSSAK (SEQ ID NO: 631)
  VL	DIVLTQSPTSLAVSLGQRATISCRASKSVSTSGFSYLHWYQQKPGQPPKLLIFLASNLESGVPARFSGSGSG
  	TDFTLNIHPVEEEDAATYYCQHSWELPLTFGAGTKLELK (SEQ ID NO: 635)

  Group O

  VH	EVQLVESGGGLVQPGGSLRLSCAASGFTFSDYGMHWVRQAPGKGLEWVAYISSGSYTIYSADSVKGRFTISR
  	DNAKNTLYLQMSSLRAEDTAVYYCARRGYGSFYEYYFDYWGQGTTVTVS (SEQ ID NO: 1521)
  VL	QIVLTQSPATLSLSPGERATLSCSASSSVSYMYWYQQKPGQAPRLLIYLTSNRATGIPARFSGSGSGTDYTL
  	TISSLEPEDFAVYYCQQWSSNPFTFGQGTKLEIK (SEQ ID NO: 1522)

  Group P

  VH	EVQLVQSGAEVKKPGESLRISCKGSGYTFTTYWMHWVRQATGQGLEWMGNIYPGTGGSNFDEKFKNRVTITA
  	DKSTSTAYMELSSLRSEDTAVYYCTRWTTGTGAYWGQGTTVTVSS (SEQ ID NO: 1523)
  VH	EVQLVQSGAEVKKPGESLRISCKGSGYTFTTYWMHWIRQSPSRGLEWLGNIYPGTGGSNFDEKFKNRFTISR
  	DNSKNTLYLQMNSLRAEDTAVYYCTRWTTGTGAYWGQGTTVTVSS (SEQ ID NO: 1524)
  VH	EVQLVQSGAEVKKPGESLRISCKGSGYTFTTYWMHWVRQAPGQGLEWMGNIYPGTGGSNFDEKFKNRFTISR
  	DNSKNTLYLQMNSLRAEDTAVYYCTRWTTGTGAYWGQGTTVTVSS (SEQ ID NO: 1525)
  VL	EIVLTQSPATLSLSPGERATLSCKSSQSLLDSGNQKNFLTWYQQKPGQAPRLLIYWASTRESGVPSRFSGSG
  	SGTEFTLTISSLQPDDFATYYCQNDYSYPYTFGQGTKVEIK (SEQ ID NO: 1526)
  VL	DIQMTQSPSSLSASVGDRVTITCKSSQSLLDSGNQKNFLTWYQQKPGQAPRLLIYWASTRESGIPPRFSGSG
  	YGTDFTLTINNIESEDAAYYFCQNDYSYPYTFGQGTKVEIK (SEQ ID NO: 1527)
  VL	EIVLTQSPATLSLSPGERATLSCKSSQSLLDSGNQKNFLTWYQQKPGKAPKLLIYWASTRESGVPSRFSGSG
  	SGTDFTFTISSLQPEDIATYYCQNDYSYPYTFGQGTKVEIK (SEQ ID NO: 1528)
  VL	DIVMTQTPLSLPVTPGEPASISCKSSQSLLDSGNQKNFLTWYQQKPGQAPRLLIYWASTRESGVPSRFSGSG
  	SGTDFTFTISSLEAEDAATYYCQNDYSYPYTFGQGTKVEIK (SEQ ID NO: 1529)
  VL	EIVLTQSPATLSLSPGERATLSCKSSQSLLDSGNQKNFLTWYQQKPGKAPKLLIYWASTRESGVPSRFSGSG
  	SGTDFTFTISSLEAEDAATYYCQNDYSYPYTFGQGTKVEIK (SEQ ID NO: 1530)
  VL	EIVLTQSPDFQSVTPKEKVTITCKSSQSLLDSGNQKNFLTWYQQKPGQAPRLLIYWASTRESGVPSRFSGSG
  	SGTDFTFTISSLEAEDAATYYCQNDYSYPYTFGQGTKVEIK (SEQ ID NO: 1531)
  VL	EIVLTQSPATLSLSPGERATLSCKSSQSLLDSGNQKNFLTWYQQKPGQAPRLLIYWASTRESGVPSRFSGSG
  	SGTDFTFTISSLEAEDAATYYCQNDYSYPYTFGQGTKVEIK (SEQ ID NO: 1532)
  VL	DIQMTQSPSSLSASVGDRVTITCKSSQSLLDSGNQKNFLTWYLQKPGQSPQLLIYWASTRESGVPSRFSGSG
  	SGTDFTFTISSLEAEDAATYYCQNDYSYPYTFGQGTKVEIK (SEQ ID NO: 1533)
  VL	DVVMTQSPLSLPVTLGQPASISCKSSQSLLDSGNQKNFLTWYQQKPGKAPKLLIYWASTRESGVPSRFSGSG
  	SGTDFTFTISSLEAEDAATYYCQNDYSYPYTFGQGTKVEIK (SEQ ID NO: 1534)
  HC	EVQLVQSGAEVKKPGESLRISCKGSGYTFTTYWMHWVRQATGQGLEWMGNIYPGTGGSNFDEKFKNRVTITA
  	DKSTSTAYMELSSLRSEDTAVYYCTRWTTGTGAYWGQGTTVTVSSASTKGPSVFPLAPCSRSTSESTAALGC
  	LVKDYFPEPVTVSWNSGALTSGVHTFPAVLQSSGLYSLSSVVTVPSSSLGTKTYTCNVDHKPSNTKVDKRVE
  	SKYGPPCPPCPAPEFLGGPSVFLFPPKPKDTLMISRTPEVTCVVVDVSQEDPEVQFNWYVDGVEVHNAKTKP
  	REEQFNSTYRVVSVLTVLHQDWLNGKEYKCKVSNKGLPSSIEKTISKAKGQPREPQVYTLPPSQEEMTKNQV
  	SLTCLVKGFYPSDIAVEWESNGQPENNYKTTPPVLDSDGSFFLYSRLTVDKSRWQEGNVFSCSVMHEALHNH
  	YTQKSLSLSLGK (SEQ ID NO: 1535)
  HC	QVQLVQSGAEVKKPGASVKVSCKASGYTFTTYWMHWIRQSPSRGLEWLGNIYPGTGGSNFDEKFKNRFTISR
  	DNSKNTLYLQMNSLRAEDTAVYYCTRWTTGTGAYWGQGTTVTVSSASTKGPSVFPLAPCSRSTSESTAALGC
  	LVKDYFPEPVTVSWNSGALTSGVHTFPAVLQSSGLYSLSSVVTVPSSSLGTKTYTCNVDHKPSNTKVDKRVE
  	SKYGPPCPPCPAPEFLGGPSVFLFPPKPKDTLMISRTPEVTCVVVDVSQEDPEVQFNWYVDGVEVHNAKTKP
  	REEQFNSTYRVVSVLTVLHQDWLNGKEYKCKVSNKGLPSSIEKTISKAKGQPREPQVYTLPPSQEEMTKNQV
  	SLTCLVKGFYPSDIAVEWESNGQPENNYKTTPPVLDSDGSFFLYSRLTVDKSRWQEGNVFSCSVMHEALHNH
  	YTQKSLSLSLGK (SEQ ID NO: 1536)
  HC	EVQLVQSGAEVKKPGESLRISCKGSGYTFTTYWMHWIRQSPSRGLEWLGNIYPGTGGSNFDEKFKNRFTISR
  	DNSKNTLYLQMNSLRAEDTAVYYCTRWTTGTGAYWGQGTTVTVSSASTKGPSVFPLAPCSRSTSESTAALGC
  	LVKDYFPEPVTVSWNSGALTSGVHTFPAVLQSSGLYSLSSVVTVPSSSLGTKTYTCNVDHKPSNTKVDKRVE
  	SKYGPPCPPCPAPEFLGGPSVFLFPPKPKDTLMISRTPEVTCVVVDVSQEDPEVQFNWYVDGVEVHNAKTKP
  	REEQFNSTYRVVSVLTVLHQDWLNGKEYKCKVSNKGLPSSIEKTISKAKGQPREPQVYTLPPSQEEMTKNQV
  	SLTCLVKGFYPSDIAVEWESNGQPENNYKTTPPVLDSDGSFFLYSRLTVDKSRWQEGNVFSCSVMHEALHNH
  	YTQKSLSLSLGK (SEQ ID NO: 1537)
  HC	EVQLVQSGAEVKKPGESLRISCKGSGYTFTTYWMHWVRQAPGQGLEWMGNIYPGTGGSNFDEKFKNRFTISR
  	DNSKNTLYLQMNSLRAEDTAVYYCTRWTTGTGAYWGQGTTVTVSSASTKGPSVFPLAPCSRSTSESTAALGC
  	LVKDYFPEPVTVSWNSGALTSGVHTFPAVLQSSGLYSLSSVVTVPSSSLGTKTYTCNVDHKPSNTKVDKRVE
  	SKYGPPCPPCPAPEFLGGPSVFLFPPKPKDTLMISRTPEVTCVVVDVSQEDPEVQFNWYVDGVEVHNAKTKP
  	REEQFNSTYRVVSVLTVLHQDWLNGKEYKCKVSNKGLPSSIEKTISKAKGQPREPQVYTLPPSQEEMTKNQV
  	SLTCLVKGFYPSDIAVEWESNGQPENNYKTTPPVLDSDGSFFLYSRLTVDKSRWQEGNVFSCSVMHEALHNH
  	YTQKSLSLSLGK (SEQ ID NO: 1538)
  HC	EVQLVQSGAEVKKPGESLRISCKGSGYTFTTYWMHWVRQATGQGLEWMGNIYPGTGGSNFDEKFKNRVTITA
  	DKSTSTAYMELSSLRSEDTAVYYCTRWTTGTGAYWGQGTTVTVSSASTKGPSVFPLAPCSRSTSESTAALGC
  	LVKDYFPEPVTVSWNSGALTSGVHTFPAVLQSSGLYSLSSVVTVPSSSLGTKTYTCNVDHKPSNTKVDKRVE
  	SKYGPPCPPCPAPEFLGGPSVFLFPPKPKDTLMISRTPEVTCVVVDVSQEDPEVQFNWYVDGVEVHNAKTKP
  	REEQFNSTYRVVSVLTVLHQDWLNGKEYKCKVSNKGLPSSIEKTISKAKGQPREPQVYTLPPSQEEMTKNQV
  	SLTCLVKGFYPSDIAVEWESNGQPENNYKTTPPVLDSDGSFFLYSRLTVDKSRWQEGNVFSCSVMHEALHNH
  	YTQKSLSLSLG (SEQ ID NO: 1539)
  HC	EVQLVQSGAEVKKPGESLRISCKGSGYTFTTYWMHWIRQSPSRGLEWLGNIYPGTGGSNFDEKFKNRFTISR
  	DNSKNTLYLQMNSLRAEDTAVYYCTRWTTGTGAYWGQGTTVTVSSASTKGPSVFPLAPCSRSTSESTAALGC
  	LVKDYFPEPVTVSWNSGALTSGVHTFPAVLQSSGLYSLSSVVTVPSSSLGTKTYTCNVDHKPSNTKVDKRVE
  	SKYGPPCPPCPAPEFLGGPSVFLFPPKPKDTLMISRTPEVTCVVVDVSQEDPEVQFNWYVDGVEVHNAKTKP
  	REEQFNSTYRVVSVLTVLHQDWLNGKEYKCKVSNKGLPSSIEKTISKAKGQPREPQVYTLPPSQEEMTKNQV
  	SLTCLVKGFYPSDIAVEWESNGQPENNYKTTPPVLDSDGSFFLYSRLTVDKSRWQEGNVFSCSVMHEALHNH
  	YTQKSLSLSLG (SEQ ID NO: 1540)
  LC	EIVLTQSPATLSLSPGERATLSCKSSQSLLDSGNQKNFLTWYQQKPGQAPRLLIYWASTRESGVPSRFSGSG
  	SGTEFTLTISSLQPDDFATYYCQNDYSYPYTFGQGTKVEIKRTVAAPSVFIFPPSDEQLKSGTASVVCLLNN
  	FYPREAKVQWKVDNALQSGNSQESVTEQDSKDSTYSLSSTLTLSKADYEKHKVYACEVTHQGLSSPVTKSFN
  	RGEC (SEQ ID NO: 1541)
  LC	DIQMTQSPSSLSASVGDRVTITCKSSQSLLDSGNQKNFLTWYQQKPGQAPRLLIYWASTRESGIPPRFSGSG
  	YGTDFTLTINNIESEDAAYYFCQNDYSYPYTFGQGTKVEIKRTVAAPSVFIFPPSDEQLKSGTASVVCLLNN
  	FYPREAKVQWKVDNALQSGNSQESVTEQDSKDSTYSLSSTLTLSKADYEKHKVYACEVTHQGLSSPVTKSFN
  	RGEC (SEQ ID NO: 1542)
  LC	EIVLTQSPATLSLSPGERATLSCKSSQSLLDSGNQKNFLTWYQQKPGKAPKLLIYWASTRESGVPSRFSGSG
  	SGTDFTFTISSLQPEDIATYYCQNDYSYPYTFGQGTKVEIKRTVAAPSVFIFPPSDEQLKSGTASVVCLLNN
  	FYPREAKVQWKVDNALQSGNSQESVTEQDSKDSTYSLSSTLTLSKADYEKHKVYACEVTHQGLSSPVTKSFN
  	RGEC (SEQ ID NO: 1543)
  LC	DIVMTQTPLSLPVTPGEPASISCKSSQSLLDSGNQKNFLTWYQQKPGQAPRLLIYWASTRESGVPSRFSGSG
  	SGTDFTFTISSLEAEDAATYYCQNDYSYPYTFGQGTKVEIKRTVAAPSVFIFPPSDEQLKSGTASVVCLLNN
  	FYPREAKVQWKVDNALQSGNSQESVTEQDSKDSTYSLSSTLTLSKADYEKHKVYACEVTHQGLSSPVTKSFN
  	RGEC (SEQ ID NO: 1544)
  LC	EIVLTQSPATLSLSPGERATLSCKSSQSLLDSGNQKNFLTWYQQKPGKAPKLLIYWASTRESGVPSRFSGSG
  	SGTDFTFTISSLEAEDAATYYCQNDYSYPYTFGQGTKVEIKRTVAAPSVFIFPPSDEQLKSGTASVVCLLNN
  	FYPREAKVQWKVDNALQSGNSQESVTEQDSKDSTYSLSSTLTLSKADYEKHKVYACEVTHQGLSSPVTKSFN
  	RGEC (SEQ ID NO: 1545)
  LC	EIVLTQSPDFQSVTPKEKVTITCKSSQSLLDSGNQKNFLTWYQQKPGQAPRLLIYWASTRESGVPSRFSGSG
  	SGTDFTFTISSLEAEDAATYYCQNDYSYPYTFGQGTKVEIKRTVAAPSVFIFPPSDEQLKSGTASVVCLLNN
  	FYPREAKVQWKVDNALQSGNSQESVTEQDSKDSTYSLSSTLTLSKADYEKHKVYACEVTHQGLSSPVTKSFN
  	RGEC (SEQ ID NO: 1546)
  LC	DIQMTQSPSSLSASVGDRVTITCKSSQSLLDSGNQKNFLTWYLQKPGQSPQLLIYWASTRESGVPSRFSGSG
  	SGTDFTFTISSLEAEDAATYYCQNDYSYPYTFGQGTKVEIKRTVAAPSVFIFPPSDEQLKSGTASVVCLLNN
  	FYPREAKVQWKVDNALQSGNSQESVTEQDSKDSTYSLSSTLTLSKADYEKHKVYACEVTHQGLSSPVTKSFN
  	RGEC (SEQ ID NO: 1547)
  LC	DVVMTQSPLSLPVTLGQPASISCKSSQSLLDSGNQKNFLTWYQQKPGKAPKLLIYWASTRESGVPSRFSGSG
  	SGTDFTFTISSLEAEDAATYYCQNDYSYPYTFGQGTKVEIKRTVAAPSVFIFPPSDEQLKSGTASVVCLLNN
  	FYPREAKVQWKVDNALQSGNSQESVTEQDSKDSTYSLSSTLTLSKADYEKHKVYACEVTHQGLSSPVTKSFN
  	RGEC (SEQ ID NO: 1548)
  LC	EIVLTQSPATLSLSPGERATLSCKSSQSLLDSGNQKNFLTWYQQKPGQAPRLLIYWASTRESGVPSRFSGSG
  	SGTDFTFTISSLEAEDAATYYCQNDYSYPYTFGQGTKVEIKRTVAAPSVFIFPPSDEQLKSGTASVVCLLNN
  	FYPREAKVQWKVDNALQSGNSQESVTEQDSKDSTYSLSSTLTLSKADYEKHKVYACEVTHQGLSSPVTKSFN
  	RGEC (SEQ ID NO: 1834)

  Group Q

  VH	EVQLLESGGGLVQPGGSLRLSCSASGFTFSSYTMNWVRQAPGKGLEWVSGISDTGGNTYYTDSVKGRFTVSR
  	DNSKNTLSLQMNSLRAEDTAVYYCAKDQGGSYPYYFHYWGQGSLVTVSS (SEQ ID NO: 1549)
  VH	EVQLVESGGGLVQPGGSLRLSCAASGFTVSNNYMSWVRQAPGKGLEWVSVIYSGGFTYYTDSVKGRFTISRH
  	NSKNTLYLQMNSLRAEDTAVYYCARYYYDTSDYWTFFDYWGQGTLVTVSS (SEQ ID NO: 1550)
  VH	QVQLVESGGGVVQSGRSLRLSCAASGFTFSSYGMHWVRQAPGKGLEWVAVIWYDGSNIYYSDSVKGRFTISR
  	ANSKNTLYLQMNSLRAEDTAVYYCARPGHWNYFFEYWGQGTLVTVSS (SEQ ID NO: 1551)
  VH	EVQLVESGGGLVQPGGSLRLSCGASGFTFRNYDMHWVRQITGKGLEWVSAIGSAGDTYYPDSVKGRFTISRE
  	NAKNSLYLQMNSLRVGDTAVYYCTRDIHCSSTRCYGMDVWGQGTTVTVSS (SEQ ID NO: 1552)
  VH	EVQLVESGGGLVKPGGSLRLSCAASGFKFSNEWMSWVRQAPGKGLEWVGRIKSKTDGGTTDYAAPVKGRFTI
  	SRDDSKNTLYLQMNSLKTEDTAVYYCTTDQDFWSGYYTGADYYGMDVWGQGTMVTVSS (SEQ ID
  	NO: 1553)
  VH	QMQLQQWGAGLLKPSETLSLTCVVYGGSLNGYYWSWIRQSPGKGLEWIGEIDHSGSTNYNPSLKNRVTMSVD
  	TSKIQFSLKLTSVTVADTAVYYCAREGLLPFDYWGQGTLVTVSS (SEQ ID NO: 1554)
  VH	QLQLQESGPDLVKPSDTLSLTCTVSDDSISSTTYYWAWIRQPPGKGLEWIGSMSYNGNNYYNPSLKSRVAIS
  	AGTSQKQFSLKLTSVTAADTAVYHCARHLGYNGNWYPFDFWGQGILVTVSS (SEQ ID NO: 1555)
  VH	EVQVVESGGGLVEPGRSLRLSCKASGFTFDDYAMHWVRQTPGKALEWVSGINWSGNNIGYADSVKGRFTISK
  	DDAKNSLYLQMNSLRPEDTALYYCTKDISITGTLDAFDVWGQGTMVTVSS (SEQ ID NO: 1556)
  VH	QVQLVESGGGVVQPGRSLRLSCAASGFTFSSYGMHWVRQAPGKGLEWVAIIWSDGDSEYNLDSVKGRFTISR
  	DNSKNTLYLQMNSLRVEDSAVYYCARDRDLEDIWGQGTMVTSS (SEQ ID NO: 1557)
  VH	EVQLLESGGVLVQPGGSLRLSCAASGFTFSNFGMTWVRQAPGKGLEWVSGISGGGRDTYFADSVKGRFTISR
  	DNSKNTLYLQMNSLKGEDTAVYYCVKWGNIYFDYWGQGTLVTVSS (SEQ ID NO: 1558)
  VH	EVQLVESGGGVVRPGGSLRLSCAASGFTFDDYGMSWVRQVPGKGLEWVSGISWNDGKTVYAESVKGRFIISR
  	DNAKNSLYLEMNSLRAEDTALYYCARDWQYLIERYFDYWGQGTLVTVSS (SEQ ID NO: 1559)
  VH	EVQLVESGGGVVRPGGSLRLSCTASGFTFDDYGMSWVRQAPGKGLEWISGIGWTGGRSSYADSVRGRFTISR
  	DNAKNSLYLQMNSLGAEDTALYYCARDRQWLVQWYFDYWGQGTLVTVSS (SEQ ID NO: 1560)
  VH	EVQLVESGGRVVRPGGSLRLSCAASGFTFDDYGMSWVRQLPGKGLEWVAGISWNDGKTVYAESVKGRFIISR
  	DNAKNSLHLEMNSLRAEDTALYYCARDWQYLIDRYFDFWGQGTLVTVSS (SEQ ID NO: 1561)
  VH	EVQLVESGGGLVQPGGSLRLSCAASGFTFDDYAMHWVRQAPGKGLEWVSGIGWSSGSIGYADSVKGRFTISR
  	DNAKNSLYLQMDSLRPEDSALYYCAKAYTFMITLYFDYWGQGTLVTVSS (SEQ ID NO: 1562)
  VH	EVQLVESGGGLVQPGRSLRLSCAASGFTFDDYDMHWVRQAPGKGLEWVSGSGWNRGSLGYADSVKGRFTISR
  	DNAKKSLYLQMNSVRVEDTALYYCAKGFVVVSAAYFDYWGQGTLVTVSS (SEQ ID NO: 1563)
  VH	QVQLVQSGAEVKRPGSSVKVSCKVSGVTFRNFAIIWVRQAPGQGLEWMGGIIPFFSAANYAQSFQGRVTITP
  	DESTSTAFMELASLRSEDTAVYYCAREGERGHTYGFDYWGQGTLVTVSS (SEQ ID NO: 1564)
  VH	EVQLVESGGGLVQSGRSLRLSCAASGFTFDDYAMHWVRQPPGKGLEWVSGINWNRGRTGYADSVKGRFTISR
  	DNAKNSLYLQMNDLRVEDTALYYCAKAEQWLDEGYFDYWGQGTLVTVSS (SEQ ID NO: 1565)
  VH	EVQLVESGGGLVQRGGSLRLSCAASGFSFSSYAMNWVRQAPGKGLEWVSTISDSGGSTYYADSVKGRFTISR
  	DNSKNTLSLQMNSLRAEDTAVYYCAKDQGGSYPYYFHYWGQGTLVTVSS (SEQ ID NO: 1566)
  VH	EVQLVESGGGLVQPGRSLRLSCAASGFTFEDYAMHWVRQAPGKGLEWVSGIGWSNVKIGYADSVKGRFTISR
  	DNVRNSLYLQMNSLRTEDTAFYYCVKAYTSMLTLYFDYWGQGTLVTVSS (SEQ ID NO: 1567)
  VH	QVQLVQSGAEVKRPGASVKVSCKASGYTFTSFYMYWVRQAPGQGLEWMGIINPSDGSTSNAQKFQGRVTMTR
  	DTSTSTVYMELSSLRSEDTAVYYCARRVAGDIFDIWGQGTMTVSS (SEQ ID NO: 1568)
  VH	QVQLQESGPGLVKPSETLSLTCTVSGGSISSYHWNWIRQSPGKGLEWIGYIYYIGSTDYNPSLESRVTISVD
  	TSKNQFSLKLSSVTAADTAVYYCARVPVGATGASDVWGQGTMVTVSS (SEQ ID NO: 1569)
  VH	EVQLVESGGSVVRPGGSLRLSCVVSGFTFEDYGLSWVRQIPGKGLEWVSGISWTGGNTGYADSVKGRFTISR
  	DNAKNSLYLQMNSLRAEDTALYHCTRDRQWLMQWYFDYWGQGTLVTVSS (SEQ ID NO: 1570)
  VH	QVQLVESGGGVVQPGRSLRLSCSASGFTFSAYAMHWVRQAPGKGLEWVAAISYGGSDKYYADSVKGRFTISR
  	DNSKNTLYLQMNSLRTDDTAVYYCAKSAHWNFFFDYWGQGTLVTVSS (SEQ ID NO: 1571)
  VH	EVQLVESGGGLVQPGRSLRLSCVASGFALHDYAMHWVRQVPGKGLEWVSSISWNSGVIGYADSLKGRFTISR
  	DNAKNSLYLQMNSLRAEDTALYYCAKGSGSYYVSWFDPWGQGTLVTVSS (SEQ ID NO: 1572)
  VH	QLQLQESGPGLVQPSETLSLTCTVSGDSISSTAYHWDWIRQPPGKGLEWIGTITYNGNTYFNPSLKSRVTIS
  	VDTSKNQFSLKLLSMTAAETAVFYCARHLGYNSDFFPFDFWGQGTLVTVSS (SEQ ID NO: 1573)
  VH	EVQLVESGGGLVRPGGSLRLSCAASGFTFSTYAMAWVRQTPGKGLEGVSAIGGSGDSTYYVDSVKGRFTISR
  	DNSKSTLFLQMNSLRAEDTAVYYCVKVRNYDGSFDIWGQGTMVTVSS (SEQ ID NO: 1574)
  VL	DIQMTQSPSSLSASVGDRVTITCRASQSISSYLIWYQQKPGTAPKFLIYAASSLQSGVPSRFSGCGSGTDFT
  	LTISSLQPEDFATYYCQQSYSTPPITFGQGTRLEIK (SEQ ID NO: 1575)
  VL	EIVMTQSPATLSVSPGERATLSCRASQSVSSNLAWYQQKPGQAPRLLIYGASTRATGIPARFSGSGSGTEFT
  	LTISSLQSGDFAVYYCQQYNNWPLTFGGGTKVEIN (SEQ ID NO: 1576)
  VL	EIVMTQSPATLSVSPGERATLSCRASQSVSSNLAWYQQKPGQAPRLLIYGASTRATGIPARFSGSGSGTEFT
  	LTISSLQSGDFAVYYCQQYNNWPLTFGGGTKVEIN (SEQ ID NO: 1577)
  VL	DIQMTQSPSSLSASVGDRVTITCRASQSINNYLNWYQQKPGKAPKLLIYTASSLQSGVPSRFSGSGSGTDFT
  	LTISSLQPEDFATYYCQQSYSTPPLTFGQGTQLEIK (SEQ ID NO: 1578)
  VL	DIQMTQSPSSLSASVGDRVTITCRASQSISNYLNWYQQKPGKAPKLLIYAASSLQSGVPSRFSGSGSGTDFT
  	LTISSLQPEDFATYYCQQSYSTPPITFGQGTRLEIK (SEQ ID NO: 1579)
  VL	DIQMTQSPSSLSASVGDRVTITCRASQSISSYLNWYQQKPGKAPKLLIYAASSLQSGVPSRFSGSGSGTDFT
  	LTISSLQPEDFATYYCQQSYSTPPITFGQGTRLEIK (SEQ ID NO: 1580)
  VL	EIVLTQSPGTLSLSPGERVTLSCRASQSVYSNYLAWYQQNPGQAPRLLIYAASNRATGIPDRFSGSGSGTDF
  	TLTISRLEPEDFAVYYCHQYATSPWTFGQGTKVEIK (SEQ ID NO: 1581)
  VL	EIVLTQSPGTLSLSPGERATLSCRASQSVSSSYLAWYQQKPGQAPRLLIYGASSRTTGIPDRFSGSGSGTDF
  	TLTISRLEPEDFAVYYCQQYGSSPWTFGQGTKVEIK (SEQ ID NO: 1582)
  VL	DIQMTQSPISVSASVGDRVTITCRASQGISNWLAWYQQKPGIAPKLLIYSASSLQSGVPSRFRGSGSGTDFT
  	LTIGSLQPEDFATYYCQQAHSFPLTFGGGTKVEIK (SEQ ID NO: 1583)
  VL	DIQMTQSPSSLSASVGDRVTITCRASQGIRNDLGWYQQKPGKAPKRLIYAASNLQSGVPSRFSGSGSGTEFT
  	LTISSLQPEDFATYYCLQHNSYPLTFGGGTKVEIK (SEQ ID NO: 1584)
  VL	DIQMTQSPSSLSASVGDSITITCRASLSINTFLNWYQQKPGKAPNLLIYAASSLHGGVPSRFSGSGSGTDFT
  	LTIRTLQPEDFATYYCQQSSNTPFTFGPGTVVDFR (SEQ ID NO: 1585)
  VL	EIVLTQSPGTLSLSPGERATLSCRASQSVSSSYLAWYQQKPGQAPRLLIYGASSRATGIPDRFSGSGSGTDF
  	TLTISRLEPEDFAVYYCQQYGSSPWTFGQGTKVEIK (SEQ ID NO: 1586)
  VL	DIQMTQSPSSLSASVGDRVTITCRASQSISSYLNWYQQKPGKAPKLLIYAASSLQSGVPSRFSGSGSGTDFT
  	LTISSLQPEDFATYYCQQSYSTPPITFGQGTRLEIK (SEQ ID NO: 1587)
  HC	EVQLLESGGVLVQPGGSLRLSCAASGFTFSNFGMTWVRQAPGKGLEWVSGISGGGRDTYFADSVKGRFTISR
  	DNSKNTLYLQMNSLKGEDTAVYYCVKWGNIYFDYWGQGTLVTVSSASTKGPSVFPLAPCSRSTSESTAALGC
  	LVKDYFPEPVTVSWNSGALTSGVHTFPAVLQSSGLYSLSSVVTVPSSSLGTKTYTCNVDHKPSNTKVDKRVE
  	SKYGPPCPPCPAPEFLGGPSVFLFPPKPKDTLMISRTPEVTCVVVDVSQEDPEVQFNWYVDGVEVHNAKTKP
  	REEQFNSTYRVVSVLTVLHQDWLNGKEYKCKVSNKGLPSSIEKTISKAKGQPREPQVYTLPPSQEEMTKNQV
  	SLTCLVKGFYPSDIAVEWESNGQPENNYKTTPPVLDSDGSFFLYSRLTVDKSRWQEGNVFSCSVMHEALHNH
  	YTQKSLSLSLGK (SEQ ID NO: 1588)
  HC	EVQVVESGGGLVEPGRSLRLSCKASGFTFDDYAMHWVRQTPGKALEWVSGISWSGNNIGYADSVKGRFTISK
  	DDAKNSLYLQMNSLRPEDTALYYCTKDISITGTLDAFDVWGQGTMVTVSSASTKGPSVFPLAPCSRSTSEST
  	AALGCLVKDYFPEPVTVSWNSGALTSGVHTFPAVLQSSGLYSLSSVVTVPSSSLGTKTYTCNVDHKPSNTKV
  	DKRVESKYGPPCPPCPAPEFLGGPSVFLFPPKPKDTLMISRTPEVTCVVVDVSQEDPEVQFNWYVDGVEVHN
  	AKTKPREEQFNSTYRVVSVLTVLHQDWLNGKEYKCKVSNKGLPSSIEKTISKAKGQPREPQVYTLPPSQEEM
  	TKNQVSLTCLVKGFYPSDIAVEWESNGQPENNYKTTPPVLDSDGSFFLYSRLTVDKSRWQEGNVFSCSVMHE
  	ALHNHYTQKSLSLSLGK (SEQ ID NO: 1589)
  HC	EVQLVESGGGLVRPGGSLRLSCAASGFTFSTYAMAWVRQTPGKGLEGVSAIGGSGDSTYYVDSVKGRFTISR
  	DNSKSTLFLQMNSLRAEDTAVYYCVKVRNYDGSFDIWGQGTMVTVSSASTKGPSVFPLAPCSRSTSESTAAL
  	GCLVKDYFPEPVTVSWNSGALTSGVHTFPAVLQSSGLYSLSSVVTVPSSSLGTKTYTCNVDHKPSNTKVDKR
  	VESKYGPPCPPCPAPEFLGGPSVFLFPPKPKDTLMISRTPEVTCVVVDVSQEDPEVQFNWYVDGVEVHNAKT
  	KPREEQFNSTYRVVSVLTVLHQDWLNGKEYKCKVSNKGLPSSIEKTISKAKGQPREPQVYTLPPSQEEMTKN
  	QVSLTCLVKGFYPSDIAVEWESNGQPENNYKTTPPVLDSDGSFFLYSRLTVDKSRWQEGNVFSCSVMHEALH
  	NHYTQKSLSLSLGK (SEQ ID NO: 1590)
  HC	QVQLVQSGAEVKRPGSSVKVSCKVSGVTFRNFAIIWVRQAPGQGLEWMGGIIPFFSAANYAQSFQGRVTITP
  	DESTSTAFMELASLRSEDTAVYYCAREGERGHTYGFDYWGQGTLVTVSSASTKGPSVFPLAPCSRSTSESTA
  	ALGCLVKDYFPEPVTVSWNSGALTSGVHTFPAVLQSSGLYSLSSVVTVPSSSLGTKTYTCNVDHKPSNTKVD
  	KRVESKYGPPCPPCPAPEFLGGPSVFLFPPKPKDTLMISRTPEVTCVVVDVSQEDPEVQFNWYVDGVEVHNA
  	KTKPREEQFNSTYRVVSVLTVLHQDWLNGKEYKCKVSNKGLPSSIEKTISKAKGQPREPQVYTLPPSQEEMT
  	KNQVSLTCLVKGFYPSDIAVEWESNGQPENNYKTTPPVLDSDGSFFLYSRLTVDKSRWQEGNVFSCSVMHEA
  	LHNHYTQKSLSLSLGK (SEQ ID NO: 1591)
  LC	DIQMTQSPSSLSASVGDSITITCRASLSINTFLNWYQQKPGKAPNLLIYAASSLHGGVPSRFSGSGSGTDFT
  	LTIRTLQPEDFATYYCQQSSNTPFTFGPGTVVDFRRTVAAPSVFIFPPSDEQLKSGTASVVCLLNNFYPREA
  	KVQWKVDNALQSGNSQESVTEQDSKDSTYSLSSTLTLSKADYEKHKVYACEVTHQGLSSPVTKSFNRGEC
  	(SEQ ID NO: 1592)
  LC	DIQMTQSPISVSASVGDRVTITCRASQGISNWLAWYQQKPGIAPKLLIYSASSLQSGVPSRFRGSGSGTDFT
  	LTIGSLQPEDFATYYCQQAHSFPLTFGGGTKVEIKRTVAAPSVFIFPPSDEQLKSGTASVVCLLNNFYPREA
  	KVQWKVDNALQSGNSQESVTEQDSKDSTYSLSSTLTLSKADYEKHKVYACEVTHQGLSSPVTKSFNRGEC
  	(SEQ ID NO: 1593)
  LC	EIVLTQSPGTLSLSPGERATLSCRASQSVSSSYLAWYQQKPGQAPRLLIYGASSRATGIPDRFSGSGSGTDF
  	TLTISRLEPEDFAVYYCQQYGSSPWTFGQGTKVEIKRTVAAPSVFIFPPSDEQLKSGTASVVCLLNNFYPRE
  	AKVQWKVDNALQSGNSQESVTEQDSKDSTYSLSSTLTLSKADYEKHKVYACEVTHQGLSSPVTKSFNRGEC
  	(SEQ ID NO: 1594)
  LC	DIQMTQSPSSLSASVGDRVTITCRASQSISSYLNWYQQKPGKAPKLLIYAASSLQSGVPSRFSGSGSGTDFT
  	LTISSLQPEDFATYYCQQSYSTPPITFGQGTRLEIKRTVAAPSVFIFPPSDEQLKSGTASVVCLLNNFYPRE
  	AKVQWKVDNALQSGNSQESVTEQDSKDSTYSLSSTLTLSKADYEKHKVYACEVTHQGLSSPVTKSFNRGEC
  	(SEQ ID NO: 1595)

  Group R

  VH	EVKLVESGGGLVKPGGSLKLSCAASGFTFSSYGMSWLRQTPEKRLEWVATMSGGGRDIYYPDSMKGRFTISR
  	DNAKNNLYLQMSSLRSEDTALYYCARQYYDDWFAYWGQGTLVTVSA (SEQ ID NO: 1719)
  VH	QVQLKQSGPGLVQPSQNLSVTCTVSGFSLTTYGVHWVRQSPGKGLEWLGVIWSGGSTDYNAAFISRLTISKD
  	NARSQVFFKMNSLQVNDTAMYYCAREKSVYGNYVGAMDYWGQGTSVTVSS (SEQ ID NO: 1720)
  VH	EVKLVESGGGLVKPGGSLKLSCGASGFTFSSYGMSWVRQTPEKRLEWVATISGGGRDIYYPDSVKGRLTISR
  	DNAKNNLYLQMSSLRSEDTALYYCVRQYYDDWFAYWGQGTLVTVSA (SEQ ID NO: 1721)
  VH	DVQLQESGPGLVKPSQSLSLTCTVTGYSITSDYAWNWIRQFPGNQLEWMAYISYSGYTSYNPSLKSRISITR
  	DTSKNQFFLQLNSVTTEDTATYYCARSLDYDYGTMDYWGQGTSVTVSS (SEQ ID NO: 1722)
  VH	EVKLVESGGGLVKPGGSLKLSCAASGFAFRSYDMSWVRQTPEKILEWVATISGGGSYTYYQDSVKGRFTISR
  	DNARNTLYLQMSSLRSEDTALYYCASPYGPYFDYWGQGTTLTVSS (SEQ ID NO: 1723)
  VH	DVQLQESGPGLVKPSQSLSLTCTVTGYSITSDYAWNWIRQFPGNQLEWMAYISYSGYTSYNPSLKSRISITR
  	DTSRNQFFLQLNSVTTEDTATYYCARSLDYDYGTMDYWGQGTSVTVSS (SEQ ID NO: 1724)
  VH	EVKLVESGGGLVKPGGSLKLSCSASGFSFSYYDMSWVRQTPEKGLEWVATISGGGRNTYFIDSVKGRFTISR
  	DNVKNNLYLLMSSLRSEDTALYYCASPYEGAVDFWGQGTSVTVSS (SEQ ID NO: 1725)
  VH	EVKLVESGGGLVKPGGSLKLSCAASGFTFSSYGMSWVRQTPEKRLEWATISGGGRDTYYLDSVKGRFTISRD
  	NAKNNLYLQMSSLRSEDTALYYCVRQYYDDWFAYWGQGTLVSNSA (SEQ ID NO: 1726)
  VH	QVQLQQSGDELVRPGTSVKMSCKAAGYTFTNNWIGWVKQRPGHGLEWIGDFYPGGGYTNYNEKFKGKATLTA
  	DTSSSTAYMQLSSLTSEDSAIYYCARGYGTNYWYFDVWGAGTTVTVSS (SEQ ID NO: 1727)
  VH	QIHLVQSGPELKKPGETVKISCKASGYTFTNFGMNWVKQAPGKGLKWMGWISGYTREPTYAADFKGRFAISL
  	ETSASTAYLQINDLKNEDMATYFCARDVFDYWGQGTTLTVSS (SEQ ID NO: 1728)
  VH	QIQLVQSGSELKKPGASVKVSCKASGYTFTNFGMNWVRQAPGQGLKWMGWISGYTREPTYAADFKGRFVISL
  	DTSVSTAYLQISSLKAEDTAVYYCARDVFDYWGQGTLVTVSS (SEQ ID NO: 1729)
  VH	QVQLQESGPGLVKPSQTLSLTCTVSGYSISSDYAWNWIRQPPGKGLEWMAYISYSGYTSYNPSLKSRITISR
  	DTSKNQFSLKLSSVTAADTAVYYCARSLDYDYGTMDYWGQGTLVTVSS (SEQ ID NO: 1730)
  VL	DIVLTQTPATLSVTPGDSVSLSCRASQSISNNLHWYQQKSHESPRLLIKYASQSISGIPSRFSGSGSGTDFT
  	LNINSVETEDFGMYFCQQSNSWPLTFGAGTKLELKR (SEQ ID NO: 1731)
  VL	SIVMTQTPKFLLVSAGDRVTITCKASQSVSDDVAWYQQKPGQSPKLLIYYAFNRYTGVPDRFTGSGYGTDFT
  	FTISTVQSEDLAVYFCQQDYRSPWTFGGGTKLEIKR (SEQ ID NO: 1732)
  VL	DIVLTQSPATLSVTPGDSVSLSCRASQSISNDLHWYQQKSHESPRLLIKYVSQSISGIPSRFSGSGSGTDFT
  	LSINSVETEDFGMYFCQQSDSWPLTFGAGTKLELKR (SEQ ID NO: 1733)
  VL	QIVLSQSPAILSASPGEKVTMTCRANSSVSSMHWYQQKPGSSPEPWIYAISNLAFGVPTRFSGSGSGTSYSL
  	TISRVEAEDAATYFCQQWSSRPPTFGGGTKLEIKR (SEQ ID NO: 1734)
  VL	DIQMNQSPSSLSASLGDTITITCHASQSINVWLSWYQQKPGNIPKLLIYRASNLHTGVPSRFSGSGSGTGFT
  	LTISSLQPDDIATYYCQQGQSYPWTFGGGTKLEIKR (SEQ ID NO: 1735)
  VL	QIVLSQSPAILSASPGEKVTMTCRANSSVSSMHWYQQKPGSSPEPWIYAISNLAFGVPARFSGSGSGTSYSL
  	TISRVEAEDAATYFCQQWNSRPPTFGGGTKLEIKR (SEQ ID NO: 1736)
  VL	DIVMTQSHKVMSTSVGDRVSITCKASQDVDNAVAWYQQNPGQSPKLLIKWASTRHHGVPDRFTGSGSGTDFT
  	LTISTVQSEDLADFFCQQYSTFPYTFGGGTKLEIKR (SEQ ID NO: 1737)
  VL	DIVLTQTPATLSVTPGDSVSLSCRASQSLSNNLHWYQQKSHESPRLLIKYASQSISGIPSRFSGSGSGTDFT
  	LSINSVETEDFGMYFCQQSNSWPLTFGAGTKLEMKR (SEQ ID NO: 1738)
  VL	NIVMTQTPKILFISAGDRVTITCKASQSVSNDVAWYQQKPGQSPKLLIYYAFTRYIGVPDRFTGSGYGTDFT
  	FTISTVQAEDLAVYFCQQDYSSPYTFGGGTKLEIKR (SEQ ID NO: 1739)
  VL	DIVLTQSPASLAVSLGQRATISCRASESVDNYGYSFMNWFQQKPGQPPKLLIYRASNLESGIPARFSGSGSR
  	TNFTLTINPVEADDVATYFCQQSNADPTFGGGTNLEIKR (SEQ ID NO: 1740)
  VL	DIVLTQSPASLAVSPGQRATITCRASESVDNYGYSFMNWFQQKPGQPPKLLIYRASNLESGVPARFSGSGSR
  	TDFTLTINPVEANDTANYYCQQSNADPTFGQGTKLEIK (SEQ ID NO: 1741)
  VL	EIVLTQSPATLSLSPGERATLSCRANSSVSSMHWYQQKPGQSPEPWIYAISNLAFGVPARFSGSGSGTDYTL
  	TISSLEPEDFAVYYCQQWSSRPPTFGQGTKLEIK (SEQ ID NO: 1742)

  Group S

  VH	QVQLVQSGSEVKKSGSSVKVSCKTSGGTFSITNYAINWVRQAPGQGLEWMGGILPIFGAAKYAQKFQDRVTI
  	TADESTNTAYLELSSLTSEDTAMYYCARGKRWLQSDLQYWGQGTLVTVSS (SEQ ID NO: 1743)
  VL	QPVLTQPASVSGSPGQSITISCTGSSSDVGSYDLVSWYQQSPGKVPKLLIYEGVKRPSGVSNRFSGSKSGNT
  	ASLTISGLQAEDEADYYCSSYAGTRNFVFGGGTQLTVL (SEQ ID NO: 1744)

  Group T

  VH	QVQLVQSGAEVKKPGASVKVSCKASGYTFTNYYMYWVKQAPGQGLEWIGGINPSNGGTNYNEKFKNKATLTA
  	DKSTSTAYMELSSLRSEDTAVYYCTRRDYRYDMGFDYWGQGTTVTVSS (SEQ ID NO: 1745)
  VH	QVQLVQSGAEVKKPGASVKVSCKASGYTFTSYYMYWVRQAPGQGLEWMGGVNPSNGGTNFNEKFKSRVTITA
  	DKSTSTAYMELSSLRSEDTAVYYCARRDYRYDMGFDYWGQGTTVTVSS (SEQ ID NO: 1746)
  VH	EVQLQQSGPELVKPGASVKISCKASGYTFTNYYMYWVKQSHGKSLEWIGGINPSNGGTNYNEKFKNKATLTV
  	DKSSSTAYMELNSLTSEDSAVYYCARRDYRYDMGFDYWGAGTTVTVSS (SEQ ID NO: 1747)
  VH	EVQLQQSGPVLVKPGASVKMSCKASGYTFTSYYMYWVKQSHGKSLEWIGGVNPSNGGTNFNEKFKSKATLTV
  	DKSSSTAYMELNSLTSEDSAVYYCARRDYRYDMGFDYWGQGTTLTVSS (SEQ ID NO: 1748)
  VL	EIVLTQSPATLSLSPGERATISCRASKGVSTSGYSYLHWYQQKPGQAPRLLIYLASYLESGVPARFSGSGSG
  	TDFTLTISSLEPEDFATYYCQHSRELPLTFGTGTKVEIK (SEQ ID NO: 1749)
  VL	QIVLTQSPAIMSASPGEKVTMTCRASKGVSTSGYSYLHWYQQKPGSSPRLLIYLASYLESGVPVRFSGSGSG
  	TSYSLTISRMEAEDAATYYCQHSRELPLTFGTGTRLEIK (SEQ ID NO: 1750)

  Group U

  VH	QVQLQQSGAELMKPGASVKMSCKTTGYIFSSYWIGWVKQRPGHGLEWIGKIFPGSGSADYNENFKGKATFTV
  	DTSSNTAYMQLSSLTSEDSAVYYCARGYGNYLYFDVWGAGTTVTVSS (SEQ ID NO: 619)
  VH	DVQLQESGPGLVKPSQSLSLTCTVTGHSITSDYAWNWIRQFPGNKLEWMGYISYSGRTSYNPSLTSRISITR
  	DTSKNQFFLQLNSVTTEDTATYYCARGYALDYWGQGTSVTVSS (SEQ ID NO: 1835)
  VH	EVKLVESGGGLVSPGGSLKLSCAASGFTFSTFGMSWVRQTPEKRLEWVATISGGGSDTYYPDSVQGRFIISR
  	YNAKNNLYLQMNSLRPEDTALYYCARQGYDVYSWFAYWGQGTLVTVSA (SEQ ID NO: 1836)
  VH	EVKLVESGGGLVKPGGSLKLSCAASGFTFSTYGMSWVRQTPEKRLQWVATISGGGSNTYYSDSVKGRFTISR
  	DNAKNNLYLQMSSLRSEDTALYYCARQRDSAWFASWGQGTLVTVSA (SEQ ID NO: 1837)
  VH	EVQLVESGGGLVKPGGSLRLSCAASGFTFSTFGMSWVRQAPGKGLEWVSTISGGGSDTYYPDSVQGRFTISR
  	DNAKNSLYLQMNSLRAEDTAVYYCARQGYDVYSWFAYWGQGTLVTVSS (SEQ ID NO: 1838)
  VH	EVQLVESGGGLVQPGGSLRLSCAASGFTFSTFGMSWVRQAPGKGLEWVATISGGGSDTYYPDSVQGRFTISR
  	DNAKNSLYLQMNSLRAEDTAVYYCARQGYDVYSWFAYWGQGTLVTVSS (SEQ ID NO: 1839)
  VH	EVQLVESGGGLVKPGGSLRLSCAASGFTFSTYGMSWVRQAPGKGLEWVATISGGGSNTYYSDSVKGRFTISR
  	DDSKNTLYLQMNSLKTEDTAVYYCARQRDSAWFASWGQGTLVTVSS (SEQ ID NO: 1840)
  VH	EVQLVQSGAEVKKPGASVKVSCKASGYRFPHYGISWVRQAPGQGLEWMGWISAYNGNTNYAQKLQGRVTMTT
  	DTSTNTAYMELRSLRSDDTAVYYCARDVDYGTGSGYWGQGTLVTVSS (SEQ ID NO: 1841)
  VH	EVQLVQSGAEVKKPGASVKVSCKASGYRFTRQGISWVRQAPGQGLEWMGWISAYNGNTKYAQKLQGRVTMTT
  	DTSTNTAYMELRSLRSDDTAVYYCARDVDYGSGSGYWGQGTLVTVSS (SEQ ID NO: 1842)
  VH	EVQLVQSGAEVKKPGASVKVSCKASGYRFSTFGISWVRQAPGQGLEWMGWISAYNGNTNYAQKLQGRVTMTT
  	DTSTNTAYMELRSLRSDDTAVYYCARDVDYSSGSGYWGQGTLVTVSS (SEQ ID NO: 1843)
  VH	EVQLVQSGAEVKKPGASVKVSCKASGYRFTRYGISWVRQAPGQGLEWMGWVSAHNGNTNYAQKLQGRVTMTT
  	DTSTNTAYMELRSLRSDDTAVYYCARDADYGSGSGYWGQGTLVTVSS (SEQ ID NO: 1844)
  VH	EVQLVQSGAEVKKPGASVKVSCKASGYRFPHYGISWVRQAPGQGLEWMGWISAYNGNTNYAQKLQGRVTMTT
  	DTSTNTAYMELRSLRSDDTAVYYCARDAEYGSGSGYWGQGTLVTVSS (SEQ ID NO: 1845)
  VH	EVQLVQSGAEVKKPGASVKVSCKASGYRFTWYGISWVRQAPGQGLEWMGWISAYNGNTNYAQKLQGRVTMTT
  	DTSTNTAYMELRSLRSDDTAVYYCARDSEYSSGSGYWGQGTLVTVSS (SEQ ID NO: 1846)
  VH	EVQLVQSGAEVKKPGASVKVSCKASGYRFETYGISWVRQAPGQGLEWMGWISAYNGNTNYAQKLQGRVTMTT
  	DTSTNTAYMELRSLRSDDTAVYYCARDAEYSLGSGYWGQGTLVTVSS (SEQ ID NO: 1847)
  VH	EVQLVQSGAEVKKPGASVKVSCKASGYRFRQYGISWVRQAPGQGLEWMGWISAYNGNTNYAQKLQGRVTMTT
  	DTSTNTAYMELRSLRSDDTAVYYCARDAEYGSGSGYWGQGTLVTVSS (SEQ ID NO: 1848)
  VH	EVQLVQSGAEVKKPGASVKVSCKASGYRFTWYGISWVRQAPGQGLEWMGWISAYNGNTNYAQKLQGRVTMTT
  	DTSTNTAYMELRSLRSDDTAVYYCARDSEYRSGSGYWGQGTLVTVSS (SEQ ID NO: 1849)
  VH	EVQLVQSGAEVKKPGASVKVSCKASGYRFRQYGISWVRQAPGQGLEWMGWISAYNGNTNYAQKLQGRVTMTT
  	DTSTNTAYMELRSLRSDDTAVYYCARDAEYRSGSGYWGQGTLVTVSS (SEQ ID NO: 1850)
  VH	EVQLVQSGAEVKKPGASVKVSCKASGYRFTRYGISWVRQAPGQGLEWMGWVSAHNGNTNYAQKLQGRVTMTT
  	DTSTNTAYMELRSLRSDDTAVYYCARDADYRSGSGYWGQGTLVTVSSS (SEQ ID NO: 1851)
  VH	EVQLVQSGAEVKKPGASVKVSCKASGYRFPHYGISWVRQAPGQGLEWMGWISAYNGNTNYAQKLQGRVTMTT
  	DTSTNTAYMELRSLRSDDTAVYYCARDVDYRTGSGYWGQGTLVTVSS (SEQ ID NO: 1852)
  VH	EVQLVQSGAEVKKPGASVKVSCKASGYRFSTFGISWVRQAPGQGLEWMGWISAYNGNTNYAQKLQGRVTMTT
  	DTSTNTAYMELRSLRSDDTAVYYCARDVDYRSGSGYWGQGTLVTVSS (SEQ ID NO: 1853)
  VH	EVQLVQSGAEVKKPGASVKVSCKASGYRFTRQGISWVRQAPGQGLEWMGWISAYNGNTKYAQKLQGRVTMTT
  	DTSTNTAYMELRSLRSDDTAVYYCARDVDYRSGSGYWGQGTLVTVSS (SEQ ID NO: 1854)
  VH	EVQLVQSGAEVKKPGASVKVSCKASGYRFPHYGISWVRQAPGQGLEWMGWISAYNGNTNYAQKLQGRVTMTT
  	DTSTNTAYMELRSLRSDDTAVYYCARDAEYRSGSGYWGQGTLVTVSS (SEQ ID NO: 1855)
  VH	EVQLVQSGAEVKKPGASVKVSCKASGYRFETYGISWVRQAPGQGLEWMGWISAYNGNTNYAQKLQGRVTMTT
  	DTSTNTAYMELRSLRSDDTAVYYCARDAEYRLGSGYWGQGTLVTVSS (SEQ ID NO: 1869)
  VL	NIVMTQTPKFLLVSAGDRITITCKASQSVSDDVAWYQQKPGQSPKLLISYAFKRYIGVPDRFTGSGYGTDFT
  	FTISTVQAEDLAVYFCQQNYNSPYTFGGGTKLELKR (SEQ ID NO: 1856)
  VL	QIVLSQSPAILSASPGEKVTMTCRTSSSVNYMHWFQQKPGSSPKPWIYATSKLASGVPARFSGSGSGTSYSL
  	TISRVEAEDAATYFCQQWISDPWTFGGGTKLEIK (SEQ ID NO: 1857)
  VL	SYELTQPPSVSVSPGQTARITCSGDALTTQYAYWYQQKPGQAPVMVIYKDTERPSGIPERFSGSSSGTKVTL
  	TISGVQAEDEADYYCQSADNSITYRVFGGGTKVTVL (SEQ ID NO: 1858)
  VL	SYELTQPPSVSVSPGQTARITCSGDALSEQYAYWYQQKPGQAPVMVIYKDTERPSGIPERFSGSSSGTKVTL
  	TISGVQAEDEADYYCQSADNSITYRVFGGGTKVTVL (SEQ ID NO: 1859)
  VL	SYELTQPPSVSVSPGQTARITCSGDALPKQYAYWYQQKPGQAPVMVIYKDTERPSGIPERFSGSSSGTKVTL
  	TISGVQAEDEADYYCQSADNSITYRVFGGGTKVTVL (SEQ ID NO: 737)
  VL	SYELTQPPSVSVSPGQTARITCSGDALPMQYGYWYQQKPGQAPVMVLYKDTERPSGIPERFSGSSSGTKVTL
  	TISGVQAEDEDYYCQSDNSITYRVFGGGTKVTVL (SEQ ID NO: 1860)
  VL	SYELTQPPSVSVSPGQTARITCSGDALPMQYGYWYQQKPGQAPVMVIYKDTERPSGIPERFSGSSSGTKVTL
  	TISGVQAEDEADYYCQSADNSITYRVFGGGTKVTVL (SEQ ID NO: 1861)
  VL	DIILTQSPASLAVSLGQRAAISCRASESVDNSGISFMSWFQQKPGQPPKLLIYTASNQGSGVPARFSGSGSG
  	TEFSLNIHPMEEDDTAMYFCQQSKEVPWTFGGGTKLEIR (SEQ ID NO: 1862)
  VL	DIVLTQSPASLAVSLGQRATISCRASENVDDYGVSFMNWFQQKPGQPPKLLIYPASNQGSGVPARFSGSGSG
  	TDFSLNIHPMEEDDTAMYFCQQSKEVPWTFGGGTKLEIK (SEQ ID NO: 1863)
  VL	DIQLTQSPSFLSASVGDRVTITCRASESVDNSGISFMSWYQQKPGKAPKLLIYTASNQGSGVPSRFSGSGSG
  	TEFTLTISSLQPEDFATYYCQQSKEVPWTFGQGTKVEIK (SEQ ID NO: 1864)
  VL	EIVLTQSPATLSLSPGERATLSCRASESVDNSGISFMSWYQQKPGQAPRLLIYTASNQGSGIPARFSGSGSG
  	TDFTLTISSLEPEDFAVYYCQQSKEVPWTFGQGTKVEIK (SEQ ID NO: 1865)
  VL	EIVLTQSPATLSLSPGERATLSCRASENVDDYGVSFMNWYQQKPGQAPRLLIYPASNQGSGIPARFSGSGSG
  	TDFTLTISSLEPEDFAVYYCQQSKEVPWTFGQGTKVEIK (SEQ ID NO: 1866)
  VL	EIVLTQSPGTLSLSPGERATLSCRASENVDDYGVSFMNWYQQKPGQAPRLLIYPASNQGSGIPDRFSGSGSG
  	TDFTLTISRLEPEDFAVYYCQQSKEVPWTFGQGTKVEIK (SEQ ID NO: 1867)
  VL	DIVMTQSPDSLAVSLGERATINCRASENVDDYGVSFMNWYQQKPGQPPKLLIYPASNQGSGVPDRFSGSGSG
  	TDFTLTISSLQAEDVAVYYCQQSKEVPWTFGGGTKLEIK (SEQ ID NO: 1868)

  Group V

  VH	QVQLVQSGAEVKKPGASVKVSCKASGYTFTSYWINWVRQAPGQGLEWMGNIYPGSSLTNYNEKFKNRVTMTR
  	DTSTSTVYMELSSLRSEDTAVYYCARLLTGTFAYWGQGTLVTVSS (SEQ ID NO: 1870)
  VH	QVQLVQSGAEVKKPGASVKVSCKASGYTFTSYWINWVRQAPGQGLEWMGNIYPGSSLTNYNEKFKNRVTMTR
  	DTSTSTVYMELSSLRSEDTAVYYCARLSTGTFAYWGQGTLVTVSS (SEQ ID NO: 1871)
  VH	QVQLVQSGAEVKKPGASVKVSCKASGYTFTSYWINWVRQAPGQGLEWMGNIYPGSSITNYNEKFKNRVTMTR
  	DTSTSTVYMELSSLRSEDTAVYYCARLTTGTFAYWGQGTLVTVSS (SEQ ID NO: 1872)
  VH	QVQLVQSGAEVKKPGASVKVSCKASGYTFTSYWINWVRQAPGQGLEWMGNIWPGSSLTNYNEKFKNRVTMTR
  	DTSTSTVYMELSSLRSEDTAVYYCARLLTGTFAYWGQGTLVTVSS (SEQ ID NO: 1873)
  VH	DIVMTQSPDSLAVSLGERATINCKSSQSLWDSGNQKNFLTWYQQKPGQPPKLLIYWTSTRESGVPDRFSGSG
  	SGTDFTLTISSLQAEDVAVYYCQNDYFYPLTFGGGTKVEIK (SEQ ID NO: 1874)
  VL	DIVMTQSPDSLAVSLGERATINCKSSQSLWDSGNQKNFLTWYQQKPGQPPKLLIYWTSYRESGVPDRFSGSG
  	SGTDFTLTISSLQAEDVAVYYCQNDYFYPLTFGGGTKVEIK (SEQ ID NO: 1875)
  VL	DIVMTQSPDSLAVSLGERATINCKSSQSLWDSGNQKNFLTWYQQKPGQPPKLLIYWTSYRESGVPDRFSGSG
  	SGTDFTLTISSLQAEDVAVYYCQNDYFYPHTFGGGTKVEIK (SEQ ID NO: 1876)
  VL	DIVMTQSPDSLAVSLGERATINCKSSQSLWDSTNQKNFLTWYQQKPGQPPKLLIYWTSTRESGVPDRFSGSG
  	SGTDFTLTISSLQAEDVAVYYCQNDYFYPLTFGGGTKVEIK (SEQ ID NO: 1877)
  HC	QVQLVQSGAEVKKPGASVKVSCKASGYTFTSYWINWVRQAPGQGLEWMGNIYPGSSLTNYNEKFKNRVTMTR
  	DTSTSTVYMELSSLRSEDTAVYYCARLSTGTFAYWGQGTLVTVSSASTKGPSVFPLAPCSRSTSESTAALGC
  	LVKDYFPEPVTVSWNSGALTSGVHTFPAVLQSSGLYSLSSVVTVPSSSLGTKTYTCNVDHKPSNTKVDKRVE
  	SKYGPPCPPCPAPEFLGGPSVFLFPPKPKDTLMISRTPEVTCVVVDVSQEDPEVQFNWYVDGVEVHNAKTKP
  	REEQFNSTYRVVSVLTVLHQDWLNGKEYKCKVSNKGLPSSIEKTISKAKGQPREPQVYTLPPSQEEMTKNQV
  	SLTCLVKGFYPSDIAVEWESNGQPENNYKTTPPVLDSDGSFFLYSRLTVDKSRWQEGNVFSCSVMHEALHNH
  	YTQKSLSLSLGK (SEQ ID NO: 1878)
  HC	QVQLVQSGAEVKKPGASVKVSCKASGYTFTSYWINWVRQAPGQGLEWMGNIYPGSSLTNYNEKFKNRVTMTR
  	DTSTSTVYMELSSLRSEDTAVYYCARLSTGTFAYWGQGTLVTVSSASTKGPSVFPLAPCSRSTSESTAALGC
  	LVKDYFPEPVTVSWNSGALTSGVHTFPAVLQSSGLYSLSSVVTVPSSSLGTKTYTCNVDHKPSNTKVDKRVE
  	SKYGPPCPPCPAPEFLGGPSVFLFPPKPKDTLMISRTPEVTCVVVDVSQEDPEVQFNWYVDGVEVHNAKTKP
  	REEQFNSTYRVVSVLTVLHQDWLNGKEYKCKVSNKGLPSSIEKTISKAKGQPREPQVYTLPPSQEEMTKNQV
  	SLTCLVKGFYPSDIAVEWESNGQPENNYKTTPPVLDSDGSFFLYSRLTVDKSRWQEGNVFSCSVMHEALHNH
  	YTQKSLSLSLG (SEQ ID NO: 1879)
  LC	DIVMTQSPDSLAVSLGERATINCKSSQSLWDSGNQKNFLTWYQQKPGQPPKLLIYWTSYRESGVPDRFSGSG
  	SGTDFTLTISSLQAEDVAVYYCQNDYFYPHTFGGGTKVEIKRGTVAAPSVFIFPPSDEQLKSGTASVVCLLN
  	NFYPREAKVQWKVDNALQSGNSQESVTEQDSKDSTYSLSSTLTLSKADYEKHKVYACEVTHQGLSSPVTKSF
  	NRGEC (SEQ ID NO: 1880)

  Group W

  VH	EVQLQESGPELVRPGASVKMSCKASGYTFTSYWMHWVKQRPGQGLEWIGMIDPSNSETSLNQKFKDKATLNV
  	DKSTNTAYMQLSSLTSEDSAVYYCARSRGNYAYEMDYWGQGTSVTVSS (SEQ ID NO: 1972)
  VH	EVQLQESGPELVRPGASVKMSCKASGYTFTSYWMHWVKQRPGQGLEWIGMIEPSSSETSLNQKFKDKATLNV
  	DKSSNTAYMQLSSLTSEDSAVYYCARSRGNYAYEMDYWGQGTSVTVSS (SEQ ID NO: 1973)
  VH	EVQLQESGPELVRPGASVKMSCKASGYTFTSYWMHWVKQRPGQGLEWIGMIDPYSSETSLNQKFKDKATLNV
  	DKISNTAYMQLSSLTSEDSAVYFCARSRGNYAYDMDYWGQGTSVTVSS (SEQ ID NO: 1974)
  VH	EVQLQESGPELVRPGASVKMSCKASGYTFTSYWMHWVKQRPGQGLEWIGMIDPSNSETSLNQKFKDKATLNV
  	DKSSKTAYMQLSSLTSEDSAVYYCARSRGNYAYDMDYWGQGTSVTVSS (SEQ ID NO: 1975)
  VH	EVQLQESGAELVMPGASVKMSCKASGYTFTDYWMHWVKQRPGQGLEWIGAIDTSDSYTSYHQNFKGKATLTE
  	DESSSTAYMQLSSLTSEDSAIYYCARRDYGGFGYWGQGTTLTVSS (SEQ ID NO: 1976)
  VH	EVQLQESGPELVKPGASVKIPCKASGYTFTDYNMDWVKKSHGKSLEWIGDIDPNNGGTIYNQKFKGKATLTV
  	DKSSRTAYMELRSLTSEDTAVYYCARWRSSMDYWGQGTSVTVSS (SEQ ID NO: 1977)
  VH	EVQLQESGPELVKPGASVKIPCRASGYIFTDYNMDWVKQSHGKSLEWIGDIDPNNGGTIYNQKFKDKTTLTV
  	DKSSRTAYMELRSLTSEDTAVYYCARWRSSMDYWGQGTSVTVSS (SEQ ID NO: 1978)
  VH	EVQLQESGPELVKPGASVKIPCKASGYTFTDYNMDWVKQNHGKSLEWIGDIDPNNGDTIYNQKFKGKATLTV
  	DKSSRTAYMELRSLTSEDTAVYYCARWRSSMDYWGQGTSVTVSS (SEQ ID NO: 1979)
  VH	EVQLQESGPELVKPGASVKIPCKASGYTFTDYNMDWVKQSHGKSLEWIGDIDPNSGGSIYNQKFKGKATLTV
  	DKSSRTVYMELRSLTSEDTAVYYCARWRSSMDYWGQGTSVTVSS (SEQ ID NO: 1980)
  VH	EVQLQESGPELVKPGASVKITCKASGYTFTDYNMDWVKQSHGKSLEWIGDIDPNNGGTIYNQKFKGKATLTV
  	DKSSNTAYMELRSLASEDTAVYYCARWRSSMDYWGQGTSVSVSS (SEQ ID NO: 1981)
  VH	EVQLQESGPELVKPGASVKIPCKASGYTFTDYNMDWVKQSHGKSLEWIGDIDPNNGGTIYNQNFKGKATLTV
  	DKSSSTAYMELRSLTSEDTAVYYCARWRSSMDYWGQGTSVTVSS (SEQ ID NO: 1982)
  VH	EVQLQESGPELVKPGASVKIPCKASGYTFTDYNMDWVKQSHGKSLEWIGDIDPNNGGIIYNQKFKGKAALTV
  	DKSSSTAYMELRSLTSEDTAVYYCARWRSSMDYWGQGTSVTVSS (SEQ ID NO: 1983)
  VH	EVQLQESGPELVKPGASVKIPCKASGYTFTDYNMDWVKQSHGKSLEWIGDIDPNNGGIIYNQKFKGKAALTV
  	DKSSSTAYMELRSLTSEDTAVYYCTRWRSSMDYWGQGTSVTVSS (SEQ ID NO: 1984)
  VH	EVQLQESGPELVKPGASVKIPCKASGYTFTDYNMDWVKQSHGKSLEWIGDIDPNNGNTIYNQKFKGKATLTV
  	DKSSSTAYMELRSLTSEDTAVYYCTKWRSSMDYWGQGTSVTVSS (SEQ ID NO: 1985)
  VH	EVQLQESGPELVRPGASVKIPCKASGYTFTDYNMDWVMQSHGKSLEWIGDIDPNNGGTIYNQKFKGKATLTV
  	DKSSSTAYMELRSLTSEDTAVYYCTRWRSSMDYWGQGTSVTVSS (SEQ ID NO: 1986)
  VH	EVQLQESGPELVKPGASVKIPCKASGYTFTDYNVDWVKQSHGKSLEWIGDIDPNNGGTFYNQKFKGKATLTV
  	DKSSSTAHMELRSLTSEDTAVYYCVRWRSSMDYWGQGTSVTVSS (SEQ ID NO: 1987)
  VH	EVQLQESGPELVKPGASVKIPCKASGYTFTDYNMDWVKQSHGKSLEWIGDIDPNTGTTFYNQDFKGKATLTV
  	DKSSSTAYMELRSLTSEDTAVYYCARWRSSMDYWGQGTSLTVSS (SEQ ID NO: 1988)
  VH	EVQLQESGAELVRPGASVTLSCKASGYTFTDYEMHWVKQTPVHGLEWIGVIDPGTGGTAYNQKFKVKALLTA
  	DKSSNTAYMELRSLTSEDSAVYYCTSEKFGSNYYFDYWGQGTTLTVSS (SEQ ID NO: 1989)
  VH	EVQLQESGAELVRPGASVTLSCKASGYTFTDYEIHWVKQTPVHGLEWIGAIDPETGGTAYNQKFKGKAILTA
  	DKSSSTAYMELRSLTSEDSAVYYCTSEKFGSSYYFDYWGQGTTFTVSS (SEQ ID NO: 1990)
  VH	EVQLQESGPGLVKPSQSLSLTCTVTGYSITSDYAWNWIRQFPGNKLEWMGYITYSGSPTYNPSLKSQFSITR
  	DTSKNQFFLQLNSLTTEDTATYYCARGLGGHYFDYWGQGTTLTVSS (SEQ ID NO: 1991)
  VH	EVQLQESGPGLVKPSQSLSLTCTVTGYSITSDYAWNWIRQFPGNKLEWMGYITYSGSPTYNPSLKSQFSITR
  	DTSKNQFFLQLNSVTTEDTATYYCARGLGGHYFDYWGQGTTLTVSS (SEQ ID NO: 1992)
  VH	EVQLQESGPDLVKPSQSLSLTCTVTGYSITSGYSWHWIRQFPGNKLEWMGFIHYSGDTNYNPSLKSRFSITR
  	DTSKNQFFLHLNSVTPEDTATYYCASPSRLLFDYWGHGTTLTVSS (SEQ ID NO: 1993)
  VH	EVQLQESGPGLVAPSQSLSITCTVSGFSLTNYGVDWVRQSPGKGLEWLGVIWGVGSTNYNSALKSRLSISKD
  	NSKSQVFLKMNSLQTDDTAMYYCASDGFVYWGQGTLVTVSS (SEQ ID NO: 1994)
  VH	EVQLQESGPGLVAPSQSLSITCTVSGFSLTSYGVDWVRQSPGKGLEWLGVIWGIGSTNYNSALKSRLSISKD
  	NSKSQVFLKMNSLQSDDTAMYYCASDGFVYWGQGTLVTVSS (SEQ ID NO: 1995)
  VH	EVQLQESGPSLVQPSQSLSITCTVSGFSLTSYGVHWVRQSPGKGLEWLGVIWRGGNTDYNAAFMSRLSITKD
  	NSKSQVFFKMNSLQADDTAIYYCAASMIGGYWGQGTTLTVSS (SEQ ID NO: 1996)
  VH	EVQLQESGPSLVQPSQSLSITCTVSGFSLTNYGVHWVRQSPGKGLEWLGVIWRGGNTDYNAAFMSRLSITKD
  	NSKSQVFFKFHSLQTDDTAIYYCAASMIGGYWGQGTTLTVSS (SEQ ID NO: 1997)
  VH	QVQLVQSGAEVKKPGASVKVSCKASGYTFTSYWMHWVRQAPGQGLEWMGMIDPSNSETSLNQKFQGRVTMTV
  	DKSTNTVYMELSSLRSEDTAVYYCARSRGNYAYEMDYWGQGTLVTVSS (SEQ ID NO: 1998)
  VH	EVQLVQSGAEVKKPGASVKVSCKASGYTFTSYWMHWVRQAPGQGLEWMGMIDPSNSETSLNQKFQGRVTLNV
  	DKSTNTAYMELSSLRSEDTAVYYCARSRGNYAYEMDYWGQGTLVTVSS (SEQ ID NO: 1999)
  VH	EVQLVQSGTEVTKPGASVKVSCKASGYTFTSYWMHWVRQAPGQGLEWLGMIDPSNSETTLNQKFQGRVTMTV
  	DKSTNTVYMELTSLRSEDTAVYYCARSRGNYAYEMDYWGQGTLVTVSS (SEQ ID NO: 2000)
  VH	EVQLVQSGAEVKKPGASVKVSCKASGYTFTDYEMHWVRQAPGQGLEWMGIIDPGTGGTAYNQKFQGRVTMTA
  	DKSTSTVYMELSSLRSEDTAVYYCTSEKFGSNYYFDYWGQGTLVTVSS (SEQ ID NO: 2001)
  VH	EVQLVQSGAEVKKPGASVKVSCKASGYTFTDYEMHWVRQAPGQGLEWMGIIDPGTGGTAYNQKFQGRVTMTA
  	DKSTNTVYMELSSLRSEDTAVYYCTSEKFGSNYYFDYWGQGTLVTVSS (SEQ ID NO: 2002)
  VH	EVQLVQSGAEVKKPGASVKVSCKASGYTFTDYEMHWVRQAPGQRLEWMGVIDPGTGGTAYNQKFQGRVTITA
  	DKSASTAYMELSSLRSEDTAVYYCTSEKFGSNYYFDYWGQGTLVTVSS (SEQ ID NO: 2003)
  VL	DIVLTQTPAIMSASPGEKVTLTCSASSSVSSNYLYWYQQRPGSSPKLWIYSTSNLASGVPARFSGSGSGTSY
  	SLTISSMEAEDAASYFCHQWSSYPPTFGSGTKLEIK (SEQ ID NO: 2004)
  VL	DIVITQTTAIMSASPGEKVTLTCSASSSVSSNYLYWYQQRPGSSPKLWIYSTSNLASGVPARFSGSGSGTSY
  	SLTISSMEAEDAASYFCHQWSSYPPTFGSGTKLEIK (SEQ ID NO: 2005)
  VL	DIVMTQTPATMSASPGEKVTLTCSASSSVNSNYLYWYQQKPGSSPKVWIYSTSNLASGVPARFSGSGSGTSY
  	SLTISSMEAEDAASYFCHQWSSYPPTFGSGTKLELK (SEQ ID NO: 2006)
  VL	DIVMTQTTATMSASPGEKVTLTCSASSSVNSNYLYWYQQKPGSSPKVWIYSTSNLASGVPARFSGSGSGTSY
  	SLTISSMEAEDAASYFCHQWSSYPPTFGSGTKLELK (SEQ ID NO: 2007)
  VL	DIVLTQSTAIMSASPGEKVTLTCSASSGVNSNYLYWYQQKPGSSPKLWIYSTSNLASGVPARFSGSGSGTSY
  	SLTISSVEAEDAASYFCHQWSSYPPTFGSGTKLEIK (SEQ ID NO: 2008)
  VL	DIVLTQTPSSLSASLGDRVTISCSASQGISNYLNWYQQKPDGTVKLLIYYTSSLHSGVPSRFSGSGSGTDYS
  	LTISNLEPEDIATYYCQQYSKLPWTFGGGTKLEIK (SEQ ID NO: 2009)
  VL	DIVLTQSPSSLSASLGDRVTISCSASQGISNYLNWYQQKPDGTVKLLIYYTSSLHSGVPSRFSGSGSGTDYS
  	LTISNLEPEDIATYYCQQYSKLPWTFGGGTKLEIK (SEQ ID NO: 2010)
  VL	DIVITQSPSSLSASLGDRVTISCSASQGISNYLNWYQQKPDGTVKLLIYYTSSLHSGVPSRFSGSGSGTDYS
  	LTISNLEPEDIATYYCQQYSELPWTFGGGTKLEIK (SEQ ID NO: 2011)
  VL	DIVMTQSPSSLSASLGDRVTISCSASQGISNYLNWYQQRPDGTVKLLIYYTSSLHSGVPSRFSGSGSGTDYS
  	LTISNLEPEDIATYYCQQYSNLPWTFGGGTKLEIK (SEQ ID NO: 2012)
  VL	DIVMTQSPSSLSASLGDRVTISCSASQGISNYLNWYQQKPDGTVKLLIYYTSSLHSGVPSRFSGSGSGTDYS
  	LTISNLEPEDIATYYCQQYSELPWTFGGGTKLEIK (SEQ ID NO: 2013)
  VL	DIVMTQSTSSLSASLGDRVTISCSASQGISHYLNWYQQKPDGTVKLLIYYTSSLHSGVPSRFSGSGSGTDYS
  	LTIRNLEPEDIATYYCQQYSELPWTFGGGTKLEIK (SEQ ID NO: 2014)
  VL	DIVMTQSPSSLSASLGDRVTISCSASQGISHYLNWYQQKPDGTVKLLIYYTSSLHSGVPSRFSGSGSGTDYS
  	LTIRNLEPEDIATYYCQQYSELPWTFGGGTKLEIK (SEQ ID NO: 2015)
  VL	DIVMTQSPSSLSASLGDRVTISCSASQDISSYLNWYQQKPDGTVKLLIYYTSSLHSGVPSRFSGSGSGTDYS
  	LTISNLEPEDIATYYCQQYSELPWTFGGGTKLEIK (SEQ ID NO: 2016)
  VL	DIVMTQTPSSLSASLGDRVTISCSASQGISYYLNWYQQKPDGTIKLLIYYTLSLHSGVPSRFSGSGSGTDYS
  	LTISNLEPEDIATYYCQQYSELPWTFGGGTKLEIK (SEQ ID NO: 2017)
  VL	DIVMTQTPSSMSASLGDRVTISCSASQGISNYLNWYQQKPDGTVKLLIYYTSSLHSGVPSRFSGSGSGTDYS
  	LTISNLEPEDIATYYCQQYSYLPWTFGGGTKLEIK (SEQ ID NO: 2018)
  VL	DIVMTQTPSSLSASLGDRVTISCSASQGIGNYLNWYQQKPDGTVKLLIYYTSNLHSGVPSRFSGRGSGTDYS
  	LTISNLEPEDIATYYCQQYSNLPWTFGGGTKLEIK (SEQ ID NO: 2019)
  VL	DIVMTQSPSSLSASLGDRVTISCSASQGISNYLNWYQQKPDGTVKLLIYYTSNLHSGVPSRFSGSGSGTDYS
  	LTISDLAPEDIATYYCQQYSYLPWTFGGGTKLEIK (SEQ ID NO: 2020)
  VL	DIVITQSPLSLPVGLGDQASISCRSSQSLVHSNGNTYLHWYLQKPGQSPKLLIYKVSNRFSGVPDRFSGSGS
  	GTDFTLKISRVEAEDLGVYFCSQSTHVPYTFGGGTKLEIK (SEQ ID NO: 2021)
  VL	DIVLTQTPLSLPVSLGDQASISCRSSQSIVHSNGNTYLEWYLQKPGQSPKLLIYKVSNRFSGVPDRFSGSGS
  	GTNFTLKISRVEAEDLGVYYCFQGSHVPLTFGAGTKLELK (SEQ ID NO: 2022)
  VL	DIVLTQSPLSLPVSLGDQASISCRSSQSIVHSDGNTYLEWYLQKPGQSPKLLIYKVSNRFSGVPDRFSGSGS
  	GTDFTLKISRVEAEDLGIYYCFQGSHVPLTFGAGTKLELK (SEQ ID NO: 2023)
  VL	DIVITQTPLSLPVSLGDQASISCRSSQTIVHSDGNTYLEWYLQKPGQSPKLLIYKVSNRFSGVPDRFSGSGS
  	GTDFTLKISRVEAEDLGVYYCFQGSHVPLTFGAGTKLEIK (SEQ ID NO: 2024)
  VL	DIVMTQSTLSLPVSLGDQVSISCRSSQSIVHSDGNTYLEWYLQKPGQSPNLLIYKVSNRFSGVPDRFSGSGS
  	GTDFTLKISRVEAEDLGVYYCFQGSHVPLTFGAGTKLELK (SEQ ID NO: 2025)
  VL	DIVLTQDELSNPVTSGESVSISCRSSKSLLYKDGKTYLNWFLQRPGQSPQVLIYFMSTRASGVSDRFSGSGS
  	GTDFTLEISRVKAEDVGVYYCQQLVDFPFTFGSGTKLELK (SEQ ID NO: 2026)
  VL	DIVMTQDELYNPVTSGESVSISCRSSKSLLYKDGKTYLNWFLQRPGQSPQVLIYFMSTRASGVSDRFSGSGS
  	GTDFTLEISRVKAEDVGVYYCQQLVDFPFTFGSGTKLEIK (SEQ ID NO: 2027)
  VL	DIVMTQSPSSLTVTAGEKVTMSCKSSQSLLNSGTQKNYLTWYQQKPGQPPKLLIYWASTRESGVPDRFTGSG
  	SGTDFTLTISSVQAEDLAVYYCQNDYSYPLTFGAGTKLEIK (SEQ ID NO: 2028)
  VL	DIVLTQTTATLSVTPGDRVSLSCRASQSISDYLHWYQQKSHESPRLLIKYASQSISGIPSRFSGSGSGSDFT
  	LTVNSVEPEDVGVYYCQNGHSYPYTFGGGTKLEIK (SEQ ID NO: 2029)
  VL	DIVLTQSPDTLSVTPGDRVSLSCRASQSISDYLHWYQQKSHESPRLLIKYASQSISGIPSRFSGSGSGSDFT
  	LSINSVEPEDVGVYYCQNGHSYPYTFGGGTKLELK (SEQ ID NO: 2030)
  VL	EIVLTQSPATLSLSPGERATLSCRASSSVSSNYLYWYQQKPGQAPRLLIYSTSNRATGIPARFSGSGSGTDY
  	TLTISSLEPEDFAVYYCHQWSSYPPTFGQGTKLEIK (SEQ ID NO: 2031)
  VL	DIVLTQSPATLSLSPGERATLSCRASSSVSSNYLYWYQQKPGQAPRLLIYSTSNLATGIPARFSGSGSGTDY
  	TLTISSLEPEDFAVYFCHQWSSYPPTFGQGTKLEIK (SEQ ID NO: 2032)
  VL	DIVLTQSPGTLSLSPGEKVTLSCRASSSVSSNYLYWYQQKPGQAPRLVIYSTSNLATGIPDRFSGSGSGTDY
  	TLTISRLEPEDFAVYFCHQWSSYPPTFGQGTKVEIK (SEQ ID NO: 2034)
  VL	DVVMTQSPLSLPVTLGQPASISCRSSQTIVHSDGNTYLEWYQQRPGQSPRLLIYKVSNRFSGVPDRFSGSGS
  	GTDFTLKISRVEAEDVGVYYCFQGSHVPLTFGQGTKLEIK (SEQ ID NO: 2035)
  VL	DIVMTQSPLSLPVTLGQPASISCRSSQTIVHSDGNTYLEWYQQRPGQSPKLLIYKVSNRFSGVPDRFSGSGS
  	GTDFTLKISRVEAEDVGVYYCFQGSHVPLTFGQGTKLEIK (SEQ ID NO: 2036)
  VL	DIVMTQTPLSSPVTLGQPASISCRSSQTIVHSDGNTYLEWYQQRPGQPPRLLIYKVSNRFSGVPDRFSGSGA
  	GTDFTLKISRVEAEDVGVYYCFQGSHVPLTFGQGTKLEIK (SEQ ID NO: 2037)

• In some embodiments, the activatable anti-PD-1 antibody includes a CDR sequence shown in Table 8, a combination of VL CDR sequences (VL CDR1, VL CDR2, VL CDR3) selected from the group consisting of those combinations shown in a single row Table 8, a combination of VH CDR sequences (VH CDR1, VH CDR2, VH CDR3) selected from the group consisting of those combinations shown in Table 8, or a combination of VL CDR and VH CDR sequences (VL CDR1, VL CDR2, VL CDR3, VH CDR1, VH CDR2, VH CDR3) selected the group consisting of those combinations shown in Table 8. The CDR regions were defined according to AbM definition as described in the CDR definition table in Andrew C. R. Martin's Bioinformatics Group website at UCL.

• TABLE 8
  CDR Sequences for Antibodies and Activatable Antibodies that Bind PD-1

  VH

  VL

  	CDR1	CDR2			CDR2	CDR3
  AB	(SEQ ID	(SEQ ID	CDR3 (SEQ	CDR1 (SEQ ID	(SEQ ID	(SEQ ID
  Name	NO)	NO)	ID NO)	NO)	NO)	NO)
  M13	GFTFSGYAMS	YISNSGGNAH	EDYGTSPFVY	RASESVDNYGIS	AASNQGS	QQSKDVPWT
  	(653)	(658)	(664)	FMN (669)	(678)	(683)
  M19	GYTFTDYYMD	YIYPKNGGSS	KVVATDY	KSSQSLLYSSNQ	WASIRES	QQCDSYPWT
  	(654)	(659)	(665)	KNYL (670)	(679)	(684)
  M3	GFTFSNYAMS	YISNGGGDTH	ENYGTSPFVY	RASESVDNYGIS	AASNQGS	QQSKDVPWT
  	(655)	(660)	(666)	FMN (669)	(678)	(683)
  M5	GFSFSSYDMS	TISGGGRYTY	NYYGFDY	KASQDVGTAVA	WASTRHT	QQYSSYPWT
  	(656)	(661)	(667)	(671)	(680)	(685)
  M14	GFTFSSYGMS	TISGGGRDIY	LYLGFDY	LASQTIGTWLA	AATSLAD	QQLYSIPWT
  	(657)	(662)	(668)	(672)	(681)	(686)
  A	GFTFSGYAMS	YISNSGGNAH	EDYGTSPFVY
  	(653)	(658)	(664)
  Ab	GFTFSGYAMS	YISNSGGNAH	EDYGTSPFVY
  	(653)	(658)	(664)
  Ae	GFTFSGYAMS	YISNSGGNTH	EDYGTSPFVY
  	(653)	(663)	(664)
  Af	GFTFSGYAMS	YISNSGGNTH	EDYGTSPFVY
  	(653)	(663)	(664)
  Ba	GYTFTDYYMD	YIYPKNGGSS	KVVATDY
  	(654)	(659)	(665)
  Bb	GYTFTDYYMD	YIYPKNGGSS	KVVATDY
  	(654)	(659)	(665)
  C	GFTFSNYAMS	YISNGGGDTH	ENYGTSPFVY
  	(655)	(660)	(666)
  Ca	GFTFSNYAMS	AYISNQGGDT	ENYGTSPFVY
  	(655)	H (2041)	(666)
  D	GFSFSSYDMS	TISGGGRYTY	NYYGFDY
  	(656)	(661)	(667)
  1.0				RASESVDNYGIS	AASNQGS	QQSKDVPWT
  				FMN (673)	(678)	(683)
  1.1				RASESVDNYGIS	AASNQGS	QQSKDVPWT
  				FMN (673)	(678)	(683)
  1.2				RASESVDQYGIS	AASNQGS	QQSKDVPWT
  				FMN (674)	(678)	(683)
  1.4				RASESVDSYGIS	AASNQGS	QQSKDVPWT
  				FMN (675)	(678)	(683)
  1.5				RASESVDAYGIS	AASNQGS	QQSKDVPWT
  				FMN (676)	(678)	(683)
  1.6				RASESVDNYGIS	AASDQGS	QQSKDVPWT
  				FMN (673)	(682)	(683)
  cl				RASESVDAYGIS	AASNQGS	QQSKDVPWT
  1.7				FMN (676)	(678)	(683)
  1.9				RASESVDAY	AASNQGS	QQSKDVPWT
  				(676)GISFMN	(678)	(683)
  1.10				RASESVDAYGIS	AASNQGS	QQSKDVPWT
  				FMN (676)	(678)	(683)
  2				KSSQSLLYSSNQ	WASIRES	QQSDSYPWT
  				KNYLA (677)	(679)	(687)
  4				KASQDVGTAVA	WASTRHT	QQYSSYPWT
  				(671)	(680)	(685)

• In some embodiments, the activatable anti-PD-1 antibody comprises or is derived from an antibody that is manufactured, secreted or otherwise produced by a hybridoma, such as, for example, the hybridoma(s) disclosed in U.S. Pat. No. 8,927,697 and US Patent Application Publication Nos. US 2011-0171215 and US 2015-0152180, and deposited at the European Collection of Cell Cultures (ECACC) under Accession Number 08090902; 08090903; and Ser. No. 08/090,901.
• In some embodiments, the activatable anti-PD-1 antibody comprises or is derived from an antibody that is manufactured, secreted or otherwise produced by a hybridoma, such as, for example, the hybridoma(s) disclosed in US Patent Application Publication No. US 2014-0335093, and deposited at the Collection Nationale De Cultures De Microorganismes (CNCM) under deposit number 1-4122.
• In some embodiments, the activatable anti-PD-1 antibody comprises or is derived from an antibody that is manufactured, secreted or otherwise produced by a hybridoma, such as, for example, the hybridoma(s) disclosed in PCT Publication Nos. WO 2015/058573 or WO 2014/206107, and deposited at the China Culture Collection Committee General Microbiology Center under Accession no. 8351.
• In some embodiments, the activatable anti-PD-1 antibody comprises or is derived from an antibody that is manufactured, secreted or otherwise produced by a hybridoma, such as, for example, the hybridoma(s) disclosed in US Patent Application Publication No. US2011177088, and deposited at the Collection Nationale De Cultures De Microorganismes (CNCM) under deposit number 1-3745.
• In some embodiments, the activatable anti-PD-1 antibody includes a CDR sequence shown in Table 9, a combination of VL CDR sequences selected from the group consisting of those combinations shown in Table 9, and/or a combination of VH CDR sequences selected from the group consisting of those combinations shown in Table 9.
• In some embodiments, the activatable anti-PD-1 antibody includes a combination of heavy chain CDR sequences selected from the group consisting of the combinations shown in Group A in Table 9. In some embodiments, the activatable anti-PD-1 antibody includes a combination of light chain CDR sequences selected from the group consisting of the combinations shown in Group A in Table 9. In some embodiments, the activatable anti-PD-1 antibody includes a combination of heavy chain CDR sequences selected from the group consisting of the combinations shown in Group A in Table 9, and a combination of light chain CDR sequences selected from the group consisting of the combinations shown in Group A in Table 9.
• In some embodiments, the activatable anti-PD-1 antibody includes a combination of heavy chain CDR sequences selected from the group consisting of the combinations shown in Group B in Table 9. In some embodiments, the activatable anti-PD-1 antibody includes a combination of light chain CDR sequences selected from the group consisting of the combinations shown in Group B in Table 9. In some embodiments, the activatable anti-PD-1 antibody includes a combination of heavy chain CDR sequences selected from the group consisting of the combinations shown in Group B in Table 9, and a combination of light chain CDR sequences selected from the group consisting of the combinations shown in Group B in Table 9.
• In some embodiments, the activatable anti-PD-1 antibody includes a combination of heavy chain CDR sequences selected from the group consisting of the combinations shown in Group C in Table 9. In some embodiments, the activatable anti-PD-1 antibody includes a combination of light chain CDR sequences selected from the group consisting of the combinations shown in Group C in Table 9. In some embodiments, the activatable anti-PD-1 antibody includes a combination of heavy chain CDR sequences selected from the group consisting of the combinations shown in Group C in Table 9, and a combination of light chain CDR sequences selected from the group consisting of the combinations shown in Group C in Table 9.
• In some embodiments, the activatable anti-PD-1 antibody includes a combination of heavy chain CDR sequences selected from the group consisting of the combinations shown in Group E in Table 9. In some embodiments, the activatable anti-PD-1 antibody includes a combination of light chain CDR sequences selected from the group consisting of the combinations shown in Group E in Table 9. In some embodiments, the activatable anti-PD-1 antibody includes a combination of heavy chain CDR sequences selected from the group consisting of the combinations shown in Group E in Table 9, and a combination of light chain CDR sequences selected from the group consisting of the combinations shown in Group E in Table 9.
• In some embodiments, the activatable anti-PD-1 antibody includes a combination of heavy chain CDR sequences selected from the group consisting of the combinations shown in Group F in Table 9. In some embodiments, the activatable anti-PD-1 antibody includes a combination of light chain CDR sequences selected from the group consisting of the combinations shown in Group F in Table 9. In some embodiments, the activatable anti-PD-1 antibody includes a combination of heavy chain CDR sequences selected from the group consisting of the combinations shown in Group F in Table 9, and a combination of light chain CDR sequences selected from the group consisting of the combinations shown in Group F in Table 9.
• In some embodiments, the activatable anti-PD-1 antibody includes a combination of heavy chain CDR sequences selected from the group consisting of the combinations shown in Group G in Table 9. In some embodiments, the activatable anti-PD-1 antibody includes a combination of light chain CDR sequences selected from the group consisting of the combinations shown in Group Gin Table 9. In some embodiments, the activatable anti-PD-1 antibody includes a combination of heavy chain CDR sequences selected from the group consisting of the combinations shown in Group Gin Table 9, and a combination of light chain CDR sequences selected from the group consisting of the combinations shown in Group G in Table 9.
• In some embodiments, the activatable anti-PD-1 antibody includes a combination of heavy chain CDR sequences selected from the group consisting of the combinations shown in Group H in Table 9. In some embodiments, the activatable anti-PD-1 antibody includes a combination of light chain CDR sequences selected from the group consisting of the combinations shown in Group H in Table 9. In some embodiments, the activatable anti-PD-1 antibody includes a combination of heavy chain CDR sequences selected from the group consisting of the combinations shown in Group H in Table 9, and a combination of light chain CDR sequences selected from the group consisting of the combinations shown in Group H in Table 9.
• In some embodiments, the activatable anti-PD-1 antibody includes a combination of heavy chain CDR sequences selected from the group consisting of the combinations shown in Group L in Table 9. In some embodiments, the activatable anti-PD-1 antibody includes a combination of light chain CDR sequences selected from the group consisting of the combinations shown in Group L in Table 9. In some embodiments, the activatable anti-PD-1 antibody includes a combination of heavy chain CDR sequences selected from the group consisting of the combinations shown in Group L in Table 9, and a combination of light chain CDR sequences selected from the group consisting of the combinations shown in Group L in Table 9.
• In some embodiments, the activatable anti-PD-1 antibody includes a combination of heavy chain CDR sequences selected from the group consisting of the combinations shown in Group M in Table 9. In some embodiments, the activatable anti-PD-1 antibody includes a combination of light chain CDR sequences selected from the group consisting of the combinations shown in Group M in Table 9. In some embodiments, the activatable anti-PD-1 antibody includes a combination of heavy chain CDR sequences selected from the group consisting of the combinations shown in Group M in Table 9, and a combination of light chain CDR sequences selected from the group consisting of the combinations shown in Group M in Table 9.
• In some embodiments, the activatable anti-PD-1 antibody includes a combination of heavy chain CDR sequences selected from the group consisting of the combinations shown in Group N in Table 9. In some embodiments, the activatable anti-PD-1 antibody includes a combination of light chain CDR sequences selected from the group consisting of the combinations shown in Group N in Table 9. In some embodiments, the activatable anti-PD-1 antibody includes a combination of heavy chain CDR sequences selected from the group consisting of the combinations shown in Group N in Table 9, and a combination of light chain CDR sequences selected from the group consisting of the combinations shown in Group N in Table 9.
• In some embodiments, the activatable anti-PD-1 antibody includes a combination of heavy chain CDR sequences selected from the group consisting of the combinations shown in Group O in Table 9. In some embodiments, the activatable anti-PD-1 antibody includes a combination of light chain CDR sequences selected from the group consisting of the combinations shown in Group O in Table 9. In some embodiments, the activatable anti-PD-1 antibody includes a combination of heavy chain CDR sequences selected from the group consisting of the combinations shown in Group O in Table 9, and a combination of light chain CDR sequences selected from the group consisting of the combinations shown in Group O in Table 9.
• In some embodiments, the activatable anti-PD-1 antibody includes a combination of heavy chain CDR sequences selected from the group consisting of the combinations shown in Group P in Table 9. In some embodiments, the activatable anti-PD-1 antibody includes a combination of light chain CDR sequences selected from the group consisting of the combinations shown in Group P in Table 9. In some embodiments, the activatable anti-PD-1 antibody includes a combination of heavy chain CDR sequences selected from the group consisting of the combinations shown in Group P in Table 9, and a combination of light chain CDR sequences selected from the group consisting of the combinations shown in Group P in Table 9.
• In some embodiments, the activatable anti-PD-1 antibody includes a combination of heavy chain CDR sequences selected from the group consisting of the combinations shown in Group Q in Table 9. In some embodiments, the activatable anti-PD-1 antibody includes a combination of light chain CDR sequences selected from the group consisting of the combinations shown in Group Q in Table 9. In some embodiments, the activatable anti-PD-1 antibody includes a combination of heavy chain CDR sequences selected from the group consisting of the combinations shown in Group Q in Table 9, and a combination of light chain CDR sequences selected from the group consisting of the combinations shown in Group Q in Table 9.
• In some embodiments, the activatable anti-PD-1 antibody includes a combination of heavy chain CDR sequences selected from the group consisting of the combinations shown in Group R in Table 9. In some embodiments, the activatable anti-PD-1 antibody includes a combination of light chain CDR sequences selected from the group consisting of the combinations shown in Group R in Table 9. In some embodiments, the activatable anti-PD-1 antibody includes a combination of heavy chain CDR sequences selected from the group consisting of the combinations shown in Group R in Table 9, and a combination of light chain CDR sequences selected from the group consisting of the combinations shown in Group R in Table 9.
• In some embodiments, the activatable anti-PD-1 antibody includes a combination of heavy chain CDR sequences selected from the group consisting of the combinations shown in Group T in Table 9. In some embodiments, the activatable anti-PD-1 antibody includes a combination of light chain CDR sequences selected from the group consisting of the combinations shown in Group T in Table 9. In some embodiments, the activatable anti-PD-1 antibody includes a combination of heavy chain CDR sequences selected from the group consisting of the combinations shown in Group T in Table 9, and a combination of light chain CDR sequences selected from the group consisting of the combinations shown in Group T in Table 9.
• In some embodiments, the activatable anti-PD-1 antibody includes a combination of heavy chain CDR sequences selected from the group consisting of the combinations shown in Group U in Table 9. In some embodiments, the activatable anti-PD-1 antibody includes a combination of light chain CDR sequences selected from the group consisting of the combinations shown in Group U in Table 9. In some embodiments, the activatable anti-PD-1 antibody includes a combination of heavy chain CDR sequences selected from the group consisting of the combinations shown in Group U in Table 9, and a combination of light chain CDR sequences selected from the group consisting of the combinations shown in Group U in Table 9.
• In some embodiments, the activatable anti-PD-1 antibody includes a combination of heavy chain CDR sequences selected from the group consisting of the combinations shown in Group V in Table 9. In some embodiments, the activatable anti-PD-1 antibody includes a combination of light chain CDR sequences selected from the group consisting of the combinations shown in Group V in Table 9. In some embodiments, the activatable anti-PD-1 antibody includes a combination of heavy chain CDR sequences selected from the group consisting of the combinations shown in Group V in Table 9, and a combination of light chain CDR sequences selected from the group consisting of the combinations shown in Group V in Table 9.
• In some embodiments, the activatable anti-PD-1 antibody includes a combination of heavy chain CDR sequences selected from the group consisting of the combinations shown in Group W in Table 9. In some embodiments, the activatable anti-PD-1 antibody includes a combination of light chain CDR sequences selected from the group consisting of the combinations shown in Group W in Table 9. In some embodiments, the activatable anti-PD-1 antibody includes a combination of heavy chain CDR sequences selected from the group consisting of the combinations shown in Group W in Table 9, and a combination of light chain CDR sequences selected from the group consisting of the combinations shown in Group W in Table 9.
• In some embodiments, the activatable anti-PD-1 antibody includes a combination of heavy chain CDR sequences selected from the group consisting of the combinations shown in Group X in Table 9. In some embodiments, the activatable anti-PD-1 antibody includes a combination of light chain CDR sequences selected from the group consisting of the combinations shown in Group X in Table 9. In some embodiments, the activatable anti-PD-1 antibody includes a combination of heavy chain CDR sequences selected from the group consisting of the combinations shown in Group X in Table 9, and a combination of light chain CDR sequences selected from the group consisting of the combinations shown in Group X in Table 9.

• TABLE 9
  Additional CDR Sequences for Antibodies and Activatable Antibodies that Bind PD-1

  VH

  VL

  CDR1	CDR2	CDR3	CDR1	CDR2	CDR3
  (SEQ ID NO:)	(SEQ ID NO:)	(SEQ ID NO:)	(SEQ ID NO:)	(SEQ ID NO:)	(SEQ ID NO:)

  Group A

  NYGMH	VIWYDGSNKYYADSVKG	NDDY (700)	RASQSVSSYLA	DASNRAT	QQRSNWPLT
  (688)	(694)		(704)	(706)	(710)
  NYGFH	VIWYDGSKKYYADSVKG	GDDY (701)	RASQSVSSYLA	DTSNRAT	QQRSNWPLT
  (689)	(695)		(704)	(707)	(710)
  NYGMH	LIWYDGSNKYYADSVKG	NVDH (702)	RASQSVSSYLA	DASNRAT	QQSSNWPRT
  (688)	(696)		(704)	(706)	(711)
  NSGMH	VIWYDGSKRYYADSVKG	NDDY (700)	RASQSVSSYLA	DASNRAT	QQSSNWPRT
  (690)	(697)		(704)	(706)	(711)
  RSSFFWG	SIYYSGSTYYNPSLKS	DYDILTGDEDY	RASQGISSWLA	AASNLRS	QQYYSYPRT
  (691)	(698)	(703)	(705)	(708)	(712)
  SYGFH	VIWYDGSKKYYADSVKG	GDDY (701)	RASQSVSSYLA	DASNRAT	QQRSNWPLT
  (692)	(695)		(704)	(706)	(710)
  RSSYFWG	SIFYSGETYFNPSLKS	DYDILTGDEDY	RASQGISSWLA	AASSLQS	QQYYSYPRT
  (693)	(699)	(703)	(705)	(709)	(712)

  Group B

  SYYLY	GVNPSNGGTNFSEKFK	RDSNYDGGFDY	RASKSVSTSGFSY	LASNLES	QHSWELPLT
  (713)	S (715)	(717)	LH (719)	(721)	(723)
  NYYMY	GINPSNGGTNFNEKFK	RDYRFDMGFDY	RASKGVSTSGYSY	LASYLES	QHSRDLPLT
  (714)	N (716)	(718)	LH (720)	(722)	(724)
  AASGFTFS	TITGGGRNTYYPDSVK	QGYDGYTWFAY	RASESVDNSGISF	AASNPGS	QQSKEVPWT
  SYAMS	G (817)	(823)	MN (830)	(836)	(840)
  (627)
  AASGFTFS	TISGGGSNTYYPDSVK	IYDVAWFAY	RSSQTIVHSDGNT	AASNQGS	FQGSHVPYT
  SFGMS	(818)	(824)	YLE (831)	(678)	(841)
  (811)
  KGSGYSFT	VISTHYGDTVYNQRFK	EGYGSLFYFDQ	RASESVDSYGNSF	KVSNRFS	QQNNEVPLT
  DYALH	G (1832)	(825)	MN (832)	(837)	(842)
  (812)
  KASGYAFT	YIDLYNGDTSYNEKF	EGRLSFDY	RSSQSIVQSNGNT	LASNLDS	FQGSHVPYT
  SYNIY	(819)	(826)	YLE (833)	(838)	(843)
  (813)
  AASGFTFS	YISGGGGNTYYPDTL	ISLTGIFDY	RSSQTIVHGNGNT	SASTLAS	QQGFGTSNVE
  NYDMS	(820)	(827)	YLE (834)	(839)	NP (844)
  (814)
  AASGFTFN	TISGGGSYTYYPDSVQ	GNYVYVMDY	QASENIYSSLA
  SYGMS	G (821)	(828)	(835)
  (815)
  KGSGYIFT	VISTYYSNINYNQKFK	EGFGRPYWYFD
  DYVMH	G (822)	V (829)
  (816)

  Group C

  GYSITSDY	YINYSGSTSYNPSLKS	WIGSSAWYFDV	RSGQNIVHSNGNTY	KVSNRFF	FQGSHVPFT
  AWN	(847)	(849)	LE (851)	(853)	(855)
  (845)
  GYTFTTYY	GINPSNGGINFNEKFK	RDYRYDRGFDY	RASKSVSTSGFNYI	LASNLES	QHSRELPLT
  LY (846)	(848)	(850)	H (852)	(721)	(856)

  Group E

  SYGIS	WISAYNGNTNYAQ	DADYSSGSGY	SGDALPKQYAY	KDTERPS	QSADNSITYR
  (857)	KLQG (861)	(865)	(869)	(872)	V (876)
  SYYIH	IINPRGATISYAQ	AGIYGFDFDY	TGTSNDVGGYNYVS	DVTNRPS	SSYTIVTNFE
  (858)	KFQG (862)	(866)	(870)	(873)	VL (877)
  SGAYYWS	YIYYNGNTYYNPS	ASDYVWGGYRYM	SGSNSNIGSNSVN	GNNQRPS	AAWDDSLNGP
  (859)	LRS (863)	DAFDI (867)	(871)	(874)	V (878)
  SSYWMS	AISGSGGSTYYAD	ENWGSYFDL	RASQGISSWLA	KASTLES	QQSYSTPWT
  (860)	SVKG (864)	(868)	(705)	(875)	(879)

  Group F

  SSWIH	YIYPSTGFTEYNQ	WRDSSGYHAMDY	RASQSVSTSGYSYMH	FGSNLES	QHSWEIPYT
  (880)	KFKD (881)	(882)	(883)	(884)	(885)

  Group L

  GFTFSSYD	VIWYSGSNTYYND	AYFGVDV	RASQGIGNTLA	RASQGIG	QQYDHVPLT
  YYMH	SLKS (887)	(888)	(889)	NTLA	(891)
  (886)				(889)

  Group G

  GFSLTSYG	VIWAGGSTNYNSA	GFSLTSYGVH	KASQSVSNDVA	YAFHRFT
  VH (892)	LMS (895)	(896)	(898)	(900)
  VIWAGGST	ARAYGNYWYIDV	ARAYGNYWYIDV	KSSESVSNDVA
  NYNPSLKS	(896)	(897)	(899)
  (893)
  VIYAGGST	HQAYSSPYT
  NYNPSLKS	(895)
  (894)

  Group H

  DYEMH	VIESETGGTAYNQ	EGITTVATTYYW	RSSQSIVHSNGNTYLE	KVSNRFS	FQGSHVPLT
  (901)	KFKG (902)	YFDV (903)	(904)	(905)	(906)

  Group M

  GYTFTTYP	NFHPYNDDTKYNE		RASSSVISSYLH	STSNLAS	QQYNGYPLT
  IE (907)	KFK (908)		(909)	(910)	(911)
  					QQYNSYPLT
  					(912)

  Group N

  SYYLY	GVNPSNGGTNFSE	RDSNYDGGFDY	RASKSVSTSGFSYLH	LASNLES	QHSWELPLT
  (713)	KFK (1596)	(717)	(719)	(721)	(723)

  Group P

  GYTFTTY	YPGTGG (1597)	WTTGTGAY	SQSLLDSGNQKNF	WAS	DYSYPY
  (854)		(1598)	(1599)	(1600)	(1601)
  TYWMH	NIYPGTGGSNFDE		KSSQSLLDSGNQKNFL	WASTRES	QNDYSYPYT
  (1602)	KFK (1603)		(1833)	(1604)	(1605)
  GYTFTTYW
  MH
  (1606)

  Group Q

  GFTFSSYT	ISDTGGNT	AKDQGGSYPYYF	QSISSY (1610)	AAS	QQSYSTPPIT
  (1607)	(1608)	HY (1609)		(1611)	(1612)
  GFTVSNNY	IYSGGFT	ARYYYDTSDYWT	QSVSSN (1616)	GAS	QQYNNWPLT
  (1613)	(1614)	FFDY (1615)		(1617)	(1618)
  GFTFSSYG	IWYDGSNI	ARPGHWNYFFEY	QSINNY (1622)	TAS	QQSYSTPPLT
  (1619)	(1620)	(1621)		(1623)	(1624)
  GFTFRNYD	IGSAGDT	TRDIHCSSTRCY	QSISNY (1628)	AAS	QQSYSTPPIT
  (1625)	(1626)	GMDV (1627)		(1611)	(1612)
  GFKFSNEW	IKSKTDGGTT	TTDQDFWSGYYT		AAS	QQSYSTPPIT
  (1629)	(1630)	GADYYGMDV		(1611)	(1612)
  		(1631)
  GGSLNGYY	IDHSGST	AREGLLPFDY	QSVYSNY (1635)	AAS	HQYATSPWT
  (1632)	(1633)	(1634)		(1611)	(1636)
  DDSISSTT	MSYNGNN	ARHLGYNGNWYP	QSVSSSY (1639)	GAS	QQYGSSPWT
  YY	(622)	FDF (1638)		(1640)	(1641)
  (1637)
  GFTFDDYA	INWSGNNI	TKDISITGTLDA	QGISNW (1645)	SAS	QQAHSFPLT
  (1642)	(1643)	FDV (1644)		(1646)	(1647)
  GFTFSSYG	IWSDGDSE	ARDRDLEDI	QGIRND (1650)	AAS	LQHNSYPLT
  (1619)	(1648)	(1649)		(1611)	(1651)
  GFTFSNFG	ISGGGRDT	VKWGNIYFDY	LSINTF (1655)	AAS	QQSSNTPFT
  (1652)	(1653)	(1654)		(1611)	(1656)
  GFTFDDYG	ISWNDGKT	ARDWQYLIERYF	QSVSSSY (1639)	GAS	QQYGSSPWT
  (1657)	(1658)	DY (1659)		(1640)	(1641)
  GFTFDDYG	IGWTGGRS	ARDRQWLVQWYF	QSISSY (1610)	AAS	QQSYSTPPIT
  (1657)	(1660)	DY (1661)		(1611)	(1612)
  GFTFDDYG	ISWNDGKT	ARDWQYLIDRYF
  (1657)	(1658)	DF (1662)
  GFTFDDYA	IGWSSGSI	AKAYTFMITLYF
  (1642)	(1663)	DY (1664)
  GFTFDDYD	SGWNRGSL	AKGFVVVSAAYF
  (1665)	(1666)	DY (1667)
  GVTFRNFA	IIPFFSAA	AREGERGHTYGF
  (1668)	(1669)	DY (1670)
  GFTFDDYA	INWNRGRT	AKAEQWLDEGYF
  (1642)	(1671)	DY (1672)
  GFTFEDYA	ISDSGGST	AKDQGGSYPYYF
  (1673)	(1674)	HY (1609)
  GYTFTSFY	IGWSNVKI	VKAYTSMLTLYF
  (1675)	(1676)	DY (1677)
  GGSISSYH	INPSDGST	ARRVAGDIFDI
  (1678)	(1679)	(1680)
  GFTFEDYG	IYYIGST	ARVPVGATGASD
  (1681)	(1682)	V (1683)
  GFTFSAYA	ISWTGGNT	TRDRQWLMQWYF
  (1684)	(1685)	DY (1686)
  GFALHDYA	ISYGGSDK	AKSAHWNFFFDY
  (1687)	(1688)	(1689)
  GDSISSTA	ISWNSGVI	AKGSGSYYVSWF
  YH	(1717)	DP (1718)
  (1687)
  GFTFSTYA	ITYNGNT	ARHLGYNSDFFP
  (1690)	(1691)	FDF (1692)
  	IGGSGDST	VKVRNYDGSFDI
  	(1693)	(1694)

  Group R

  SYGMS	TMSGGGRDIYYPD	QYYDDWFAY	RASQSISNNLH	YASQSIS	QQSNSWPLT
  (1751)	SMKG (1752)	(1753)	(1754)	(1755)	(1756)
  TYGVH	VIWSGGSTDYNAA	EKSVYGNYVGAM	KASQSVSDDVA	YAFNRYT	QQDYRSPWT
  (1757)	FIS (1758)	DY (1759)	(1760)	(1761)	(1762)
  SYGMS	TISGGGRDIYYPD	QYYDDWFAY	RASQSISNDLH	YVSQSIS	QQSDSWPLT
  (1751)	SVKG (1763)	(1753)	(1764)	(1765)	(1766)
  SDYAWN	YISYSGYTSYNPS	SLDYDYGTMDY	RANSSVSSMH	AISNLAF	QQWSSRPPT
  (1767)	LKS (1768)	(1769)	(1770)	(1771)	(1772)
  SYDMS	TISGGGSYTYYQD	PYGPYFDY	HASQSINVWLS	ASNLHT	QQGQSYPWT
  (1773)	SVKG (1774)	(1775)	(1776)	(1777)	(1778)
  SDYAWN	YISYSGYTSYNPS	SLDYDYGTMDY	RANSSVSSMH	AISNLAF	QQWNSRPPT
  (1767)	LKS (1768)	(1769)	(1770)	(1771)	(1779)
  YYDMS	TISGGGRNTYFID	PYEGAVDF	KASQDVDNAVA	WASTRHH	QQYSTFPYT
  (1780)	SVKG (1781)	(1782)	(1783)	(1784)	(1785)
  SYGMS	TISGGGRDTYYLD	QYYDDWFAY	RASQSLSNNLH	YASQSIS	QQSNSWPLT
  (1751)	SVKG (1786)	(1753)	(1787)	(1755)	(1756)
  NNWIG	DFYPGGGYTNYNE	GYGTNYWYFDV	KASQSVSNDVA	YAFTRYI	QQDYSSPYT
  (1788)	KFKG (1789)	(1790)	(1791)	(1792)	(1793)
  NFGMN	WISGYTREPTYAA	DVFDY (1796)	RASESVDNYGYSFMN	RASNLES	QQSNADPT
  (1794)	DFKG (1795)		(1797)	(1798)	(1799)

  Group T

  GYTFTSYY	GVNPSNGGTNFNE	RDYRYDMGFDY	RASKGVSTSGYSYLH	LASYLE	QHSRELPLT
  MY	KFKS (1801)	(1802)	(1803)	(1804)	(1805)
  (1800)
  GYTFTNYY	GINPSNGGTNYNE	RDYRYDMGFDY
  MY	KFKN (890)	(1802)
  (1806)

  Group U

  G	W (I/V) S A	(Q/—) GY	S G D A L		Q Q
  (T/R/I)	(Y/H) N G N T	(G/D)(N/V)Y	(P/T/S)		(N/S/W)
  (F/L)	(K/N) Y A Q K	(L/S)(Y/W)	(M/T/E/K) Q Y		(Y/K/I)
  (S/E/	L Q G (1882)	(D/A)(Y/V)	(G/A) Y (1884)		(N/E/S)
  T/P/R)		(1883)			(S/V/D/T)
  (T/S/					P (Y/W) T
  H/Q/R/					(1885)
  W)
  (F/Y/Q)
  (1881)
  (T/R/W/Q/	(T/A) I S G	D
  H/S)	(S/G) G	(A/V/S)(D/E) Y
  (Y/F/Q)	(S/G).(S/D/N)	(S/G/R)(S/L/
  G (M/I)	T Y Y (A/P/S)	T) (1888),
  (1886)	D S V (K/Q) G	with the
  	(1887)	proviso that
  		if A at
  		position 2,
  		then not D
  		or S in
  		position 5
  		GYALDY
  		(2038)
  GYIFSSY	FPGSGS (1890)	GYGNYLYFDV	KASQSVSDDVA	YAFKRYI	QQNYNSPYT
  (1889)		(1891)	(1760)	(1892)	(1893)
  SYWIG	KIFPGSGSADYNE	DSEYSSGSGY	SGDALTTQYAY	KDTERPS	QSADNSITYR
  (1894)	NFKG (1895)	(1896)	(1897)	(872)	V (876)
  		QRDSAWFAS	RASESVDNSGISFMS	ATSKLAS	QQWISDPWT
  		(2039)	(1898)	(1899)	(1900)
  			SGDALSEQYAY	TASNQGS	QQSKEVPWT
  			(1901)	(1902)	(840)
  			SGDALPKQYAY
  			(869)
  			SGDALPMQYGY
  			(1903)
  			RTSSSVNYMH
  			(1904)
  GYRFTWY	SAYNGN (1906)	DVDYSSGSGY
  (1905)		(1907)
  WYGIS	WISAYNGNTNYAQ	DAEYSLGSGY
  (1908)	KLQG (861)	(1909)
  GYRFSTF	SAHNGN (1911)	DAEYGSGSGY
  (1910)		(1912)
  TFGIS	WVSAHNGNTNYAQ	DADYGSGSGY
  (1913)	KLQG (1914)	(1915)
  GYRFETY	SYSGR (1917)	DVDYGTGSGY
  (1916)		(1918)
  GYRFRQY	YISYSGRTSYNPS	DVDYGSGSGY
  (1919)	LTS (1920)	(1921)
  QYGIS	SGGGSD (1923)	DAEYGSGSGY
  (1922)		(1912)
  GYRFTRY	TISGGGSDTYYPD	GYALDY
  (1924)	SVQG (1925)	(2038)
  RYGIS		QGYDVYSWFAY
  (1926)		(1927)
  GYRFPHY
  (1928)
  HYGIS
  (1929)
  GYRFTRQ
  (1930)
  RQGIS
  (1931)
  GHSITSDY
  (1932)
  SDYAWN
  (1767)
  GFTFSTF
  (1933)
  TFGMS
  (1934)

  Group V

  GWSLTGPG	IYGDGST	AYEYAMDW	WSVSTSGKSY	LLS	YHIRDLT
  (1935)	(1936)	(1937)	(1938)	(1939)	(2040)

  Group W

  GYTFTSYW	YPGSSL (1941)	LSTGTFAY	KSSQSLWDSTNQKNFL	WTSTRES	QNDYFYPLT
  IN		(1942)	T (1943)	(1944)	(1945)
  (1940)
  GYTFTSY	NIYPGSSLTNYNE	LTTGTFAY	KSSQSLWDSGNQKNFL	WTSYRES	QNDYFYPHT
  (1946)	KFKN (1947)	(1948)	T (1949)	(1950)	(1951)
  SYWIN	YPGSSI (1953)	LLTGTFAY	KSSQSLLDSGNQKNFL	WTS	QNDYSYPLT
  (1952)		(1954)	T (1955)	(T/Y)	(1957)
  				RES
  				(1956)
  	NIYPGSSITNYNE	L(L/S)TGTFAY	KSSQSL(W/L)DS(G/		QNDY(F/S)Y
  	KFKN (1958)	(1959)	T)NQKNFLT (1960)		P(L/H)T
  					(1961)
  	WPGSSL (1962)
  	NIWPGSSLTNYNE
  	KFKN (1963)
  	NIYPGSSSTNYNE
  	KFKN (1964)
  	NI(Y/W)PGSS
  	(L/I/S)TNYNEK
  	FKN (1965)

  Group X

  GLTFSSSG	IWYDGSKR	ATNNDY	RASQSVSSYLA	TASNRAT	QQYSNWPRT
  (1966)	(1706)	(1967)	(704)	(1968)	(1969)

• The ABs in the activatable antibodies of the disclosure specifically bind a PD-1 target, such as, for example, mammalian PD-1. In some embodiments, such Abs bind mammalian PD-1. In some embodiments, such Abs bind human PD-1. In some embodiments, such Abs bind non-human primate PD-1. Also included in the disclosure are ABs that bind to the same PD-1 epitope as an antibody of the disclosure and/or an activated activatable antibody described herein. Also included in the disclosure are ABs that compete with an anti-PD-1 antibody and/or an activated anti-PD-1 activatable antibody described herein for binding to a PD-1 target, e.g., human PD-1. Also included in the disclosure are ABs that cross-compete with an anti-PD-1 antibody and/or an activated anti-PD-1 activatable antibody described herein for binding to a PD-1 target, e.g., human PD-1.
• The activatable anti-PD-1 antibodies provided herein include a masking moiety. In some embodiments, the masking moiety is an amino acid sequence that is coupled or otherwise attached to the anti-PD-1 antibody and is positioned within the activatable anti-PD-1 antibody construct such that the masking moiety reduces the ability of the anti-PD-1 antibody to specifically bind PD-1. Suitable masking moieties are identified using any of a variety of known techniques. For example, peptide masking moieties are identified using the methods described in PCT Publication No. WO 2009/025846 by Daugherty et al., the contents of which are hereby incorporated by reference in their entirety.
• The activatable anti-PD-1 antibodies provided herein include a cleavable moiety. In some embodiments, the cleavable moiety includes an amino acid sequence that is a substrate for a protease, usually an extracellular protease. Suitable substrates are identified using any of a variety of known techniques. For example, peptide substrates are identified using the methods described in U.S. Pat. No. 7,666,817 by Daugherty et al.; in U.S. Pat. No. 8,563,269 by Stagliano et al.; and in PCT Publication No. WO 2014/026136 by La Porte et al., the contents of each of which are hereby incorporated by reference in their entirety. (See also Boulware et al. “Evolutionary optimization of peptide substrates for proteases that exhibit rapid hydrolysis kinetics.” Biotechnol Bioeng. 106.3 (2010): 339-46).
• Exemplary substrates include but are not limited to substrates cleavable by one or more of the following enzymes or proteases listed in Table 3.

• TABLE 3
  Exemplary Proteases and/or Enzymes

  ADAMS, ADAMTS,	Cysteine proteinases,	Serine proteases, e.g.,
  e.g. ADAM8	e.g., Cruzipain	activated protein C
  ADAM9	Legumain	Cathepsin A
  ADAM
  10	Otubain-2	Cathepsin G
  ADAM12	KLKs, e.g.,	Chymase
  ADAM15	KLK4	coagulation factor proteases
  ADAM17/TACE	KLK5	(e.g., FVIIa, FIXa, FXa,
  ADAMDEC1	KLK6	FXIa, FXIIa)
  ADAMTS1	KLK7	Elastase
  ADAMTS4	KLK8	Granzyme B
  ADAMTS5	KLK10	Guanidinobenzoatase
  Aspartate proteases,	KLK11	HtrA1
  e.g., BACE	KLK13	Human Neutrophil Elastase
  Renin	KLK14	Lactoferrin
  Aspartic cathepsins,	Metallo proteinases,	Marapsin
  e.g., Cathepsin D	e.g., Meprin	NS3/4A
  Cathepsin E	Neprilysin	PACE4
  Caspases, e.g.,	PSMA	Plasmin
  Caspase
  1	BMP-1	PSA
  Caspase
  2	MMPs, e.g.,	tPA
  Caspase
  3	MMP1	Thrombin
  Caspase
  4	MMP2	Tryptase
  Caspase
  5	MMP3	uPA
  Caspase
  6	MMP7	Type II Transmembrane
  Caspase 7	MMP8	Serine Proteases (TTSPs),
  Caspase 8	MMP9	e.g., DESC1
  Caspase
  9	MMP10	DPP-4
  Caspase 10	MMP11	FAP
  Caspase
  14	MMP12	Hepsin
  Cysteine cathepsins,	MMP13	Matriptase-2
  e.g., Cathepsin B	MMP14	MT-SP1/Matriptase
  Cathepsin C	MMP15	TMPRSS2
  Cathepsin K	MMP16	TMPRSS3
  Cathepsin L	MMP17	TMPRSS4
  Cathepsin S	MMP19
  Cathepsin V/L2	MMP20
  Cathepsin X/Z/P	MMP23
  	MMP24
  	MMP26
  	MMP27

• The activatable anti-PD-1 antibodies described herein overcome a limitation of antibody therapeutics, particularly antibody therapeutics that are known to be toxic to at least some degree in vivo. Target-mediated toxicity constitutes a major limitation for the development of therapeutic antibodies. The activatable anti-PD-1 antibodies provided herein are designed to address the toxicity associated with the inhibition of the target in normal tissues by traditional therapeutic antibodies. These activatable anti-PD-1 antibodies remain masked until proteolytically activated at the site of disease. Starting with an anti-PD-1 antibody as a parental therapeutic antibody, the activatable anti-PD-1 antibodies of the invention were engineered by coupling the antibody to an inhibitory mask through a linker that incorporates a protease substrate.
• When the AB is modified with a MM and is in the presence of the target, specific binding of the AB to its target is reduced or inhibited, as compared to the specific binding of the AB not modified with an MM or the specific binding of the parental AB to the target.
• The K_d of the AB modified with a MM towards the target is at least 5, 10, 25, 50, 100, 250, 500, 1,000, 2,500, 5,000, 10,000, 50,000, 100,000, 500,000, 1,000,000, 5,000,000, 10,000,000, 50,000,000 or greater, or between 5-10, 10-100, 10-1,000, 10-10,000, 10-100,000, 10-1,000,000, 10-10,000,000, 100-1,000, 100-10,000, 100-100,000, 100-1,000,000, 100-10,000,000, 1,000-10,000, 1,000-100,000, 1,000-1,000,000, 1000-10,000,000, 10,000-100,000, 10,000-1,000,000, 10,000-10,000,000, 100,000-1,000,000, or 100,000-10,000,000 times greater than the K_d of the AB not modified with an MM or of the parental AB towards the target. Conversely, the binding affinity of the AB modified with a MM towards the target is at least 2, 3, 4, 5, 10, 25, 50, 100, 250, 500, 1,000, 2,500, 5,000, 10,000, 50,000, 100,000, 500,000, 1,000,000, 5,000,000, 10,000,000, 50,000,000 or greater, or between 5-10, 10-100, 10-1,000, 10-10,000, 10-100,000, 10-1,000,000, 10-10,000,000, 100-1,000, 100-10,000, 100-100,000, 100-1,000,000, 100-10,000,000, 1,000-10,000, 1,000-100,000, 1,000-1,000,000, 1000-10,000,000, 10,000-100,000, 10,000-1,000,000, 10,000-10,000,000, 100,000-1,000,000, or 100,000-10,000,000 times lower than the binding affinity of the AB not modified with an MM or of the parental AB towards the target.
• In some embodiments, the dissociation constant (K_d) of the MM towards the AB is generally greater than the K_d of the AB towards the target. The K_d of the MM towards the AB can be at least 5, 10, 25, 50, 100, 250, 500, 1,000, 2,500, 5,000, 10,000, 100,000, 1,000,000 or even 10,000,000 times greater than the K_d of the AB towards the target. Conversely, the binding affinity of the MM towards the AB is generally lower than the binding affinity of the AB towards the target. The binding affinity of MM towards the AB can be at least 5, 10, 25, 50, 100, 250, 500, 1,000, 2,500, 5,000, 10,000, 100,000, 1,000,000 or even 10,000,000 times lower than the binding affinity of the AB towards the target.
• In some embodiments, the dissociation constant (K_d) of the MM towards the AB is approximately equal to the K_d of the AB towards the target. In some embodiments, the dissociation constant (K_d) of the MM towards the AB is no more than the dissociation constant of the AB towards the target.
• In some embodiments, the dissociation constant (K_d) of the MM towards the AB is less than the dissociation constant of the AB towards the target.
• In some embodiments, the dissociation constant (K_d) of the MM towards the AB is greater than the dissociation constant of the AB towards the target.
• In some embodiments, the MM has a K_d for binding to the AB that is no more than the K_d for binding of the AB to the target.
• In some embodiments, the MM has a K_d for binding to the AB that is no less than the K_d for binding of the AB to the target.
• In some embodiments, the MM has a K_d for binding to the AB that is approximately equal to the K_d for binding of the AB to the target.
• In some embodiments, the MM has a K_d for binding to the AB that is less than the K_d for binding of the AB to the target.
• In some embodiments, the MM has a K_d for binding to the AB that is greater than the K_d for binding of the AB to the target.
• In some embodiments, the MM has a K_d for binding to the AB that is no more than 2, 3, 4, 5, 10, 25, 50, 100, 250, 500, or 1,000 fold greater than the K_d for binding of the AB to the target. In some embodiments, the MM has a K_d for binding to the AB that is between 1-5, 2-5, 2-10, 5-10, 5-20, 5-50, 5-100, 10-100, 10-1,000, 20-100, 20-1000, or 100-1,000 fold greater than the K_d for binding of the AB to the target.
• In some embodiments, the MM has an affinity for binding to the AB that is less than the affinity of binding of the AB to the target.
• In some embodiments, the MM has an affinity for binding to the AB that is no more than the affinity of binding of the AB to the target.
• In some embodiments, the MM has an affinity for binding to the AB that is approximately equal of the affinity of binding of the AB to the target.
• In some embodiments, the MM has an affinity for binding to the AB that is no less than the affinity of binding of the AB to the target.
• In some embodiments, the MM has an affinity for binding to the AB that is greater than the affinity of binding of the AB to the target.
• In some embodiments, the MM has an affinity for binding to the AB that is 2, 3, 4, 5, 10, 25, 50, 100, 250, 500, or 1,000 less than the affinity of binding of the AB to the target. I In some embodiments, the MM has an affinity for binding to the AB that is between 1-5, 2-5, 2-10, 5-10, 5-20, 5-50, 5-100, 10-100, 10-1,000, 20-100, 20-1000, or 100-1,000 fold less than the affinity of binding of the AB to the target. In some embodiments, the MM has an affinity for binding to the AB that is 2 to 20 fold less than the affinity of binding of the AB to the target. In some embodiments, a MM not covalently linked to the AB and at equimolar concentration to the AB does not inhibit the binding of the AB to the target.
• When the AB is modified with a MM and is in the presence of the target specific binding of the AB to its target is reduced or inhibited, as compared to the specific binding of the AB not modified with an MM or the specific binding of the parental AB to the target. When compared to the binding of the AB not modified with an MM or the binding of the parental AB to the target the AB's ability to bind the target when modified with an MM can be reduced by at least 50%, 60%, 70%, 80%, 90%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% and even 100% for at least 2, 4, 6, 8, 12, 28, 24, 30, 36, 48, 60, 72, 84, or 96 hours, or 5, 10, 15, 30, 45, 60, 90, 120, 150, or 180 days, or 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, or 12 months or more when measured in vivo or in an in vitro assay.
• The MM inhibits the binding of the AB to the target. The MM binds the antigen binding domain of the AB and inhibits binding of the AB to the target. The MM can sterically inhibit the binding of the AB to the target. The MM can allosterically inhibit the binding of the AB to its target. In these embodiments when the AB is modified or coupled to a MM and in the presence of target there is no binding or substantially no binding of the AB to the target, or no more than 0.001%, 0.01%, 0.1%, 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, or 50% binding of the AB to the target, as compared to the binding of the AB not modified with an MM, the parental AB, or the AB not coupled to an MM to the target, for at least 2, 4, 6, 8, 12, 28, 24, 30, 36, 48, 60, 72, 84, or 96 hours, or 5, 10, 15, 30, 45, 60, 90, 120, 150, or 180 days, or 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, or 12 months or longer when measured in vivo or in an in vitro assay.
• When an AB is coupled to or modified by a MM, the MM ‘masks’ or reduces or otherwise inhibits the specific binding of the AB to the target. When an AB is coupled to or modified by a MM, such coupling or modification can effect a structural change that reduces or inhibits the ability of the AB to specifically bind its target.
• An AB coupled to or modified with an MM can be represented by the following formulae (in order from an amino (N) terminal region to carboxyl (C) terminal region:
• 
  (MM)-(AB)
• 
  (AB)-(MM)
• 
  (MM)-L-(AB)
• 
  (AB)-L-(MM)
• where MM is a masking moiety, the AB is an antibody or antibody fragment thereof, and the L is a linker. In many embodiments, it can be desirable to insert one or more linkers, e.g., flexible linkers, into the composition so as to provide for flexibility.
• In certain embodiments, the MM is not a natural binding partner of the AB. In some embodiments, the MM contains no or substantially no homology to any natural binding partner of the AB. In some embodiments, the MM is no more than 5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, or 80% similar to any natural binding partner of the AB. In some embodiments, the MM is no more than 5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, or 80% identical to any natural binding partner of the AB. In some embodiments, the MM is no more than 25% identical to any natural binding partner of the AB. In some embodiments, the MM is no more than 50% identical to any natural binding partner of the AB. In some embodiments, the MM is no more than 20% identical to any natural binding partner of the AB. In some embodiments, the MM is no more than 10% identical to any natural binding partner of the AB.
• In some embodiments, the activatable antibodies include an AB that is modified by an MM and also includes one or more cleavable moieties (CM). Such activatable antibodies exhibit activatable/switchable binding, to the AB's target. Activatable antibodies generally include an antibody or antibody fragment (AB), modified by or coupled to a masking moiety (MM) and a modifiable or cleavable moiety (CM). In some embodiments, the CM contains an amino acid sequence that serves as a substrate for at least one protease.
• The elements of the activatable antibodies are arranged so that the MM and CM are positioned such that in a cleaved (or relatively active) state and in the presence of a target, the AB binds a target while the activatable antibody is in an uncleaved (or relatively inactive) state in the presence of the target, specific binding of the AB to its target is reduced or inhibited. The specific binding of the AB to its target can be reduced due to the inhibition or masking of the AB's ability to specifically bind its target by the MM.
• The K_d of the AB modified with a MM and a CM towards the target is at least 5, 10, 25, 50, 100, 250, 500, 1,000, 2,500, 5,000, 10,000, 50,000, 100,000, 500,000, 1,000,000, 5,000,000, 10,000,000, 50,000,000 or greater, or between 5-10, 10-100, 10-1,000, 10-10,000, 10-100,000, 10-1,000,000, 10-10,000,000, 100-1,000, 100-10,000, 100-100,000, 100-1,000,000, 100-10,000,000, 1,000-10,000, 1,000-100,000, 1,000-1,000,000, 1000-10,000,000, 10,000-100,000, 10,000-1,000,000, 10,000-10,000,000, 100,000-1,000,000, or 100,000-10,000,000 times greater than the K_d of the AB not modified with an MM and a CM or of the parental AB towards the target. Conversely, the binding affinity of the AB modified with a MM and a CM towards the target is at least 5, 10, 25, 50, 100, 250, 500, 1,000, 2,500, 5,000, 10,000, 50,000, 100,000, 500,000, 1,000,000, 5,000,000, 10,000,000, 50,000,000 or greater, or between 5-10, 10-100, 10-1,000, 10-10,000, 10-100,000, 10-1,000,000, 10-10,000,000, 100-1,000, 100-10,000, 100-100,000, 100-1,000,000, 100-10,000,000, 1,000-10,000, 1,000-100,000, 1,000-1,000,000, 1000-10,000,000, 10,000-100,000, 10,000-1,000,000, 10,000-10,000,000, 100,000-1,000,000, or 100,000-10,000,000 times lower than the binding affinity of the AB not modified with an MM and a CM or of the parental AB towards the target.
• When the AB is modified with a MM and a CM and is in the presence of the target but not in the presence of a modifying agent (for example at least one protease), specific binding of the AB to its target is reduced or inhibited, as compared to the specific binding of the AB not modified with an MM and a CM or of the parental AB to the target. When compared to the binding of the parental AB or the binding of an AB not modified with an MM and a CM to its target, the AB's ability to bind the target when modified with an MM and a CM can be reduced by at least 50%, 60%, 70%, 80%, 90%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% and even 100% for at least 2, 4, 6, 8, 12, 28, 24, 30, 36, 48, 60, 72, 84, or 96 hours or 5, 10, 15, 30, 45, 60, 90, 120, 150, or 180 days, or 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, or 12 months or longer when measured in vivo or in an in vitro assay.
• As used herein, the term cleaved state refers to the condition of the activatable antibodies following modification of the CM by at least one protease. The term uncleaved state, as used herein, refers to the condition of the activatable antibodies in the absence of cleavage of the CM by a protease. As discussed above, the term “activatable antibodies” is used herein to refer to an activatable antibody in both its uncleaved (native) state, as well as in its cleaved state. It will be apparent to the ordinarily skilled artisan that in some embodiments a cleaved activatable antibody can lack an MM due to cleavage of the CM by protease, resulting in release of at least the MM (e.g., where the MM is not joined to the activatable antibodies by a covalent bond (e.g., a disulfide bond between cysteine residues).
• By activatable or switchable is meant that the activatable antibody exhibits a first level of binding to a target when the activatable antibody is in a inhibited, masked or uncleaved state (i.e., a first conformation), and a second level of binding to the target in the uninhibited, unmasked and/or cleaved state (i.e., a second conformation), where the second level of target binding is greater than the first level of binding. In general, the access of target to the AB of the activatable antibody is greater in the presence of a cleaving agent capable of cleaving the CM, i.e., a protease, than in the absence of such a cleaving agent. Thus, when the activatable antibody is in the uncleaved state, the AB is inhibited from target binding and can be masked from target binding (i.e., the first conformation is such the AB cannot bind the target), and in the cleaved state the AB is not inhibited or is unmasked to target binding.
• The CM and AB of the activatable antibodies are selected so that the AB represents a binding moiety for a given target, and the CM represents a substrate for a protease. In some embodiments, the protease is co-localized with the target at a treatment site or diagnostic site in a subject. As used herein, co-localized refers to being at the same site or relatively close nearby. In some embodiments, a protease cleaves a CM yielding an activated antibody that binds to a target located nearby the cleavage site. The activatable antibodies disclosed herein find particular use where, for example, a protease capable of cleaving a site in the CM, i.e., a protease, is present at relatively higher levels in or in close proximity to target-containing tissue of a treatment site or diagnostic site than in tissue of non-treatment sites (for example in healthy tissue). In some embodiments, a CM of the disclosure is also cleaved by one or more other proteases. In some embodiments, it is the one or more other proteases that is co-localized with the target and that is responsible for cleavage of the CM in vivo.
• In some embodiments activatable antibodies provide for reduced toxicity and/or adverse side effects that could otherwise result from binding of the AB at non-treatment sites if the AB were not masked or otherwise inhibited from binding to the target.
• In general, an activatable antibody can be designed by selecting an AB of interest and constructing the remainder of the activatable antibody so that, when conformationally constrained, the MM provides for masking of the AB or reduction of binding of the AB to its target. Structural design criteria can be to be taken into account to provide for this functional feature.
• Activatable antibodies exhibiting a switchable phenotype of a desired dynamic range for target binding in an inhibited versus an uninhibited conformation are provided. Dynamic range generally refers to a ratio of (a) a maximum detected level of a parameter under a first set of conditions to (b) a minimum detected value of that parameter under a second set of conditions. For example, in the context of an activatable antibody, the dynamic range refers to the ratio of (a) a maximum detected level of target protein binding to an activatable antibody in the presence of at least one protease capable of cleaving the CM of the activatable antibodies to (b) a minimum detected level of target protein binding to an activatable antibody in the absence of the protease. The dynamic range of an activatable antibody can be calculated as the ratio of the dissociation constant of an activatable antibody cleaving agent (e.g., enzyme) treatment to the dissociation constant of the activatable antibodies cleaving agent treatment. The greater the dynamic range of an activatable antibody, the better the switchable phenotype of the activatable antibody. Activatable antibodies having relatively higher dynamic range values (e.g., greater than 1) exhibit more desirable switching phenotypes such that target protein binding by the activatable antibodies occurs to a greater extent (e.g., predominantly occurs) in the presence of a cleaving agent (e.g., enzyme) capable of cleaving the CM of the activatable antibodies than in the absence of a cleaving agent.
• Activatable antibodies can be provided in a variety of structural configurations. Exemplary formulae for activatable antibodies are provided below. It is specifically contemplated that the N- to C-terminal order of the AB, MM and CM can be reversed within an activatable antibody. It is also specifically contemplated that the CM and MM can overlap in amino acid sequence, e.g., such that the CM is contained within the MM.
• For example, activatable antibodies can be represented by the following formula (in order from an amino (N) terminal region to carboxyl (C) terminal region:
• 
  (MM)-(CM)-(AB)
• 
  (AB)-(CM)-(MM)
• where MM is a masking moiety, CM is a cleavable moiety, and AB is an antibody or fragment thereof. It should be noted that although MM and CM are indicated as distinct components in the formulae above, in all exemplary embodiments (including formulae) disclosed herein it is contemplated that the amino acid sequences of the MM and the CM could overlap, e.g., such that the CM is completely or partially contained within the MM. In addition, the formulae above provide for additional amino acid sequences that can be positioned N-terminal or C-terminal to the activatable antibodies elements.
• In certain embodiments, the MM is not a natural binding partner of the AB. In some embodiments, the MM contains no or substantially no homology to any natural binding partner of the AB. In some embodiments, the MM is no more than 5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, or 80% similar to any natural binding partner of the AB. In some embodiments, the MM is no more than 5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, or 80% identical to any natural binding partner of the AB. In some embodiments, the MM is no more than 50% identical to any natural binding partner of the AB. In some embodiments, the MM is no more than 25% identical to any natural binding partner of the AB. In some embodiments, the MM is no more than 20% identical to any natural binding partner of the AB. In some embodiments, the MM is no more than 10% identical to any natural binding partner of the AB.
• In many embodiments it can be desirable to insert one or more linkers, e.g., flexible linkers, into the activatable antibody construct so as to provide for flexibility at one or more of the MM-CM junction, the CM-AB junction, or both. For example, the AB, MM, and/or CM may not contain a sufficient number of residues (e.g., Gly, Ser, Asp, Asn, especially Gly and Ser, particularly Gly) to provide the desired flexibility. As such, the switchable phenotype of such activatable antibody constructs can benefit from introduction of one or more amino acids to provide for a flexible linker. In addition, as described below, where the activatable antibody is provided as a conformationally constrained construct, a flexible linker can be operably inserted to facilitate formation and maintenance of a cyclic structure in the uncleaved activatable antibody.
• For example, in certain embodiments an activatable antibody comprises one of the following formulae (where the formula below represent an amino acid sequence in either N- to C-terminal direction or C- to N-terminal direction):
• 
  (MM)-L1-(CM)-(AB)
• 
  (MM)-(CM)-L2-(AB)
• 
  (MM)-L1-(CM)-L2-(AB)
• wherein MM, CM, and AB are as defined above; wherein L1 and L2 are each independently and optionally present or absent, are the same or different flexible linkers that include at least 1 flexible amino acid (e.g., Gly). In addition, the formulae above provide for additional amino acid sequences that can be positioned N-terminal or C-terminal to the activatable antibodies elements. Examples include, but are not limited to, targeting moieties (e.g., a ligand for a receptor of a cell present in a target tissue) and serum half-life extending moieties (e.g., polypeptides that bind serum proteins, such as immunoglobulin (e.g., IgG) or serum albumin (e.g., human serum albumin (HAS)).
• The CM is specifically cleaved by at least one protease at a rate of about 0.001-1500×10⁴M⁻¹S⁻¹ or at least 0.001, 0.005, 0.01, 0.05, 0.1, 0.5, 1, 2.5, 5, 7.5, 10, 15, 20, 25, 50, 75, 100, 125, 150, 200, 250, 500, 750, 1000, 1250, or 1500×10⁴ M⁻¹S⁻¹. In some embodiments, the CM is specifically cleaved at a rate of about 100,000 M⁻¹S⁻¹. In some embodiments, the CM is specifically cleaved at a rate from about 1×10E2 to about 1×10E6 M⁻¹S⁻¹ (i.e., from about 1×10² to about 1×10⁶M⁻¹S⁻¹).
• For specific cleavage by an enzyme, contact between the enzyme and CM is made. When the activatable antibody comprising an AB coupled to a MM and a CM is in the presence of target and sufficient enzyme activity, the CM can be cleaved. Sufficient enzyme activity can refer to the ability of the enzyme to make contact with the CM and effect cleavage. It can readily be envisioned that an enzyme can be in the vicinity of the CM but unable to cleave because of other cellular factors or protein modification of the enzyme.
• Linkers suitable for use in compositions described herein are generally ones that provide flexibility of the modified AB or the activatable antibodies to facilitate the inhibition of the binding of the AB to the target. Such linkers are generally referred to as flexible linkers. Suitable linkers can be readily selected and can be of any of a suitable of different lengths, such as from 1 amino acid (e.g., Gly) to 20 amino acids, from 2 amino acids to 15 amino acids, from 3 amino acids to 12 amino acids, including 4 amino acids to 10 amino acids, 5 amino acids to 9 amino acids, 6 amino acids to 8 amino acids, or 7 amino acids to 8 amino acids, and can be 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, or 20 amino acids in length.
• Exemplary flexible linkers include glycine polymers (G)n, glycine-serine polymers (including, for example, (GS)n, (GSGGS) n (SEQ ID NO: 363) and (GGGS)n (SEQ ID NO: 364), where n is an integer of at least one), glycine-alanine polymers, alanine-serine polymers, and other flexible linkers known in the art. Glycine and glycine-serine polymers are relatively unstructured, and therefore can be able to serve as a neutral tether between components. Glycine accesses significantly more phi-psi space than even alanine, and is much less restricted than residues with longer side chains (see Scheraga, Rev. Computational Chem. 11173-142 (1992)). Exemplary flexible linkers include, but are not limited to GGSG (SEQ ID NO: 365), GGSGG (SEQ ID NO: 366), GSGSG (SEQ ID NO: 367), GSGGG (SEQ ID NO: 368), GGGSG (SEQ ID NO: 369), GSSSG (SEQ ID NO: 370), and the like. The ordinarily skilled artisan will recognize that design of an activatable antibodies can include linkers that are all or partially flexible, such that the linker can include a flexible linker as well as one or more portions that confer less flexible structure to provide for a desired activatable antibodies structure.
• The disclosure also provides compositions and methods that include an activatable anti-PD-1 antibody that includes an antibody or antibody fragment (AB) that specifically binds PD-1, where the AB is coupled to a masking moiety (MM) that decreases the ability of the AB to bind its target. In some embodiments, the activatable anti-PD-1 antibody further includes a cleavable moiety (CM) that is a substrate for a protease. The compositions and methods provided herein enable the attachment of one or more agents to one or more cysteine residues in the AB without compromising the activity (e.g., the masking, activating or binding activity) of the activatable anti-PD-1 antibody. In some embodiments, the compositions and methods provided herein enable the attachment of one or more agents to one or more cysteine residues in the AB without reducing or otherwise disturbing one or more disulfide bonds within the MM. The compositions and methods provided herein produce an activatable anti-PD-1 antibody that is conjugated to one or more agents, e.g., any of a variety of therapeutic, diagnostic and/or prophylactic agents, for example, in some embodiments, without any of the agent(s) being conjugated to the MM of the activatable anti-PD-1 antibody. The compositions and methods provided herein produce conjugated activatable anti-PD-1 antibodies in which the MM retains the ability to effectively and efficiently mask the AB of the activatable antibody in an uncleaved state. The compositions and methods provided herein produce conjugated activatable anti-PD-1 antibodies in which the activatable antibody is still activated, i.e., cleaved, in the presence of a protease that can cleave the CM.
• The activatable anti-PD-1 antibodies have at least one point of conjugation for an agent, but in the methods and compositions provided herein less than all possible points of conjugation are available for conjugation to an agent. In some embodiments, the one or more points of conjugation are sulfur atoms involved in disulfide bonds. In some embodiments, the one or more points of conjugation are sulfur atoms involved in interchain disulfide bonds. In some embodiments, the one or more points of conjugation are sulfur atoms involved in interchain sulfide bonds, but not sulfur atoms involved in intrachain disulfide bonds. In some embodiments, the one or more points of conjugation are sulfur atoms of cysteine or other amino acid residues containing a sulfur atom. Such residues can occur naturally in the antibody structure or can be incorporated into the antibody by site-directed mutagenesis, chemical conversion, or mis-incorporation of non-natural amino acids.
• Also provided are methods of preparing a conjugate of an activatable anti-PD-1 antibody having one or more interchain disulfide bonds in the AB and one or more intrachain disulfide bonds in the MM, and a drug reactive with free thiols is provided. The method generally includes partially reducing interchain disulfide bonds in the activatable antibody with a reducing agent, such as, for example, TCEP; and conjugating the drug reactive with free thiols to the partially reduced activatable antibody. As used herein, the term partial reduction refers to situations where an activatable anti-PD-1 antibody is contacted with a reducing agent and less than all disulfide bonds, e.g., less than all possible sites of conjugation are reduced. In some embodiments, less than 99%, 98%, 97%, 96%, 95%, 90%, 85%, 80%, 75%, 70%, 65%, 60%, 55%, 50%, 45%, 40%, 35%, 30%, 25%, 20%, 15%, 10% or less than 5% of all possible sites of conjugation are reduced.
• In yet other embodiments, a method of reducing and conjugating an agent, e.g., a drug, to an activatable anti-PD-1 antibody resulting in selectivity in the placement of the agent is provided. The method generally includes partially reducing the activatable anti-PD-1 antibody with a reducing agent such that any conjugation sites in the masking moiety or other non-AB portion of the activatable antibody are not reduced, and conjugating the agent to interchain thiols in the AB. The conjugation site(s) are selected so as to allow desired placement of an agent to allow conjugation to occur at a desired site. The reducing agent is, for example, TCEP. The reduction reaction conditions such as, for example, the ratio of reducing agent to activatable antibody, the length of incubation, the temperature during the incubation, the pH of the reducing reaction solution, etc., are determined by identifying the conditions that produce a conjugated activatable antibody in which the MM retains the ability to effectively and efficiently mask the AB of the activatable antibody in an uncleaved state. The ratio of reduction agent to activatable anti-PD-1 antibody will vary depending on the activatable antibody. In some embodiments, the ratio of reducing agent to activatable anti-PD-1 antibody will be in a range from about 20:1 to 1:1, from about 10:1 to 1:1, from about 9:1 to 1:1, from about 8:1 to 1:1, from about 7:1 to 1:1, from about 6:1 to 1:1, from about 5:1 to 1:1, from about 4:1 to 1:1, from about 3:1 to 1:1, from about 2:1 to 1:1, from about 20:1 to 1:1.5, from about 10:1 to 1:1.5, from about 9:1 to 1:1.5, from about 8:1 to 1:1.5, from about 7:1 to 1:1.5, from about 6:1 to 1:1.5, from about 5:1 to 1:1.5, from about 4:1 to 1:1.5, from about 3:1 to 1:1.5, from about 2:1 to 1:1.5, from about 1.5:1 to 1:1.5, or from about 1:1 to 1:1.5. In some embodiments, the ratio is in a range of from about 5:1 to 1:1. In some embodiments, the ratio is in a range of from about 5:1 to 1.5:1. In some embodiments, the ratio is in a range of from about 4:1 to 1:1. In some embodiments, the ratio is in a range from about 4:1 to 1.5:1. In some embodiments, the ratio is in a range from about 8:1 to about 1:1. In some embodiments, the ratio is in a range of from about 2.5:1 to 1:1.
• In some embodiments, a method of reducing interchain disulfide bonds in the AB of an activatable anti-PD-1 antibody and conjugating an agent, e.g., a thiol-containing agent such as a drug, to the resulting interchain thiols to selectively locate agent(s) on the AB is provided. The method generally includes partially reducing the AB with a reducing agent to form at least two interchain thiols without forming all possible interchain thiols in the activatable antibody; and conjugating the agent to the interchain thiols of the partially reduced AB. For example, the AB of the activatable antibody is partially reduced for about 1 hour at about 37° C. at a desired ratio of reducing agent:activatable antibody. In some embodiments, the ratio of reducing agent to activatable antibody will be in a range from about 20:1 to 1:1, from about 10:1 to 1:1, from about 9:1 to 1:1, from about 8:1 to 1:1, from about 7:1 to 1:1, from about 6:1 to 1:1, from about 5:1 to 1:1, from about 4:1 to 1:1, from about 3:1 to 1:1, from about 2:1 to 1:1, from about 20:1 to 1:1.5, from about 10:1 to 1:1.5, from about 9:1 to 1:1.5, from about 8:1 to 1:1.5, from about 7:1 to 1:1.5, from about 6:1 to 1:1.5, from about 5:1 to 1:1.5, from about 4:1 to 1:1.5, from about 3:1 to 1:1.5, from about 2:1 to 1:1.5, from about 1.5:1 to 1:1.5, or from about 1:1 to 1:1.5. In some embodiments, the ratio is in a range of from about 5:1 to 1:1. In some embodiments, the ratio is in a range of from about 5:1 to 1.5:1. In some embodiments, the ratio is in a range of from about 4:1 to 1:1. In some embodiments, the ratio is in a range from about 4:1 to 1.5:1. In some embodiments, the ratio is in a range from about 8:1 to about 1:1. In some embodiments, the ratio is in a range of from about 2.5:1 to 1:1.
• The thiol-containing reagent can be, for example, cysteine or N-acetyl cysteine. The reducing agent can be, for example, TCEP. In some embodiments, the reduced activatable antibody can be purified prior to conjugation, using for example, column chromatography, dialysis, or diafiltration. Alternatively, the reduced antibody is not purified after partial reduction and prior to conjugation.
• The invention also provides partially reduced activatable anti-PD-1 antibodies in which at least one interchain disulfide bond in the activatable antibody has been reduced with a reducing agent without disturbing any intrachain disulfide bonds in the activatable antibody, wherein the activatable antibody includes an antibody or an antigen binding fragment thereof (AB) that specifically binds to PD-1, a masking moiety (MM) that inhibits the binding of the AB of the activatable antibody in an uncleaved state to the PD-1 target, and a cleavable moiety (CM) coupled to the AB, wherein the CM is a polypeptide that functions as a substrate for a protease. In some embodiments the MM is coupled to the AB via the CM. In some embodiments, one or more intrachain disulfide bond(s) of the activatable antibody is not disturbed by the reducing agent. In some embodiments, one or more intrachain disulfide bond(s) of the MM within the activatable antibody is not disturbed by the reducing agent. In some embodiments, the activatable antibody in the uncleaved state has the structural arrangement from N-terminus to C-terminus as follows: MM-CM-AB or AB-CM-MM. In some embodiments, reducing agent is TCEP.
• The disclosure also provides partially reduced activatable antibodies in which at least one interchain disulfide bond in the activatable antibody has been reduced with a reducing agent without disturbing any intrachain disulfide bonds in the activatable antibody, wherein the activatable antibody includes an antibody or an antigen binding fragment thereof (AB) that specifically binds to the target, e.g., PD-1, a masking moiety (MM) that inhibits the binding of the AB of the activatable antibody in an uncleaved state to the target, and a cleavable moiety (CM) coupled to the AB, wherein the CM is a polypeptide that functions as a substrate for at least one protease. In some embodiments, the MM is coupled to the AB via the CM. In some embodiments, one or more intrachain disulfide bond(s) of the activatable antibody is not disturbed by the reducing agent. In some embodiments, one or more intrachain disulfide bond(s) of the MM within the activatable antibody is not disturbed by the reducing agent. In some embodiments, the activatable antibody in the uncleaved state has the structural arrangement from N-terminus to C-terminus as follows: MM-CM-AB or AB-CM-MM. In some embodiments, reducing agent is TCEP.
• In some embodiments, the activatable antibodies described herein also include an agent conjugated to the activatable antibody. In some embodiments, the conjugated agent is a therapeutic agent, such as an anti-inflammatory. In such embodiments, the agent is conjugated to a carbohydrate moiety of the activatable antibody, for example, in some embodiments, where the carbohydrate moiety is located outside the antigen-binding region of the antibody or antigen-binding fragment in the activatable antibody. In some embodiments, the agent is conjugated to a sulfhydryl group of the antibody or antigen-binding fragment in the activatable antibody.
• In some embodiments, the agent is a detectable moiety such as, for example, a label or other marker. For example, the agent is or includes a radiolabeled amino acid, one or more biotinyl moieties that can be detected by marked avidin (e.g., streptavidin containing a fluorescent marker or enzymatic activity that can be detected by optical or calorimetric methods), one or more radioisotopes or radionuclides, one or more fluorescent labels, one or more enzymatic labels, and/or one or more chemiluminescent agents. In some embodiments, detectable moieties are attached by spacer molecules.
• Those of ordinary skill in the art will recognize that a large variety of possible moieties can be coupled to the resultant antibodies of the disclosure. (See, for example, “Conjugate Vaccines”, Contributions to Microbiology and Immunology, J. M. Cruse and R. E. Lewis, Jr (eds), Carger Press, New York, (1989), the entire contents of which are incorporated herein by reference).
• Coupling can be accomplished by any chemical reaction that will bind the two molecules so long as the antibody and the other moiety retain their respective activities. This linkage can include many chemical mechanisms, for instance covalent binding, affinity binding, intercalation, coordinate binding and complexation. In some embodiments, the binding is, however, covalent binding. Covalent binding can be achieved either by direct condensation of existing side chains or by the incorporation of external bridging molecules. Many bivalent or polyvalent linking agents are useful in coupling protein molecules, such as the antibodies of the present disclosure, to other molecules. For example, representative coupling agents can include organic compounds such as thioesters, carbodiimides, succinimide esters, diisocyanates, glutaraldehyde, diazobenzenes and hexamethylene diamines. This listing is not intended to be exhaustive of the various classes of coupling agents known in the art but, rather, is exemplary of the more common coupling agents. (See Killen and Lindstrom, Jour. Immun. 133:1335-2549 (1984); Jansen et al., Immunological Reviews 62:185-216 (1982); and Vitetta et al., Science 238:1098 (1987).
• In some embodiments, in addition to the compositions and methods provided herein, the conjugated activatable antibody can also be modified for site-specific conjugation through modified amino acid sequences inserted or otherwise included in the activatable antibody sequence. These modified amino acid sequences are designed to allow for controlled placement and/or dosage of the conjugated agent within a conjugated activatable antibody. For example, the activatable antibody can be engineered to include cysteine substitutions at positions on light and heavy chains that provide reactive thiol groups and do not negatively impact protein folding and assembly, nor alter antigen binding. In some embodiments, the activatable antibody can be engineered to include or otherwise introduce one or more non-natural amino acid residues within the activatable antibody to provide suitable sites for conjugation. In some embodiments, the activatable antibody can be engineered to include or otherwise introduce enzymatically activatable peptide sequences within the activatable antibody sequence.
• Suitable linkers are described in the literature. (See, for example, Ramakrishnan, S. et al., Cancer Res. 44:201-208 (1984) describing use of MBS (M-maleimidobenzoyl-N-hydroxysuccinimide ester). See also, U.S. Pat. No. 5,030,719, describing use of halogenated acetyl hydrazide derivative coupled to an antibody by way of an oligopeptide linker. In some embodiments, suitable linkers include: (i) EDC (1-ethyl-3-(3-dimethylamino-propyl) carbodiimide hydrochloride; (ii) SMPT (4-succinimidyloxycarbonyl-alpha-methyl-alpha-(2-pridyl-dithio)-toluene (Pierce Chem. Co., Cat. (21558G); (iii) SPDP (succinimidyl-6 [3-(2-pyridyldithio) propionamido]hexanoate (Pierce Chem. Co., Cat #21651G); (iv) Sulfo-LC-SPDP (sulfosuccinimidyl 6 [3-(2-pyridyldithio)-propianamide] hexanoate (Pierce Chem. Co. Cat. #2165-G); and (v) sulfo-NHS (N-hydroxysulfo-succinimide: Pierce Chem. Co., Cat. #24510) conjugated to EDC. Additional linkers include, but are not limited to, SMCC, sulfo-SMCC, SPDB, or sulfo-SPDB.
• The linkers described above contain components that have different attributes, thus leading to conjugates with differing physio-chemical properties. For example, sulfo-NHS esters of alkyl carboxylates are more stable than sulfo-NHS esters of aromatic carboxylates. NETS-ester containing linkers are less soluble than sulfo-NHS esters. Further, the linker SMPT contains a sterically hindered disulfide bond, and can form conjugates with increased stability. Disulfide linkages, are in general, less stable than other linkages because the disulfide linkage is cleaved in vitro, resulting in less conjugate available. Sulfo-NHS, in particular, can enhance the stability of carbodimide couplings. Carbodimide couplings (such as EDC) when used in conjunction with sulfo-NHS, forms esters that are more resistant to hydrolysis than the carbodimide coupling reaction alone.
• In some embodiments, the linkers are cleavable. In some embodiments, the linkers are non-cleavable. In some embodiments, two or more linkers are present. The two or more linkers are all the same, i.e., cleavable or non-cleavable, or the two or more linkers are different, i.e., at least one cleavable and at least one non-cleavable.
• The present disclosure utilizes several methods for attaching agents to ABs: (a) attachment to the carbohydrate moieties of the AB, or (b) attachment to sulfhydryl groups of the AB, or (c) attachment to amino groups of the AB, or (d) attachment to carboxylate groups of the AB. According to the disclosure, ABs can be covalently attached to an agent through an intermediate linker having at least two reactive groups, one to react with AB and one to react with the agent. The linker, which can include any compatible organic compound, can be chosen such that the reaction with AB (or agent) does not adversely affect AB reactivity and selectivity. Furthermore, the attachment of linker to agent might not destroy the activity of the agent. Suitable linkers for reaction with oxidized antibodies or oxidized antibody fragments include those containing an amine selected from the group consisting of primary amine, secondary amine, hydrazine, hydrazide, hydroxylamine, phenylhydrazine, semicarbazide and thiosemicarbazide groups. Such reactive functional groups can exist as part of the structure of the linker, or can be introduced by suitable chemical modification of linkers not containing such groups.
• According to the present disclosure, suitable linkers for attachment to reduced ABs include those having certain reactive groups capable of reaction with a sulfhydryl group of a reduced antibody or fragment. Such reactive groups include, but are not limited to: reactive haloalkyl groups (including, for example, haloacetyl groups), p-mercuribenzoate groups and groups capable of Michael-type addition reactions (including, for example, maleimides and groups of the type described by Mitra and Lawton, 1979, J. Amer. Chem. Soc. 101: 3097-3110).
• According to the present disclosure, suitable linkers for attachment to neither oxidized nor reduced Abs include those having certain functional groups capable of reaction with the primary amino groups present in unmodified lysine residues in the Ab. Such reactive groups include, but are not limited to, NHS carboxylic or carbonic esters, sulfo-NHS carboxylic or carbonic esters, 4-nitrophenyl carboxylic or carbonic esters, pentafluorophenyl carboxylic or carbonic esters, acyl imidazoles, isocyanates, and isothiocyanates.
• According to the present disclosure, suitable linkers for attachment to neither oxidized nor reduced Abs include those having certain functional groups capable of reaction with the carboxylic acid groups present in aspartate or glutamate residues in the Ab, which have been activated with suitable reagents. Suitable activating reagents include EDC, with or without added NHS or sulfo-NHS, and other dehydrating agents utilized for carboxamide formation. In these instances, the functional groups present in the suitable linkers would include primary and secondary amines, hydrazines, hydroxylamines, and hydrazides.
• The agent can be attached to the linker before or after the linker is attached to the AB. In certain applications it can be desirable to first produce an AB-linker intermediate in which the linker is free of an associated agent. Depending upon the particular application, a specific agent can then be covalently attached to the linker. In some embodiments, the AB is first attached to the MM, CM and associated linkers and then attached to the linker for conjugation purposes.
• Branched Linkers:
• In specific embodiments, branched linkers that have multiple sites for attachment of agents are utilized. For multiple site linkers, a single covalent attachment to an AB would result in an AB-linker intermediate capable of binding an agent at a number of sites. The sites can be aldehyde or sulfhydryl groups or any chemical site to which agents can be attached.
• In some embodiments, higher specific activity (or higher ratio of agents to AB) can be achieved by attachment of a single site linker at a plurality of sites on the AB. This plurality of sites can be introduced into the AB by either of two methods. First, one can generate multiple aldehyde groups and/or sulfhydryl groups in the same AB. Second, one can attach to an aldehyde or sulfhydryl of the AB a “branched linker” having multiple functional sites for subsequent attachment to linkers. The functional sites of the branched linker or multiple site linker can be aldehyde or sulfhydryl groups, or can be any chemical site to which linkers can be attached. Still higher specific activities can be obtained by combining these two approaches, that is, attaching multiple site linkers at several sites on the AB.
• Cleavable Linkers:
• Peptide linkers that are susceptible to cleavage by enzymes of the complement system, such as but not limited to u-plasminogen activator, tissue plasminogen activator, trypsin, plasmin, or another enzyme having proteolytic activity can be used in one embodiment of the present disclosure. According to one method of the present disclosure, an agent is attached via a linker susceptible to cleavage by complement. The antibody is selected from a class that can activate complement. The antibody-agent conjugate, thus, activates the complement cascade and releases the agent at the target site. According to another method of the present disclosure, an agent is attached via a linker susceptible to cleavage by enzymes having a proteolytic activity such as a u-plasminogen activator, a tissue plasminogen activator, plasmin, or trypsin.
• Non-limiting examples of cleavable linker sequences are provided in Table 5.

• TABLE 5
  Exemplary Linker Sequences for Conjugation

  Types of Cleavable Sequences	Amino Acid Sequence
  Plasmin cleavable sequences
  Pro-urokinase	PRFKIIGG (SEQ ID NO: 587)
  	PRFRIIGG (SEQ ID NO: 588)
  TGFβ	SSRHRRALD (SEQ ID NO: 589)
  Plasminogen	RKSSIIIRMRDVVL (SEQ ID NO: 590)
  Staphylokinase	SSSFDKGKYKKGDDA (SEQ ID NO: 591)
  	SSSFDKGKYKRGDDA (SEQ ID NO: 592)
  Factor Xa cleavable sequences	IEGR (SEQ ID NO: 593)
  	IDGR (SEQ ID NO: 594)
  	GGSIDGR (SEQ ID NO: 595)
  MMP cleavable sequences
  Gelatinase A	PLGLWA (SEQ ID NO: 596)
  Collagenase cleavable sequences
  Calf skin collagen (α1(I) chain)	GPQGIAGQ (SEQ ID NO: 597)
  Calf skin collagen (α2(I) chain)	GPQGLLGA (SEQ ID NO: 598)
  Bovine cartilage collagen (α1(II) chain)	GIAGQ (SEQ ID NO: 599)
  Human liver collagen (α1(III) chain)	GPLGIAGI (SEQ ID NO: 600)
  Human α2M	GPEGLRVG (SEQ ID NO: 601)
  Human PZP	YGAGLGVV (SEQ ID NO: 602)
  	AGLGVVER (SEQ ID NO: 603)
  	AGLGISST (SEQ ID NO: 604)
  Rat α1M	EPQALAMS (SEQ ID NO: 605)
  	QALAMSAI (SEQ ID NO: 606)
  Rat α2M	AAYHLVSQ (SEQ ID NO: 607)
  	MDAFLESS (SEQ ID NO: 608)
  Rat α1I3(2J)	ESLPVVAV (SEQ ID NO: 609)
  Rat α1I3(27J)	SAPAVESE (SEQ ID NO: 610)
  Human fibroblast collagenase	DVAQFVLT (SEQ ID NO: 611)
  (autolytic cleavages)	VAQFVLTE (SEQ ID NO: 612)
  	AQFVLTEG (SEQ ID NO: 613)
  	PVQPIGPQ (SEQ ID NO: 614)

• In addition, agents can be attached via disulfide bonds (for example, the disulfide bonds on a cysteine molecule) to the AB. Since many tumors naturally release high levels of glutathione (a reducing agent) this can reduce the disulfide bonds with subsequent release of the agent at the site of delivery. In some embodiments, the reducing agent that would modify a CM would also modify the linker of the conjugated activatable antibody.
• Spacers and Cleavable Elements: In some embodiments, it can be necessary to construct the linker in such a way as to optimize the spacing between the agent and the AB of the activatable antibody. This can be accomplished by use of a linker of the general structure:
• 
  W—(CH₂)_n-Q
• wherein
  W is either —NH—CH₂— or —CH₂—;
  Q is an amino acid, peptide; and
  n is an integer from 0 to 20.
• In some embodiments, the linker can comprise a spacer element and a cleavable element. The spacer element serves to position the cleavable element away from the core of the AB such that the cleavable element is more accessible to the enzyme responsible for cleavage. Certain of the branched linkers described above can serve as spacer elements.
• Throughout this discussion, it should be understood that the attachment of linker to agent (or of spacer element to cleavable element, or cleavable element to agent) need not be particular mode of attachment or reaction. Any reaction providing a product of suitable stability and biological compatibility is acceptable.
• Serum Complement and Selection of Linkers:
• According to one method of the present disclosure, when release of an agent is desired, an AB that is an antibody of a class that can activate complement is used. The resulting conjugate retains both the ability to bind antigen and activate the complement cascade. Thus, according to this embodiment of the present disclosure, an agent is joined to one end of the cleavable linker or cleavable element and the other end of the linker group is attached to a specific site on the AB. For example, if the agent has an hydroxy group or an amino group, it can be attached to the carboxy terminus of a peptide, amino acid or other suitably chosen linker via an ester or amide bond, respectively. For example, such agents can be attached to the linker peptide via a carbodimide reaction. If the agent contains functional groups that would interfere with attachment to the linker, these interfering functional groups can be blocked before attachment and deblocked once the product conjugate or intermediate is made. The opposite or amino terminus of the linker is then used either directly or after further modification for binding to an AB that is capable of activating complement.
• Linkers (or spacer elements of linkers) can be of any desired length, one end of which can be covalently attached to specific sites on the AB of the activatable antibody. The other end of the linker or spacer element can be attached to an amino acid or peptide linker.
• Thus when these conjugates bind to antigen in the presence of complement the amide or ester bond that attaches the agent to the linker will be cleaved, resulting in release of the agent in its active form. These conjugates, when administered to a subject, will accomplish delivery and release of the agent at the target site, and are particularly effective for the in vivo delivery of pharmaceutical agents, antibiotics, antimetabolites, antiproliferative agents and the like as presented in but not limited to those in Table 5.
• Linkers for Release without Complement Activation:
• In yet another application of targeted delivery, release of the agent without complement activation is desired since activation of the complement cascade will ultimately lyse the target cell. Hence, this approach is useful when delivery and release of the agent should be accomplished without killing the target cell. Such is the goal when delivery of cell mediators such as hormones, enzymes, corticosteroids, neurotransmitters, genes or enzymes to target cells is desired. These conjugates can be prepared by attaching the agent to an AB that is not capable of activating complement via a linker that is mildly susceptible to cleavage by serum proteases. When this conjugate is administered to an individual, antigen-antibody complexes will form quickly whereas cleavage of the agent will occur slowly, thus resulting in release of the compound at the target site.
• Biochemical Cross Linkers:
• In some embodiments, the activatable antibody can be conjugated to one or more therapeutic agents using certain biochemical cross-linkers. Cross-linking reagents form molecular bridges that tie together functional groups of two different molecules. To link two different proteins in a step-wise manner, hetero-bifunctional cross-linkers can be used that eliminate unwanted homopolymer formation.
• Peptidyl linkers cleavable by lysosomal proteases are also useful, for example, Val-Cit, Val-Ala or other dipeptides. In addition, acid-labile linkers cleavable in the low-pH environment of the lysosome can be used, for example: bis-sialyl ether. Other suitable linkers include cathepsin-labile substrates, particularly those that show optimal function at an acidic pH.
• Exemplary hetero-bifunctional cross-linkers are referenced in Table 6.

• TABLE 6
  Exemplary Hetero-Bifunctional Cross Linkers
  HETERO-BIFUNCTIONAL CROSS-LINKERS

  			Spacer Arm
  			Length after
  	Reactive	Advantages and	cross-linking
  Linker	Toward	Applications	(Angstroms)
  SMPT	Primary amines	Greater stability	11.2 Å
  	Sulfhydryls
  SPDP	Primary amines	Thiolation	6.8 Å
  	Sulfhydryls	Cleavable cross-linking
  LC-	Primary amines	Extended spacer arm	15.6 Å
  SPDP	Sulfhydryls
  Sulfo-	Primary amines	Extender spacer arm	15.6 Å
  LC-	Sulfhydryls	Water-soluble
  SPDP
  SMCC	Primary amines	Stable maleimide reactive	11.6 Å
  		group
  	Sulfhydryls	Enzyme-antibody conjugation
  		Hapten-carrier protein
  		conjugation
  Sulfo-	Primary amines	Stable maleimide reactive	11.6 Å
  SMCC		group
  	Sulfhydryls	Water-soluble
  		Enzyme-antibody conjugation
  MBS	Primary amines	Enzyme-antibody conjugation	9.9 Å
  	Sulfhydryls	Hapten-carrier protein
  		conjugation
  Sulfo-	Primary amines	Water-soluble	9.9 Å
  MBS	Sulfhydryls
  SIAB	Primary amines	Enzyme-antibody conjugation	10.6 Å
  	Sulfhydryls
  Sulfo-	Primary amines	Water-soluble	10.6 Å
  SIAB	Sulfhydryls
  SMPB	Primary amines	Extended spacer arm	14.5 Å
  	Sulfhydryls	Enzyme-antibody conjugation
  Sulfo-	Primary amines	Extended spacer arm	14.5 Å
  SMPB	Sulfhydryls	Water-soluble
  EDE/	Primary amines	Hapten-Carrier conjugation	0
  Sulfo-	Carboxyl groups
  NHS
  ABH	Carbohydrates	Reacts with sugar groups	11.9 Å
  	Nonselective

• Non-Cleavable Linkers or Direct Attachment:
• In some embodiments of the disclosure, the conjugate can be designed so that the agent is delivered to the target but not released. This can be accomplished by attaching an agent to an AB either directly or via a non-cleavable linker.
• These non-cleavable linkers can include amino acids, peptides, D-amino acids or other organic compounds that can be modified to include functional groups that can subsequently be utilized in attachment to ABs by the methods described herein. A-general formula for such an organic linker could be
• 
  W—(CH₂)_n-Q
• wherein
  W is either —NH—CH₂— or —CH₂—;
  Q is an amino acid, peptide; and
  n is an integer from 0 to 20.
• Non-Cleavable Conjugates:
• In some embodiments, a compound can be attached to ABs that do not activate complement. When using ABs that are incapable of complement activation, this attachment can be accomplished using linkers that are susceptible to cleavage by activated complement or using linkers that are not susceptible to cleavage by activated complement.
• The antibodies disclosed herein can also be formulated as immunoliposomes. Liposomes containing the antibody are prepared by methods known in the art, such as described in Epstein et al., Proc. Natl. Acad. Sci. USA, 82: 3688 (1985); Hwang et al., Proc. Natl Acad. Sci. USA, 77: 4030 (1980); and U.S. Pat. Nos. 4,485,045 and 4,544,545. Liposomes with enhanced circulation time are disclosed in U.S. Pat. No. 5,013,556.
• Particularly useful liposomes can be generated by the reverse-phase evaporation method with a lipid composition comprising phosphatidylcholine, cholesterol, and PEG-derivatized phosphatidylethanolamine (PEG-PE). Liposomes are extruded through filters of defined pore size to yield liposomes with the desired diameter. Fab′ fragments of the antibody of the present disclosure can be conjugated to the liposomes as described in Martin et al., J. Biol. Chem., 257: 286-288 (1982) via a disulfide-interchange reaction.
Definitions
• Unless otherwise defined, scientific and technical terms used in connection with the present disclosure shall have the meanings that are commonly understood by those of ordinary skill in the art. The term “a” entity or “an” entity refers to one or more of that entity. For example, a compound refers to one or more compounds. As such, the terms “a”, “an”, “one or more” and “at least one” can be used interchangeably. Further, unless otherwise required by context, singular terms shall include pluralities and plural terms shall include the singular. Generally, nomenclatures utilized in connection with, and techniques of, cell and tissue culture, molecular biology, and protein and oligo- or polynucleotide chemistry and hybridization described herein are those well-known and commonly used in the art. Standard techniques are used for recombinant DNA, oligonucleotide synthesis, and tissue culture and transformation (e.g., electroporation, lipofection). Enzymatic reactions and purification techniques are performed according to manufacturer's specifications or as commonly accomplished in the art or as described herein. The foregoing techniques and procedures are generally performed according to conventional methods well known in the art and as described in various general and more specific references that are cited and discussed throughout the present specification. See e.g., Sambrook et al. Molecular Cloning: A Laboratory Manual (2d ed., Cold Spring Harbor Laboratory Press, Cold Spring Harbor, N.Y. (1989)). The nomenclatures utilized in connection with, and the laboratory procedures and techniques of, analytical chemistry, synthetic organic chemistry, and medicinal and pharmaceutical chemistry described herein are those well-known and commonly used in the art. Standard techniques are used for chemical syntheses, chemical analyses, pharmaceutical preparation, formulation, and delivery, and treatment of patients.
• As utilized in accordance with the present disclosure, the following terms, unless otherwise indicated, shall be understood to have the following meanings:
• As used herein, the term “antibody” refers to immunoglobulin molecules and antigen-binding portions of immunoglobulin (Ig) molecules, i.e., molecules that contain an antigen binding site that specifically binds (immunoreacts with) an antigen. By “specifically bind” or “immunoreacts with” or “immunospecifically bind” is meant that the antibody reacts with one or more antigenic determinants of the desired antigen and does not react with other polypeptides or binds at much lower affinity (K_d>10⁻⁶). Antibodies include, but are not limited to, polyclonal, monoclonal, chimeric, domain antibody, single chain, Fab, and F(ab′)₂ fragments, scFvs, and an Fab expression library.
• The basic antibody structural unit is known to comprise a tetramer. Each tetramer is composed of two identical pairs of polypeptide chains, each pair having one “light” (about 25 kDa) and one “heavy” chain (about 50-70 kDa). The amino-terminal portion of each chain includes a variable region of about 100 to 110 or more amino acids primarily responsible for antigen recognition. The carboxy-terminal portion of each chain defines a constant region primarily responsible for effector function. In general, antibody molecules obtained from humans relate to any of the classes IgG, IgM, IgA, IgE and IgD, which differ from one another by the nature of the heavy chain present in the molecule. Certain classes have subclasses as well, such as IgG₁, IgG₂, and others. Furthermore, in humans, the light chain can be a kappa chain or a lambda chain.
• The term “monoclonal antibody” (mAb) or “monoclonal antibody composition”, as used herein, refers to a population of antibody molecules that contain only one molecular species of antibody molecule consisting of a unique light chain gene product and a unique heavy chain gene product. In particular, the complementarity determining regions (CDRs) of the monoclonal antibody are identical in all the molecules of the population. MAbs contain an antigen binding site capable of immunoreacting with a particular epitope of the antigen characterized by a unique binding affinity for it.
• The term “antigen-binding site” or “binding portion” refers to the part of the immunoglobulin molecule that participates in antigen binding. The antigen binding site is formed by amino acid residues of the N-terminal variable (“V”) regions of the heavy (“H”) and light (“L”) chains. Three highly divergent stretches within the V regions of the heavy and light chains, referred to as “hypervariable regions,” are interposed between more conserved flanking stretches known as “framework regions,” or “FRs”. Thus, the term “FR” refers to amino acid sequences that are naturally found between, and adjacent to, hypervariable regions in immunoglobulins. In an antibody molecule, the three hypervariable regions of a light chain and the three hypervariable regions of a heavy chain are disposed relative to each other in three dimensional space to form an antigen-binding surface. The antigen-binding surface is complementary to the three-dimensional surface of a bound antigen, and the three hypervariable regions of each of the heavy and light chains are referred to as “complementarity-determining regions,” or “CDRs.” The assignment of amino acids to each domain is in accordance with the definitions of Kabat Sequences of Proteins of Immunological Interest (National Institutes of Health, Bethesda, Md. (1987 and 1991)), or Chothia & Lesk J. Mol. Biol. 196:901-917 (1987), Chothia et al. Nature 342:878-883 (1989).
• As used herein, the term “epitope” includes any protein determinant capable of specific binding to an immunoglobulin, an scFv, or a T-cell receptor. The term “epitope” includes any protein determinant capable of specific binding to an immunoglobulin or T-cell receptor. Epitopic determinants usually consist of chemically active surface groupings of molecules such as amino acids or sugar side chains and usually have specific three dimensional structural characteristics, as well as specific charge characteristics. For example, antibodies can be raised against N-terminal or C-terminal peptides of a polypeptide. An antibody is said to specifically bind an antigen when the dissociation constant is ≤1 μM; in some embodiments, ≤100 nM and in some embodiments, ≤10 nM.
• As used herein, the terms “specific binding,” “immunological binding,” and “immunological binding properties” refer to the non-covalent interactions of the type which occur between an immunoglobulin molecule and an antigen for which the immunoglobulin is specific. The strength, or affinity of immunological binding interactions can be expressed in terms of the dissociation constant (K_d) of the interaction, wherein a smaller K_d represents a greater affinity. Immunological binding properties of selected polypeptides can be quantified using methods well known in the art. One such method entails measuring the rates of antigen-binding site/antigen complex formation and dissociation, wherein those rates depend on the concentrations of the complex partners, the affinity of the interaction, and geometric parameters that equally influence the rate in both directions. Thus, both the “on rate constant” (K_on) and the “off rate constant” (K_off) can be determined by calculation of the concentrations and the actual rates of association and dissociation. (See Nature 361:186-87 (1993)). The ratio of K_off/K_on is equal to the dissociation constant K_d. (See, generally, Davies et al. (1990) Annual Rev Biochem 59:439-473). An antibody of the present disclosure is said to specifically bind to the target, when the binding constant (K_d) is ≤1 μM, in some embodiments ≤100 nM, in some embodiments 10 nM, and in some embodiments ≤100 μM to about 1 μM, as measured by assays such as radioligand binding assays or similar assays known to those skilled in the art.
• The term “isolated polynucleotide” as used herein shall mean a polynucleotide of genomic, cDNA, or synthetic origin or some combination thereof, which by virtue of its origin the “isolated polynucleotide” (1) is not associated with all or a portion of a polynucleotide in which the “isolated polynucleotide” is found in nature, (2) is operably linked to a polynucleotide which it is not linked to in nature, or (3) does not occur in nature as part of a larger sequence. Polynucleotides in accordance with the disclosure include the nucleic acid molecules encoding the heavy chain immunoglobulin molecules shown herein, and nucleic acid molecules encoding the light chain immunoglobulin molecules shown herein.
• The term “isolated protein” referred to herein means a protein of cDNA, recombinant RNA, or synthetic origin or some combination thereof, which by virtue of its origin, or source of derivation, the “isolated protein” (1) is not associated with proteins found in nature, (2) is free of other proteins from the same source, e.g., free of murine proteins, (3) is expressed by a cell from a different species, or (4) does not occur in nature.
• The term “polypeptide” is used herein as a generic term to refer to native protein, fragments, or analogs of a polypeptide sequence. Hence, native protein fragments, and analogs are species of the polypeptide genus. Polypeptides in accordance with the disclosure comprise the heavy chain immunoglobulin molecules shown herein, and the light chain immunoglobulin molecules shown herein, as well as antibody molecules formed by combinations comprising the heavy chain immunoglobulin molecules with light chain immunoglobulin molecules, such as kappa light chain immunoglobulin molecules, and vice versa, as well as fragments and analogs thereof.
• The term “naturally-occurring” as used herein as applied to an object refers to the fact that an object can be found in nature. For example, a polypeptide or polynucleotide sequence that is present in an organism (including viruses) that can be isolated from a source in nature and that has not been intentionally modified by man in the laboratory or otherwise is naturally-occurring.
• The term “operably linked” as used herein refers to positions of components so described are in a relationship permitting them to function in their intended manner. A control sequence “operably linked” to a coding sequence is ligated in such a way that expression of the coding sequence is achieved under conditions compatible with the control sequences.
• The term “control sequence” as used herein refers to polynucleotide sequences that are necessary to effect the expression and processing of coding sequences to which they are ligated. The nature of such control sequences differs depending upon the host organism in prokaryotes, such control sequences generally include promoter, ribosomal binding site, and transcription termination sequence in eukaryotes, generally, such control sequences include promoters and transcription termination sequence. The term “control sequences” is intended to include, at a minimum, all components whose presence is essential for expression and processing, and can also include additional components whose presence is advantageous, for example, leader sequences and fusion partner sequences. The term “polynucleotide” as referred to herein means nucleotides of at least 10 bases in length, either ribonucleotides or deoxynucleotides or a modified form of either type of nucleotide. The term includes single and double stranded forms of DNA.
• The term oligonucleotide referred to herein includes naturally occurring, and modified nucleotides linked together by naturally occurring, and non-naturally occurring oligonucleotide linkages. Oligonucleotides are a polynucleotide subset generally comprising a length of 200 bases or fewer. In some embodiments, oligonucleotides are 10 to 60 bases in length and in some embodiments, 12, 13, 14, 15, 16, 17, 18, 19, or 20 to 40 bases in length. Oligonucleotides are usually single stranded, e.g., for probes, although oligonucleotides can be double stranded, e.g., for use in the construction of a gene mutant. Oligonucleotides of the disclosure are either sense or antisense oligonucleotides.
• The term “naturally occurring nucleotides” referred to herein includes deoxyribonucleotides and ribonucleotides. The term “modified nucleotides” referred to herein includes nucleotides with modified or substituted sugar groups and the like. The term “oligonucleotide linkages” referred to herein includes oligonucleotide linkages such as phosphorothioate, phosphorodithioate, phosphoroselerloate, phosphorodiselenoate, phosphoroanilothioate, phoshoraniladate, phosphoronmidate, and the like. See e.g., LaPlanche et al. Nucl. Acids Res. 14:9081 (1986); Stec et al. J. Am. Chem. Soc. 106:6077 (1984), Stein et al. Nucl. Acids Res. 16:3209 (1988), Zon et al. Anti Cancer Drug Design 6:539 (1991); Zon et al. Oligonucleotides and Analogues: A Practical Approach, pp. 87-108 (F. Eckstein, Ed., Oxford University Press, Oxford England (1991)); Stec et al. U.S. Pat. No. 5,151,510; Uhlmann and Peyman Chemical Reviews 90:543 (1990). An oligonucleotide can include a label for detection, if desired.
• As used herein, the twenty conventional amino acids and their abbreviations follow conventional usage. See Immunology—A Synthesis (2nd Edition, E. S. Golub and D. R. Green, Eds., Sinauer Associates, Sunderland, Mass. (1991)). Stereoisomers (e.g., D-amino acids) of the twenty conventional amino acids, unnatural amino acids such as α-, α-disubstituted amino acids, N-alkyl amino acids, lactic acid, and other unconventional amino acids can also be suitable components for polypeptides of the present disclosure. Examples of unconventional amino acids include: 4 hydroxyproline, γ-carboxyglutamate, ε-N,N,N-trimethyllysine, ε-N-acetyllysine, O-phosphoserine, N-acetylserine, N-formylmethionine, 3-methylhistidine, 5-hydroxylysine, σ-N-methylarginine, and other similar amino acids and imino acids (e.g., 4-hydroxyproline). In the polypeptide notation used herein, the left-hand direction is the amino terminal direction and the right-hand direction is the carboxy-terminal direction, in accordance with standard usage and convention.
• Similarly, unless specified otherwise, the left-hand end of single-stranded polynucleotide sequences is the 5′ end the left-hand direction of double-stranded polynucleotide sequences is referred to as the 5′ direction. The direction of 5′ to 3′ addition of nascent RNA transcripts is referred to as the transcription direction sequence regions on the DNA strand having the same sequence as the RNA and that are 5′ to the 5′ end of the RNA transcript are referred to as “upstream sequences”, sequence regions on the DNA strand having the same sequence as the RNA and that are 3′ to the 3′ end of the RNA transcript are referred to as “downstream sequences”.
• As applied to polypeptides, the term “substantial identity” means that two peptide sequences, when optimally aligned, such as by the programs GAP or BESTFIT using default gap weights, share at least 80 percent sequence identity, in some embodiments, at least 90 percent sequence identity, in some embodiments, at least 95 percent sequence identity, and in some embodiments, at least 99 percent sequence identity.
• In some embodiments, residue positions that are not identical differ by conservative amino acid substitutions.
• As discussed herein, minor variations in the amino acid sequences of antibodies or immunoglobulin molecules are contemplated as being encompassed by the present disclosure, providing that the variations in the amino acid sequence maintain at least 75%, in some embodiments, at least 80%, 90%, 95%, and in some embodiments, 99%. In particular, conservative amino acid replacements are contemplated. Conservative replacements are those that take place within a family of amino acids that are related in their side chains. Genetically encoded amino acids are generally divided into families: (1) acidic amino acids are aspartate, glutamate; (2) basic amino acids are lysine, arginine, histidine; (3) non-polar amino acids are alanine, valine, leucine, isoleucine, proline, phenylalanine, methionine, tryptophan, and (4) uncharged polar amino acids are glycine, asparagine, glutamine, cysteine, serine, threonine, tyrosine. The hydrophilic amino acids include arginine, asparagine, aspartate, glutamine, glutamate, histidine, lysine, serine, and threonine. The hydrophobic amino acids include alanine, cysteine, isoleucine, leucine, methionine, phenylalanine, proline, tryptophan, tyrosine and valine. Other families of amino acids include (i) serine and threonine, which are the aliphatic-hydroxy family; (ii) asparagine and glutamine, which are the amide containing family; (iii) alanine, valine, leucine and isoleucine, which are the aliphatic family; and (iv) phenylalanine, tryptophan, and tyrosine, which are the aromatic family. For example, it is reasonable to expect that an isolated replacement of a leucine with an isoleucine or valine, an aspartate with a glutamate, a threonine with a serine, or a similar replacement of an amino acid with a structurally related amino acid will not have a major effect on the binding or properties of the resulting molecule, especially if the replacement does not involve an amino acid within a framework site. Whether an amino acid change results in a functional peptide can readily be determined by assaying the specific activity of the polypeptide derivative. Assays are described in detail herein. Fragments or analogs of antibodies or immunoglobulin molecules can be readily prepared by those of ordinary skill in the art. Suitable amino- and carboxy-termini of fragments or analogs occur near boundaries of functional domains. Structural and functional domains can be identified by comparison of the nucleotide and/or amino acid sequence data to public or proprietary sequence databases. In some embodiments, computerized comparison methods are used to identify sequence motifs or predicted protein conformation domains that occur in other proteins of known structure and/or function. Methods to identify protein sequences that fold into a known three-dimensional structure are known. Bowie et al. Science 253:164 (1991). Thus, the foregoing examples demonstrate that those of skill in the art can recognize sequence motifs and structural conformations that can be used to define structural and functional domains in accordance with the disclosure.
• Suitable amino acid substitutions are those that: (1) reduce susceptibility to proteolysis, (2) reduce susceptibility to oxidation, (3) alter binding affinity for forming protein complexes, (4) alter binding affinities, and (5) confer or modify other physicochemical or functional properties of such analogs. Analogs can include various muteins of a sequence other than the naturally-occurring peptide sequence. For example, single or multiple amino acid substitutions (for example, conservative amino acid substitutions) can be made in the naturally-occurring sequence (for example, in the portion of the polypeptide outside the domain(s) forming intermolecular contacts. A conservative amino acid substitution should not substantially change the structural characteristics of the parent sequence (e.g., a replacement amino acid should not tend to break a helix that occurs in the parent sequence, or disrupt other types of secondary structure that characterizes the parent sequence). Examples of art-recognized polypeptide secondary and tertiary structures are described in Proteins, Structures and Molecular Principles (Creighton, Ed., W. H. Freeman and Company, New York (1984)); Introduction to Protein Structure (C. Branden and J. Tooze, eds., Garland Publishing, New York, N.Y. (1991)); and Thornton et at. Nature 354:105 (1991).
• The term “polypeptide fragment” as used herein refers to a polypeptide that has an amino terminal and/or carboxy-terminal deletion and/or one or more internal deletion(s), but where the remaining amino acid sequence is identical to the corresponding positions in the naturally-occurring sequence deduced, for example, from a full length cDNA sequence. Fragments typically are at least 5, 6, 8 or 10 amino acids long, in some embodiments, at least 14 amino acids long, in some embodiments, at least 20 amino acids long, usually at least 50 amino acids long, and in some embodiments, at least 70 amino acids long. The term “analog” as used herein refers to polypeptides that are comprised of a segment of at least 25 amino acids that has substantial identity to a portion of a deduced amino acid sequence and that has specific binding to the target, under suitable binding conditions. Typically, polypeptide analogs comprise a conservative amino acid substitution (or addition or deletion) with respect to the naturally-occurring sequence. Analogs typically are at least 20 amino acids long, in some embodiments, at least 50 amino acids long or longer, and can often be as long as a full-length naturally-occurring polypeptide.
• The term “agent” is used herein to denote a chemical compound, a mixture of chemical compounds, a biological macromolecule, or an extract made from biological materials.
• As used herein, the terms “label” or “labeled” refers to incorporation of a detectable marker, e.g., by incorporation of a radiolabeled amino acid or attachment to a polypeptide of biotinyl moieties that can be detected by marked avidin (e.g., streptavidin containing a fluorescent marker or enzymatic activity that can be detected by optical or calorimetric methods). In certain situations, the label or marker can also be therapeutic. Various methods of labeling polypeptides and glycoproteins are known in the art and can be used. Examples of labels for polypeptides include, but are not limited to, the following: radioisotopes ³H, ¹⁴C, ¹⁵N, ³⁵S, ⁹⁰Y, ⁹⁹Tc, ¹¹¹In, ¹²⁵I, ¹³¹I), or radionuclides (e.g., fluorescent labels (e.g., FITC, rhodamine, lanthanide phosphors), enzymatic labels (e.g., horseradish peroxidase, p-galactosidase, luciferase, alkaline phosphatase), chemiluminescent, biotinyl groups, predetermined polypeptide epitopes recognized by a secondary reporter (e.g., leucine zipper pair sequences, binding sites for secondary antibodies, metal binding domains, epitope tags). In some embodiments, labels are attached by spacer arms of various lengths to reduce potential steric hindrance. The term “pharmaceutical agent or drug” as used herein refers to a chemical compound or composition capable of inducing a desired therapeutic effect when properly administered to a patient.
• Other chemistry terms herein are used according to conventional usage in the art, as exemplified by The McGraw-Hill Dictionary of Chemical Terms (Parker, S., Ed., McGraw-Hill, San Francisco (1985)).
• As used herein, “substantially pure” means an object species is the predominant species present (i.e., on a molar basis it is more abundant than any other individual species in the composition), and in some embodiments, a substantially purified fraction is a composition wherein the object species comprises at least about 50 percent (on a molar basis) of all macromolecular species present.
• Generally, a substantially pure composition will comprise more than about 80 percent of all macromolecular species present in the composition, in some embodiments, more than about 85%, 90%, 95%, and 99%. In some embodiments, the object species is purified to essential homogeneity (contaminant species cannot be detected in the composition by conventional detection methods) wherein the composition consists essentially of a single macromolecular species.
• The term patient includes human and veterinary subjects.
• Antibodies and/or activatable antibodies of the disclosure specifically bind a given target, e.g., a human target protein such as human PD-1. Also included in the disclosure are antibodies and/or activatable antibodies that bind to the same epitope as the antibodies and/or activatable antibodies described herein. Also included in the disclosure are antibodies and/or antibodies activatable antibodies that compete with an anti-PD-1 antibody and/or an anti-PD-1 activatable antibody described herein for binding to PD-1, e.g., human PD-1. Also included in the disclosure are antibodies and/or antibodies activatable antibodies that cross-compete with an anti-PD-1 antibody and/or an anti-PD-1 activatable antibody described herein for binding to PD-1, e.g., human PD-1.
• Those skilled in the art will recognize that it is possible to determine, without undue experimentation, if a monoclonal antibody (e.g., a murine monoclonal or humanized antibody) has the same specificity as a monoclonal antibody used in the methods described herein by ascertaining whether the former prevents the latter from binding to the target. If the monoclonal antibody being tested competes with the monoclonal antibody of the disclosure, as shown by a decrease in binding by the monoclonal antibody of the disclosure, then the two monoclonal antibodies bind to the same, or a closely related, epitope. An alternative method for determining whether a monoclonal antibody has the specificity of a monoclonal antibody of the disclosure is to pre-incubate the monoclonal antibody of the disclosure with the target and then add the monoclonal antibody being tested to determine if the monoclonal antibody being tested is inhibited in its ability to bind the target. If the monoclonal antibody being tested is inhibited then, in all likelihood, it has the same, or functionally equivalent, epitopic specificity as the monoclonal antibody of the disclosure.
• Multispecific Activatable Antibodies
• The disclosure also provides multispecific anti-PD-1 activatable antibodies. The multispecific activatable antibodies provided herein are multispecific antibodies that recognize PD-1 and at least one or more different antigens or epitopes and that include at least one masking moiety (MM) linked to at least one antigen- or epitope-binding domain of the multispecific antibody such that coupling of the MM reduces the ability of the antigen- or epitope-binding domain to bind its target. In some embodiments, the MM is coupled to the antigen- or epitope-binding domain of the multispecific antibody via a cleavable moiety (CM) that functions as a substrate for at least one protease. The activatable multispecific antibodies provided herein are stable in circulation, activated at intended sites of therapy and/or diagnosis but not in normal, i.e., healthy tissue, and, when activated, exhibit binding to a target that is at least comparable to the corresponding, unmodified multispecific antibody.
• In some embodiments, the multispecific activatable antibodies are designed to engage immune effector cells, also referred to herein as immune-effector cell engaging multispecific activatable antibodies. In some embodiments, the multispecific activatable antibodies are designed to engage leukocytes, also referred to herein as leukocyte engaging multispecific activatable antibodies. In some embodiments, the multispecific activatable antibodies are designed to engage T cells, also referred to herein as T-cell engaging multispecific activatable antibodies. In some embodiments, the multispecific activatable antibodies engage a surface antigen on a leukocyte, such as on a T cell, on a natural killer (NK) cell, on a myeloid mononuclear cell, on a macrophage, and/or on another immune effector cell. In some embodiments, the immune effector cell is a leukocyte. In some embodiments, the immune effector cell is a T cell. In some embodiments, the immune effector cell is a NK cell. In some embodiments, the immune effector cell is a mononuclear cell, such as a myeloid mononuclear cell. In some embodiments, the multispecific activatable antibodies are designed to bind or otherwise interact with more than one target and/or more than one epitope, also referred to herein as multi-antigen targeting activatable antibodies. As used herein, the terms “target” and “antigen” are used interchangeably.
• In some embodiments, immune effector cell engaging multispecific activatable antibodies of the disclosure include a targeting antibody or antigen-binding fragment thereof that binds PD-1 and an immune effector cell engaging antibody or antigen-binding portion thereof, where at least one of the targeting antibody or antigen-binding fragment thereof and/or the immune effector cell engaging antibody or antigen-binding portion thereof is masked. In some embodiments, the immune effector cell engaging antibody or antigen binding fragment thereof includes a first antibody or antigen-binding fragment thereof (AB1) that binds a first, immune effector cell engaging target, where the AB1 is attached to a masking moiety (MM1) such that coupling of the MM1 reduces the ability of the AB1 to bind the first target. In some embodiments, the targeting antibody or antigen-binding fragment thereof includes a second antibody or fragment thereof that includes a second antibody or antigen-binding fragment thereof (AB2) that binds PD-1, where the AB2 is attached to a masking moiety (MM2) such that coupling of the MM2 reduces the ability of the AB2 to bind PD-1. In some embodiments, the immune effector cell engaging antibody or antigen binding fragment thereof includes a first antibody or antigen-binding fragment thereof (AB1) that binds a first, immune effector cell engaging target, where the AB1 is attached to a masking moiety (MM1) such that coupling of the MIMI reduces the ability of the AB1 to bind the first target, and the targeting antibody or antigen-binding fragment thereof includes a second antibody or fragment thereof that includes a second antibody or antigen-binding fragment thereof (AB2) that binds PD-1, where the AB2 is attached to a masking moiety (MM2) such that coupling of the MM2 reduces the ability of the AB2 to bind PD-1. In some embodiments, the non-immune effector cell engaging antibody is a cancer targeting antibody. In some embodiments the non-immune cell effector antibody is an IgG. In some embodiments the immune effector cell engaging antibody is a scFv. In some embodiments the PD-1-targeting antibody (e.g., non-immune cell effector antibody) is an IgG and the immune effector cell engaging antibody is a scFv. In some embodiments, the immune effector cell is a leukocyte. In some embodiments, the immune effector cell is a T cell. In some embodiments, the immune effector cell is a NK cell. In some embodiments, the immune effector cell is a myeloid mononuclear cell.
• In some embodiments, T-cell engaging multispecific activatable antibodies of the disclosure include a PD-1-targeting antibody or antigen-binding fragment thereof and a T-cell engaging antibody or antigen-binding portion thereof, where at least one of the PD-1-targeting antibody or antigen-binding fragment thereof and/or the T-cell engaging antibody or antigen-binding portion thereof is masked. In some embodiments, the T-cell engaging antibody or antigen binding fragment thereof includes a first antibody or antigen-binding fragment thereof (AB1) that binds a first, T-cell engaging target, where the AB1 is attached to a masking moiety (MM1) such that coupling of the MM1 reduces the ability of the AB1 to bind the first target. In some embodiments, the targeting antibody or antigen-binding fragment thereof includes a second antibody or fragment thereof that includes a second antibody or antigen-binding fragment thereof (AB2) that binds PD-1, where the AB2 is attached to a masking moiety (MM2) such that coupling of the MM2 reduces the ability of the AB2 to bind PD-1. In some embodiments, the T-cell engaging antibody or antigen binding fragment thereof includes a first antibody or antigen-binding fragment thereof (AB1) that binds a first, T-cell engaging target, where the AB1 is attached to a masking moiety (MM1) such that coupling of the MM1 reduces the ability of the AB1 to bind the first target, and the targeting antibody or antigen-binding fragment thereof includes a second antibody or fragment thereof that includes a second antibody or antigen-binding fragment thereof (AB2) that binds PD-1, where the AB2 is attached to a masking moiety (MM2) such that coupling of the MM2 reduces the ability of the AB2 to bind PD-1.
• In some embodiments of an immune effector cell engaging multispecific activatable antibody, one antigen is PD-1, and another antigen is typically a stimulatory or inhibitory receptor present on the surface of a T-cell, natural killer (NK) cell, myeloid mononuclear cell, macrophage, and/or other immune effector cell, such as, but not limited to, B7-H4, BTLA, CD3, CD4, CD8, CD16a, CD25, CD27, CD28, CD32, CD56, CD137, CTLA-4, GITR, HVEM, ICOS, LAG3, NKG2D, OX40, TIGIT, TIM3, or VISTA. In some embodiments, the antigen is a stimulatory receptor present on the surface of a T cell or NK cell; examples of such stimulatory receptors include, but are not limited to, CD3, CD27, CD28, CD137 (also referred to as 4-1BB), GITR, HVEM, ICOS, NKG2D, and OX40. In some embodiments, the antigen is an inhibitory receptor present on the surface of a T-cell; examples of such inhibitory receptors include, but are not limited to, BTLA, CTLA-4, LAG3, TIGIT, TIM3, and NK-expressed KIRs. The antibody domain conferring specificity to the T-cell surface antigen can also be substituted by a ligand or ligand domain that binds to a T-cell receptor, a NK-cell receptor, a macrophage receptor, and/or other immune effector cell receptor, such as, but not limited to, B7-1, B7-2, B7H3, PDL1, PDL2, or TNFSF9.
• In some embodiments, the T-cell engaging multispecific activatable antibody includes an anti-CD3 epsilon (CD3ε, also referred to herein as CD3e and CD3) scFv and a targeting antibody or antigen-binding fragment thereof, where at least one of the anti-CD3ε scFv and/or the targeting antibody or antigen-binding portion thereof is masked. In some embodiments, the CD3ε scFv includes a first antibody or antigen-binding fragment thereof (AB1) that binds CD3ε, where the AB1 is attached to a masking moiety (MM1) such that coupling of the MM1 reduces the ability of the AB1 to bind CD3ε. In some embodiments, the targeting antibody or antigen-binding fragment thereof includes a second antibody or fragment thereof that includes a second antibody or antigen-binding fragment thereof (AB2) that binds PD-1, where the AB2 is attached to a masking moiety (MM2) such that coupling of the MM2 reduces the ability of the AB2 to bind PD-1. In some embodiments, the CD3ε scFv includes a first antibody or antigen-binding fragment thereof (AB1) that binds CD3ε, where the AB1 is attached to a masking moiety (MM1) such that coupling of the MM1 reduces the ability of the AB1 to bind CD3ε, and the targeting antibody or antigen-binding fragment thereof includes a second antibody or fragment thereof that includes a second antibody or antigen-binding fragment thereof (AB2) that binds PD-1, where the AB2 is attached to a masking moiety (MM2) such that coupling of the MM2 reduces the ability of the AB2 to bind PD-1.
• In some embodiments, the multi-antigen targeting antibodies and/or multi-antigen targeting activatable antibodies include at least a first antibody or antigen-binding fragment thereof that binds a first target and/or first epitope and a second antibody or antigen-binding fragment thereof that binds a second target and/or a second epitope. In some embodiments, the multi-antigen targeting antibodies and/or multi-antigen targeting activatable antibodies bind two or more different targets. In some embodiments, the multi-antigen targeting antibodies and/or multi-antigen targeting activatable antibodies bind two or more different epitopes on the same target. In some embodiments, the multi-antigen targeting antibodies and/or multi-antigen targeting activatable antibodies bind a combination of two or more different targets and two or more different epitopes on the same target.
• In some embodiments, a multispecific activatable antibody comprising an IgG has the IgG variable domains masked. In some embodiments, a multispecific activatable antibody comprising a scFv has the scFv domains masked. In some embodiments, a multispecific activatable antibody has both IgG variable domains and scFv domains, where at least one of the IgG variable domains is coupled to a masking moiety. In some embodiments, a multispecific activatable antibody has both IgG variable domains and scFv domains, where at least one of the scFv domains is coupled to a masking moiety. In some embodiments, a multispecific activatable antibody has both IgG variable domains and scFv domains, where at least one of the IgG variable domains is coupled to a masking moiety and at least one of the scFv domains is coupled to a masking moiety. In some embodiments, a multispecific activatable antibody has both IgG variable domains and scFv domains, where each of the IgG variable domains and the scFv domains is coupled to its own masking moiety. In some embodiments, one antibody domain of a multispecific activatable antibody has specificity for a target antigen and another antibody domain has specificity for a T-cell surface antigen. In some embodiments, one antibody domain of a multispecific activatable antibody has specificity for a target antigen and another antibody domain has specificity for another target antigen. In some embodiments, one antibody domain of a multispecific activatable antibody has specificity for an epitope of a target antigen and another antibody domain has specificity for another epitope of the target antigen.
• In a multispecific activatable antibody, a scFv can be fused to the carboxyl terminus of the heavy chain of an IgG activatable antibody, to the carboxyl terminus of the light chain of an IgG activatable antibody, or to the carboxyl termini of both the heavy and light chains of an IgG activatable antibody. In a multispecific activatable antibody, a scFv can be fused to the amino terminus of the heavy chain of an IgG activatable antibody, to the amino terminus of the light chain of an IgG activatable antibody, or to the amino termini of both the heavy and light chains of an IgG activatable antibody. In a multispecific activatable antibody, a scFv can be fused to any combination of one or more carboxyl termini and one or more amino termini of an IgG activatable antibody. In some embodiments, a masking moiety (MM) linked to a cleavable moiety (CM) is attached to and masks an antigen binding domain of the IgG. In some embodiments, a masking moiety (MM) linked to a cleavable moiety (CM) is attached to and masks an antigen binding domain of at least one scFv. In some embodiments, a masking moiety (MM) linked to a cleavable moiety (CM) is attached to and masks an antigen binding domain of an IgG and a masking moiety (MM) linked to a cleavable moiety (CM) is attached to and masks an antigen binding domain of at least one scFv.
• The disclosure provides examples of multispecific activatable antibody structures which include, but are not limited to, the following: (VL-CL)₂:(VH-CH1-CH2-CH3-L4-VH*-L3-VL*-L2-CM-L1-MM)₂; (VL-CL)₂:(VH-CH1-CH2-CH3-L4-VL*-L3-VH*-L2-CM-L1-MM)₂; (MM-L1-CM-L2-VL-CL)₂:(VH-CH1-CH2-CH3-L4-VH*-L3-VL*)₂; (MM-L1-CM-L2-VL-CL)₂:(VH-CH1-CH2-CH3-L4-VL*-L3-VH*)₂; (VL-CL)₂:(MM-L1-CM-L2-VL*-L3-VH*-L4-VH-CH1-CH2-CH3)₂; (VL-CL)₂:(MM-L1-CM-L2-VH*-L3-VL*-L4-VH-CH1-CH2-CH3)₂; (MM-L1-CM-L2-VL-CL)₂:(VL*-L3-VH*-L4-VH-CH1-CH2-CH3)₂; (MM-L1-CM-L2-VL-CL)₂:(VH*-L3-VL*-L4-VH-CH1-CH2-CH3)₂; (VL-CL-L4-VH*-L3-VL*-L2-CM-L1-MM)₂: (VH-CH1-CH2-CH3)₂; (VL-CL-L4-VL*-L3-VH*-L2-CM-L1-MM)₂: (VH-CH1-CH2-CH3)₂; (MM-L1-CM-L2-VL*-L3-VH*-L4-VL-CL)₂:(VH-CH1-CH2-CH3)₂; (MM-L1-CM-L2-VH*-L3-VL*-L4-VL-CL)₂:(VH-CH1-CH2-CH3)₂; (VL-CL-L4-VH*-L3-VL*-L2-CM-L1-MM)₂: (MM-L1-CM-L2-VL*-L3-VH*-L4-VH-CH1-CH2-CH3)₂; (VL-CL-L4-VH*-L3-VL*-L2-CM-L1-MM)₂: (MM-L1-CM-L2-VH*-L3-VL*-L4-VH-CH1-CH2-CH3)₂; (VL-CL-L4-VL*-L3-VH*-L2-CM-L1-MM)₂: (MM-L1-CM-L2-VL*-L3-VH*-L4-VH-CH1-CH2-CH3)₂; (VL-CL-L4-VL*-L3-VH*-L2-CM-L1-MM)₂: (MM-L1-CM-L2-VH*-L3-VL*-L4-VH-CH1-CH2-CH3)₂; (VL-CL-L4-VH*-L3-VL*)₂: (MM-L1-CM-L2-VL*-L3-VH*-L4-VH-CH1-CH2-CH3)₂; (VL-CL-L4-VH*-L3-VL*)₂: (MM-L1-CM-L2-VH*-L3-VL*-L4-VH-CH1-CH2-CH3)₂; (VL-CL-L4-VL*-L3-VH*)₂: (MM-L1-CM-L2-VL*-L3-VH*-L4-VH-CH1-CH2-CH3)₂; (VL-CL-L4-VL*-L3-VH*)₂: (MM-L1-CM-L2-VH*-L3-VL*-L4-VH-CH1-CH2-CH3)₂; (VL-CL-L4-VH*-L3-VL*-L2-CM-L1-MM)₂: (VL*-L3-VH*-L4-VH-CH1-CH2-CH3)₂; (VL-CL-L4-VH*-L3-VL*-L2-CM-L1-MM)₂: (VH*-L3-VL*-L4-VH-CH1-CH2-CH3)₂; (VL-CL-L4-VL*-L3-VH*-L2-CM-L1-MM)₂: (VL*-L3-VH*-L4-VH-CH1-CH2-CH3)₂; or (VL-CL-L4-VL*-L3-VH*-L2-CM-L1-MM)₂: (VH*-L3-VL*-L4-VH-CH1-CH2-CH3)₂, wherein: VL and VH represent the light and heavy variable domains of the first specificity, contained in the IgG; VL* and VH* represent the variable domains of the second specificity, contained in the scFv; L1 is a linker peptide connecting the masking moiety (MM) and the cleavable moiety (CM); L2 is a linker peptide connecting the cleavable moiety (CM), and the antibody; L3 is a linker peptide connecting the variable domains of the scFv; L4 is a linker peptide connecting the antibody of the first specificity to the antibody of the second specificity; CL is the light-chain constant domain; and CH1, CH2, CH3 are the heavy chain constant domains. The first and second specificities can be toward any antigen or epitope.
• In some embodiments of a T-cell engaging multispecific activatable antibody, one antigen is PD-1, and another antigen is typically a stimulatory (also referred to herein as activating) or inhibitory receptor present on the surface of a T-cell, natural killer (NK) cell, myeloid mononuclear cell, macrophage, and/or other immune effector cell, such as, but not limited to, B7-H4, BTLA, CD3, CD4, CD8, CD16a, CD25, CD27, CD28, CD32, CD56, CD137 (also referred to as TNFRSF9), CTLA-4, GITR, HVEM, ICOS, LAG3, NKG2D, OX40, PD-1, TIGIT, TIM3, or VISTA. The antibody domain conferring specificity to the T-cell surface antigen can also be substituted by a ligand or ligand domain that binds to a T-cell receptor, a NK-cell receptor, a macrophage receptor, and/or other immune effector cell receptor.
• In some embodiments, the targeting antibody is an anti-PD-1 antibody disclosed herein. In some embodiments, the targeting antibody can be in the form an activatable antibody. In some embodiments, the scFv(s) can be in the form of a Pro-scFv (see, e.g., WO 2009/025846, WO 2010/081173).
• In some embodiments, the scFv is specific for binding CDR, and comprises or is derived from an antibody or fragment thereof that binds CD3ε, e.g., CH2527, FN18, H2C, OKT3, 2C11, UCHT1, or V9. In some embodiments, the scFv is specific for binding CTLA-4 (also referred to herein as CTLA and CTLA4).
• In some embodiments, the anti-CTLA-4 scFv includes the amino acid sequence:

• (SEQ ID NO: 585)

  GGGSGGGGSGSGGGSGGGGSGGGEIVLTQSPGTLSLSPGERATLSCRASQ

  SVSSSYLAWYQQKPGQAPRLLIYGASSRATGIPDRFSGSGSGTDFTLTIS

  RLEPEDFAVYYCQQYGSSPLTFGGGTKVEIKRSGGSTITSYNVYYTKLSS

  SGTQVQLVQTGGGVVQPGRSLRLSCAASGSTFSSYAMSWVRQAPGKGLEW

  VSAISGSGGSTYYADSVKGRFTISRDNSKNTLYLQMNSLRAEDTAVYYCA

  TNSLYWYFDLWGRGTLVTVSSAS

• In some embodiments, the anti-CTLA-4 scFv includes the amino acid sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to the amino acid sequence of SEQ ID NO: 585.
• In some embodiments, the anti-CDR scFv includes the amino acid sequence:

• (SEQ ID NO: 586)

  GGGSGGGGSGSGGGSGGGGSGGGQVQLQQSGAELARPGASVKMSCKASGY

  TFTRYTMHWVKQRPGQGLEWIGYINPSRGYTNYNQKFKDKATLTTDKSSS

  TAYMQLSSLTSEDSAVYYCARYYDDHYCLDYWGQGTTLTVSSGGGGSG

  GGGSGGGGSQIVLTQSPAIMSASPGEKVTMTCSASSSVSYMNWYQQKS

  GTSPKRWIYDTSKLASGVPAHFRGSGSGTSYSLTISGMEAEDAATYYCQ

  QWSSNPFTFGSGTKLEINR

• In some embodiments, the anti-CDR scFv includes the amino acid sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more identical to the amino acid sequence of SEQ ID NO: 586.
• In some embodiments, the scFv is specific for binding one or more T-cells, one or more NK-cells and/or one or more macrophages. In some embodiments, the scFv is specific for binding a target selected from the group consisting of B7-H4, BTLA, CD3, CD4, CD8, CD16a, CD25, CD27, CD28, CD32, CD56, CD137, CTLA-4, GITR, HVEM, ICOS, LAG3, NKG2D, OX40, TIGIT, TIM3, or VISTA.
• In some embodiments, the multispecific activatable antibody also includes an agent conjugated to the AB. In some embodiments, the agent is a therapeutic agent. In some embodiments, the agent is conjugated to the multispecific activatable antibody via a linker. In some embodiments, the agent is conjugated to the AB via a cleavable linker. In some embodiments, the linker is a non-cleavable linker.
• In some embodiments, the multispecific activatable antibody also includes a detectable moiety. In some embodiments, the detectable moiety is a diagnostic agent.
• In some embodiments, the multispecific activatable antibody naturally contains one or more disulfide bonds. In some embodiments, the multispecific activatable antibody can be engineered to include one or more disulfide bonds.
• The disclosure also provides an isolated nucleic acid molecule encoding a multispecific activatable antibody described herein, as well as vectors that include these isolated nucleic acid sequences. The disclosure provides methods of producing a multispecific activatable antibody by culturing a cell under conditions that lead to expression of the activatable antibody, wherein the cell comprises such a nucleic acid molecule. In some embodiments, the cell comprises such a vector.
• The disclosure also provides a method of manufacturing multispecific activatable antibodies of the disclosure by (a) culturing a cell comprising a nucleic acid construct that encodes the multispecific activatable antibody under conditions that lead to expression of the multispecific activatable, and (b) recovering the multispecific activatable antibody. Suitable AB, MM, and/or CM include any of the AB, MM, and/or CM disclosed herein.
• The disclosure also provides multispecific activatable antibodies and/or multispecific activatable antibody compositions that include at least a first antibody or antigen-binding fragment thereof (AB1) that specifically binds a first target or first epitope and a second antibody or antigen-biding fragment thereof (AB2) that binds a second target or a second epitope, where at least AB1 is coupled or otherwise attached to a masking moiety (MM1), such that coupling of the MM1 reduces the ability of AB1 to bind its target. In some embodiments, the MM1 is coupled to AB1 via a first cleavable moiety (CM1) sequence that includes a substrate for a protease, for example, a protease that is co-localized with the target of AB1 at a treatment site or a diagnostic site in a subject. The multispecific activatable antibodies provided herein are stable in circulation, activated at intended sites of therapy and/or diagnosis but not in normal, i.e., healthy tissue, and, when activated, exhibit binding to the target of AB1 that is at least comparable to the corresponding, unmodified multispecific antibody. Suitable AB, MM, and/or CM include any of the AB, MM, and/or CM disclosed herein.
• The disclosure also provides compositions and methods that include a multispecific activatable antibody that includes at least a first antibody or antibody fragment (AB1) that specifically binds a target and a second antibody or antibody fragment (AB2), where at least the first AB in the multispecific activatable antibody is coupled to a masking moiety (MM1) that decreases the ability of AB1 to bind its target. In some embodiments, each AB is coupled to a MM that decreases the ability of its corresponding AB to each target. For example, in bispecific activatable antibody embodiments, AB1 is coupled to a first masking moiety (MM1) that decreases the ability of AB1 to bind its target, and AB2 is coupled to a second masking moiety (MM2) that decreases the ability of AB2 to bind its target. In some embodiments, the multispecific activatable antibody comprises more than two AB regions; in such embodiments, AB1 is coupled to a first masking moiety (MM1) that decreases the ability of AB1 to bind its target, AB2 is coupled to a second masking moiety (MM2) that decreases the ability of AB2 to bind its target, AB3 is coupled to a third masking moiety (MM3) that decreases the ability of AB3 to bind its target, and so on for each AB in the multispecific activatable antibody. Suitable AB, MM, and/or CM include any of the AB, MM, and/or CM disclosed herein.
• In some embodiments, the multispecific activatable antibody further includes at least one cleavable moiety (CM) that is a substrate for a protease, where the CM links a MM to an AB. For example, in some embodiments, the multispecific activatable antibody includes at least a first antibody or antibody fragment (AB1) that specifically binds a target and a second antibody or antibody fragment (AB2), where at least the first AB in the multispecific activatable antibody is coupled via a first cleavable moiety (CM1) to a masking moiety (MM1) that decreases the ability of AB1 to bind its target. In some bispecific activatable antibody embodiments, AB1 is coupled via CM1 to MM1, and AB2 is coupled via a second cleavable moiety (CM2) to a second masking moiety (MM2) that decreases the ability of AB2 to bind its target. In some embodiments, the multispecific activatable antibody comprises more than two AB regions; in some of these embodiments, AB1 is coupled via CM1 to MM1, AB2 is coupled via CM2 to MM2, and AB3 is coupled via a third cleavable moiety (CM3) to a third masking moiety (MM3) that decreases the ability of AB3 to bind its target, and so on for each AB in the multispecific activatable antibody. Suitable AB, MM, and/or CM include any of the AB, MM, and/or CM disclosed herein.
• Activatable Antibodies Having Non-Binding Steric Moieties or Binding Partners for Non-Binding Steric Moieties
• The disclosure also provides activatable antibodies that include non-binding steric moieties (NB) or binding partners (BP) for non-binding steric moieties, where the BP recruits or otherwise attracts the NB to the activatable antibody. The activatable antibodies provided herein include, for example, an activatable antibody that includes a non-binding steric moiety (NB), a cleavable linker (CL) and antibody or antibody fragment (AB) that binds a target; an activatable antibody that includes a binding partner for a non-binding steric moiety (BP), a CL and an AB; and an activatable antibody that includes a BP to which an NB has been recruited, a CL and an AB that binds the target. Activatable antibodies in which the NB is covalently linked to the CL and AB of the activatable antibody or is associated by interaction with a BP that is covalently linked to the CL and AB of the activatable antibody are referred to herein as “NB-containing activatable antibodies.” By activatable or switchable is meant that the activatable antibody exhibits a first level of binding to a target when the activatable antibody is in an inhibited, masked or uncleaved state (i.e., a first conformation), and a second level of binding to the target when the activatable antibody is in an uninhibited, unmasked and/or cleaved state (i.e., a second conformation, i.e., activated antibody), where the second level of target binding is greater than the first level of target binding. The activatable antibody compositions can exhibit increased bioavailability and more favorable biodistribution compared to conventional antibody therapeutics.
• In some embodiments, activatable antibodies provide for reduced toxicity and/or adverse side effects that could otherwise result from binding of the at non-treatment sites and/or non-diagnostic sites if the AB were not masked or otherwise inhibited from binding to such a site.
• Anti-PD-1 activatable antibodies that include a non-binding steric moiety (NB) can be made using the methods set forth in PCT Publication No. WO 2013/192546, the contents of which are hereby incorporated by reference in their entirety.
• Use of Antibodies and Activatable Antibodies
• It will be appreciated that administration of therapeutic entities in accordance with the disclosure will be administered with suitable carriers, excipients, and other agents that are incorporated into formulations to provide improved transfer, delivery, tolerance, and the like. A multitude of appropriate formulations can be found in the formulary known to all pharmaceutical chemists: Remington's Pharmaceutical Sciences (15th ed, Mack Publishing Company, Easton, Pa. (1975)), particularly Chapter 87 by Blaug, Seymour, therein. These formulations include, for example, powders, pastes, ointments, jellies, waxes, oils, lipids, lipid (cationic or anionic) containing vesicles (such as Lipofectin™), DNA conjugates, anhydrous absorption pastes, oil-in-water and water-in-oil emulsions, emulsions carbowax (polyethylene glycols of various molecular weights), semi-solid gels, and semi-solid mixtures containing carbowax. Any of the foregoing mixtures can be appropriate in treatments and therapies in accordance with the present disclosure, provided that the active ingredient in the formulation is not inactivated by the formulation and the formulation is physiologically compatible and tolerable with the route of administration. See also Baldrick P. “Pharmaceutical excipient development: the need for preclinical guidance.” Regul. Toxicol Pharmacol. 32(2):210-8 (2000), Wang W. “Lyophilization and development of solid protein pharmaceuticals.” Int. J. Pharm. 203(1-2):1-60 (2000), Charman W N “Lipids, lipophilic drugs, and oral drug delivery-some emerging concepts.” J Pharm Sci. 89(8):967-78 (2000), Powell et al. “Compendium of excipients for parenteral formulations” PDA J Pharm Sci Technol. 52:238-311 (1998) and the citations therein for additional information related to formulations, excipients and carriers well known to pharmaceutical chemists.
• Therapeutic formulations of the disclosure, which include an anti-PD-1 antibody and/or activatable anti-PD-1 antibody, such as by way of non-limiting example, an antibody and/or an activatable antibody, are used to prevent, treat or otherwise ameliorate a disease or disorder associated with aberrant target expression and/or activity. For example, therapeutic formulations of the disclosure, which include an antibody and/or an activatable antibody, are used to treat or otherwise ameliorate a cancer or other neoplastic condition, inflammation, an inflammatory disorder, and/or an autoimmune disease. In some embodiments, the cancer is a solid tumor or a hematologic malignancy where the target is expressed. In some embodiments, the cancer is a solid tumor where the target is expressed. In some embodiments, the cancer is a hematologic malignancy where the target is expressed. In some embodiments, the target is expressed on parenchyma (e.g., in cancer, the portion of an organ or tissue that often carries out function(s) of the organ or tissue). In some embodiments, the target is expressed on a cell, tissue, or organ. In some embodiments, the target is expressed on stroma (i.e., the connective supportive framework of a cell, tissue, or organ). In some embodiments, the target is expressed on an osteoblast. In some embodiments, the target is expressed on the endothelium (vasculature). In some embodiments, the target is expressed on a cancer stem cell.
• Efficaciousness of prevention, amelioration or treatment is determined in association with any known method for diagnosing or treating the disease or disorder associated with target expression and/or activity, such as, for example, aberrant target expression and/or activity. Prolonging the survival of a subject or otherwise delaying the progression of the disease or disorder associated with target expression and/or activity, e.g., aberrant target expression and/or activity, in a subject indicates that the antibody and/or activatable antibody confers a clinical benefit.
• An antibody and/or an activatable antibody can be administered in the form of pharmaceutical compositions. Principles and considerations involved in preparing such compositions, as well as guidance in the choice of components are provided, for example, in Remington: The Science And Practice Of Pharmacy 19th ed. (Alfonso R. Gennaro, et al., editors) Mack Pub. Co., Easton, Pa.: 1995; Drug Absorption Enhancement: Concepts, Possibilities, Limitations, And Trends, Harwood Academic Publishers, Langhorne, Pa., 1994; and Peptide And Protein Drug Delivery (Advances In Parenteral Sciences, Vol. 4), 1991, M. Dekker, New York.
• In some embodiments where antibody fragments are used, the smallest fragment that specifically binds to the binding domain of the target protein is selected. For example, based upon the variable-region sequences of an antibody, peptide molecules can be designed that retain the ability to bind the target protein sequence. Such peptides can be synthesized chemically and/or produced by recombinant DNA technology. (See, e.g., Marasco et al., Proc. Natl. Acad. Sci. USA, 90: 7889-7893 (1993)). The formulation can also contain more than one active compounds as necessary for the particular indication being treated, for example, in some embodiments, those with complementary activities that do not adversely affect each other. In some embodiments, or in addition, the composition can comprise an agent that enhances its function, such as, for example, a cytotoxic agent, cytokine, chemotherapeutic agent, or growth-inhibitory agent. Such molecules are suitably present in combination in amounts that are effective for the purpose intended.
• The active ingredients can also be entrapped in microcapsules prepared, for example, by coacervation techniques or by interfacial polymerization, for example, hydroxymethylcellulose or gelatin-microcapsules and poly-(methylmethacrylate) microcapsules, respectively, in colloidal drug delivery systems (for example, liposomes, albumin microspheres, microemulsions, nano-particles, and nanocapsules) or in macroemulsions.
• The formulations to be used for in vivo administration must be sterile. This is readily accomplished by filtration through sterile filtration membranes.
• Sustained-release preparations can be prepared. Suitable examples of sustained-release preparations include semipermeable matrices of solid hydrophobic polymers containing the antibody, which matrices are in the form of shaped articles, e.g., films, or microcapsules. Examples of sustained-release matrices include polyesters, hydrogels (for example, poly(2-hydroxyethyl-methacrylate), or poly(vinylalcohol)), polylactides (U.S. Pat. No. 3,773,919), copolymers of L-glutamic acid and γ ethyl-L-glutamate, non-degradable ethylene-vinyl acetate, degradable lactic acid-glycolic acid copolymers such as the LUPRON DEPOT™ (injectable microspheres composed of lactic acid-glycolic acid copolymer and leuprolide acetate), and poly-D-(−)-3-hydroxybutyric acid. While polymers such as ethylene-vinyl acetate and lactic acid-glycolic acid enable release of molecules for over 100 days, certain hydrogels release proteins for shorter time periods.
• In some embodiments, the antibody and/or activatable antibody contains a detectable label. An intact antibody, or a fragment thereof (e.g., Fab, scFv, or F(ab)₂) is used. The term “labeled”, with regard to the probe or antibody, is intended to encompass direct labeling of the probe or antibody by coupling (i.e., physically linking) a detectable substance to the probe or antibody, as well as indirect labeling of the probe or antibody by reactivity with another reagent that is directly labeled. Examples of indirect labeling include detection of a primary antibody using a fluorescently-labeled secondary antibody and end-labeling of a DNA probe with biotin such that it can be detected with fluorescently-labeled streptavidin. The term “biological sample” is intended to include tissues, cells and biological fluids isolated from a subject, as well as tissues, cells and fluids present within a subject. Included within the usage of the term “biological sample”, therefore, is blood and a fraction or component of blood including blood serum, blood plasma, or lymph. That is, the detection method of the disclosure can be used to detect an analyte mRNA, protein, or genomic DNA in a biological sample in vitro as well as in vivo. For example, in vitro techniques for detection of an analyte mRNA include Northern hybridizations and in situ hybridizations. In vitro techniques for detection of an analyte protein include enzyme linked immunosorbent assays (ELISAs), Western blots, immunoprecipitations, immunochemical staining, and immunofluorescence. In vitro techniques for detection of an analyte genomic DNA include Southern hybridizations. Procedures for conducting immunoassays are described, for example in “ELISA: Theory and Practice: Methods in Molecular Biology”, Vol. 42, J. R. Crowther (Ed.) Human Press, Totowa, N.J., 1995; “Immunoassay”, E. Diamandis and T. Christopoulus, Academic Press, Inc., San Diego, Calif., 1996; and “Practice and Theory of Enzyme Immunoassays”, P. Tijssen, Elsevier Science Publishers, Amsterdam, 1985. Furthermore, in vivo techniques for detection of an analyte protein include introducing into a subject a labeled anti-analyte protein antibody. For example, the antibody can be labeled with a radioactive marker whose presence and location in a subject can be detected by standard imaging techniques.
• The antibodies and/or activatable antibodies of the disclosure are also useful in a variety of diagnostic and prophylactic formulations. In one embodiment, an antibody and/or an activatable antibody is administered to patients that are at risk of developing one or more of the aforementioned disorders. A patient's or organ's predisposition to one or more of the aforementioned disorders can be determined using genotypic, serological or biochemical markers.
• In some embodiments of the disclosure, an antibody and/or an activatable antibody is administered to human individuals diagnosed with a clinical indication associated with one or more of the aforementioned disorders. Upon diagnosis, an antibody and/or an activatable antibody is administered to mitigate or reverse the effects of the clinical indication.
• An antibody and/or an activatable antibody of the disclosure is also useful in the detection of a target in patient samples and accordingly are useful as diagnostics. For example, the antibodies and/or activatable antibodies, and conjugated versions thereof, of the disclosure are used in in vitro assays, e.g., ELISA, to detect target levels in a patient sample.
• In some embodiments, anti-PDL1 antibodies are used as a diagnostic for patients who are more likely to respond favorably to treatment with an anti-PD-1 antibody and/or activatable antibody of the disclosure. In these embodiments, PD-L1 expression in tumor biopsies on both tumor cells and infiltrating immune cells and PD-L1 expression on immune cells in blood are used to indicate the presence of active immunity and, thus, potential for suppression of T cell activity through the engagement of PD-1 by PD-L1.
• In one embodiment, an antibody, a conjugated antibody, an activatable antibody and/or a conjugated activatable antibody of the disclosure is immobilized on a solid support (e.g., the well(s) of a microtiter plate). The immobilized antibody, conjugated antibody, activatable antibody and/or conjugated activatable antibody serves as a capture antibody for any target that can be present in a test sample. Prior to contacting the immobilized antibody and/or activatable antibody, and/or conjugated versions thereof, with a patient sample, the solid support is rinsed and treated with a blocking agent such as milk protein or albumin to prevent nonspecific adsorption of the analyte.
• Subsequently the wells are treated with a test sample suspected of containing the antigen, or with a solution containing a standard amount of the antigen. Such a sample is, e.g., a serum sample from a subject suspected of having levels of circulating antigen considered to be diagnostic of a pathology. After rinsing away the test sample or standard, the solid support is treated with a second antibody that is detectably labeled. The labeled second antibody serves as a detecting antibody. The level of detectable label is measured, and the concentration of target antigen in the test sample is determined by comparison with a standard curve developed from the standard samples.
• It will be appreciated that based on the results obtained using the antibodies and activatable antibodies of the disclosure, and conjugated versions thereof, in an in vitro diagnostic assay, it is possible to stage a disease in a subject based on expression levels of the target antigen. For a given disease, samples of blood are taken from subjects diagnosed as being at various stages in the progression of the disease, and/or at various points in the therapeutic treatment of the disease. Using a population of samples that provides statistically significant results for each stage of progression or therapy, a range of concentrations of the antigen that can be considered characteristic of each stage is designated.
• An antibody, a conjugated antibody, an activatable antibody and/or a conjugated activatable antibody can also be used in diagnostic and/or imaging methods. In some embodiments, such methods are in vitro methods. In some embodiments, such methods are in vivo methods. In some embodiments, such methods are in situ methods. In some embodiments, such methods are ex vivo methods. For example, activatable antibodies having an enzymatically cleavable CM can be used to detect the presence or absence of an enzyme that is capable of cleaving the CM. Such activatable antibodies can be used in diagnostics, which can include in vivo detection (e.g., qualitative or quantitative) of enzyme activity (or, in some embodiments, an environment of increased reduction potential such as that which can provide for reduction of a disulfide bond) through measured accumulation of activated antibodies (i.e., antibodies resulting from cleavage of an activatable antibody) in a given cell or tissue of a given host organism. Such accumulation of activated antibodies indicates not only that the tissue expresses enzymatic activity (or an increased reduction potential depending on the nature of the CM) but also that the tissue expresses target to which the activated antibody binds.
• For example, the CM can be selected to be substrate for at least one protease found at the site of a tumor, at the site of a viral or bacterial infection at a biologically confined site (e.g., such as in an abscess, in an organ, and the like), and the like. The AB can be one that binds a target antigen. Using methods as disclosed herein, or when appropriate, methods familiar to one skilled in the art, a detectable label (e.g., a fluorescent label or radioactive label or radiotracer) can be conjugated to an AB or other region of an antibody and/or activatable antibody. Suitable detectable labels are discussed in the context of the above screening methods and additional specific examples are provided below. Using an AB specific to a protein or peptide of the disease state, along with at least one protease whose activity is elevated in the disease tissue of interest, activatable antibodies will exhibit an increased rate of binding to disease tissue relative to tissues where the CM specific enzyme is not present at a detectable level or is present at a lower level than in disease tissue or is inactive (e.g., in zymogen form or in complex with an inhibitor). Since small proteins and peptides are rapidly cleared from the blood by the renal filtration system, and because the enzyme specific for the CM is not present at a detectable level (or is present at lower levels in non-disease tissues or is present in inactive conformation), accumulation of activated antibodies in the disease tissue is enhanced relative to non-disease tissues.
• In another example, activatable antibodies can be used to detect the presence or absence of a cleaving agent in a sample. For example, where the activatable antibodies contain a CM susceptible to cleavage by an enzyme, the activatable antibodies can be used to detect (either qualitatively or quantitatively) the presence of an enzyme in the sample. In another example, where the activatable antibodies contain a CM susceptible to cleavage by reducing agent, the activatable antibodies can be used to detect (either qualitatively or quantitatively) the presence of reducing conditions in a sample. To facilitate analysis in these methods, the activatable antibodies can be detectably labeled, and can be bound to a support (e.g., a solid support, such as a slide or bead). The detectable label can be positioned on a portion of the activatable antibody that is not released following cleavage, for example, the detectable label can be a quenched fluorescent label or other label that is not detectable until cleavage has occurred. The assay can be conducted by, for example, contacting the immobilized, detectably labeled activatable antibodies with a sample suspected of containing an enzyme and/or reducing agent for a time sufficient for cleavage to occur, then washing to remove excess sample and contaminants. The presence or absence of the cleaving agent (e.g., enzyme or reducing agent) in the sample is then assessed by a change in detectable signal of the activatable antibodies prior to contacting with the sample e.g., the presence of and/or an increase in detectable signal due to cleavage of the activatable antibody by the cleaving agent in the sample.
• Such detection methods can be adapted to also provide for detection of the presence or absence of a target that is capable of binding the AB of the activatable antibodies when cleaved. Thus, the assays can be adapted to assess the presence or absence of a cleaving agent and the presence or absence of a target of interest. The presence or absence of the cleaving agent can be detected by the presence of and/or an increase in detectable label of the activatable antibodies as described above, and the presence or absence of the target can be detected by detection of a target-AB complex e.g., by use of a detectably labeled anti-target antibody.
• Activatable antibodies are also useful in in situ imaging for the validation of activatable antibody activation, e.g., by protease cleavage, and binding to a particular target. In situ imaging is a technique that enables localization of proteolytic activity and target in biological samples such as cell cultures or tissue sections. Using this technique, it is possible to confirm both binding to a given target and proteolytic activity based on the presence of a detectable label (e.g., a fluorescent label).
• These techniques are useful with any frozen cells or tissue derived from a disease site (e.g. tumor tissue) or healthy tissues. These techniques are also useful with fresh cell or tissue samples.
• In these techniques, an activatable antibody is labeled with a detectable label. The detectable label can be a fluorescent dye, (e.g. a fluorophore, Fluorescein Isothiocyanate (FITC), Rhodamine Isothiocyanate (TRITC), an Alexa Fluor® label), a near infrared (NIR) dye (e.g., Qdot® nanocrystals), a colloidal metal, a hapten, a radioactive marker, biotin and an amplification reagent such as streptavidin, or an enzyme (e.g. horseradish peroxidase or alkaline phosphatase).
• Detection of the label in a sample that has been incubated with the labeled, activatable antibody indicates that the sample contains the target and contains a protease that is specific for the CM of the activatable antibody. In some embodiments, the presence of the protease can be confirmed using broad spectrum protease inhibitors such as those described herein, and/or by using an agent that is specific for the protease, for example, an antibody such as A11, which is specific for the protease matriptase and inhibits the proteolytic activity of matriptase; see e.g., International Publication Number WO 2010/129609, published 11 Nov. 2010. The same approach of using broad spectrum protease inhibitors such as those described herein, and/or by using a more selective inhibitory agent can be used to identify a protease that is specific for the CM of the activatable antibody. In some embodiments, the presence of the target can be confirmed using an agent that is specific for the target, e.g., another antibody, or the detectable label can be competed with unlabeled target. In some embodiments, unlabeled activatable antibody could be used, with detection by a labeled secondary antibody or more complex detection system.
• Similar techniques are also useful for in vivo imaging where detection of the fluorescent signal in a subject, e.g., a mammal, including a human, indicates that the disease site contains the target and contains a protease that is specific for the CM of the activatable antibody.
• These techniques are also useful in kits and/or as reagents for the detection, identification or characterization of protease activity in a variety of cells, tissues, and organisms based on the protease-specific CM in the activatable antibody.
• The disclosure provides methods of using the antibodies and/or activatable antibodies in a variety of diagnostic and/or prophylactic indications. For example, the disclosure provides methods of detecting presence or absence of a cleaving agent and a target of interest in a subject or a sample by (i) contacting a subject or sample with an activatable antibody, wherein the activatable antibody comprises a masking moiety (MM), a cleavable moiety (CM) that is cleaved by the cleaving agent, e.g., a protease, and an antigen binding domain or fragment thereof (AB) that specifically binds the target of interest, wherein the activatable antibody in an uncleaved, non-activated state comprises a structural arrangement from N-terminus to C-terminus as follows: MM-CM-AB or AB-CM-MM; (a) wherein the MM is a peptide that inhibits binding of the AB to the target, and wherein the MM does not have an amino acid sequence of a naturally occurring binding partner of the AB and is not a modified form of a natural binding partner of the AB; and (b) wherein, in an uncleaved, non-activated state, the MM interferes with specific binding of the AB to the target, and in a cleaved, activated state the MM does not interfere or compete with specific binding of the AB to the target; and (ii) measuring a level of activated activatable antibody in the subject or sample, wherein a detectable level of activated activatable antibody in the subject or sample indicates that the cleaving agent and the target are present in the subject or sample and wherein no detectable level of activated activatable antibody in the subject or sample indicates that the cleaving agent, the target or both the cleaving agent and the target are absent and/or not sufficiently present in the subject or sample. In some embodiments, the activatable antibody is an activatable antibody to which a therapeutic agent is conjugated. In some embodiments, the activatable antibody is not conjugated to an agent. In some embodiments, the activatable antibody comprises a detectable label. In some embodiments, the detectable label is positioned on the AB. In some embodiments, measuring the level of activatable antibody in the subject or sample is accomplished using a secondary reagent that specifically binds to the activated antibody, wherein the reagent comprises a detectable label. In some embodiments, the secondary reagent is an antibody comprising a detectable label.
• The disclosure also provides methods of detecting presence or absence of a cleaving agent in a subject or a sample by (i) contacting a subject or sample with an activatable antibody in the presence of a target of interest, e.g., the target, wherein the activatable antibody comprises a masking moiety (MM), a cleavable moiety (CM) that is cleaved by the cleaving agent, e.g., a protease, and an antigen binding domain or fragment thereof (AB) that specifically binds the target of interest, wherein the activatable antibody in an uncleaved, non-activated state comprises a structural arrangement from N-terminus to C-terminus as follows: MM-CM-AB or AB-CM-MM; (a) wherein the MM is a peptide that inhibits binding of the AB to the target, and wherein the MM does not have an amino acid sequence of a naturally occurring binding partner of the AB and is not a modified form of a natural binding partner of the AB; and (b) wherein, in an uncleaved, non-activated state, the MM interferes with specific binding of the AB to the target, and in a cleaved, activated state the MM does not interfere or compete with specific binding of the AB to the target; and (ii) measuring a level of activated activatable antibody in the subject or sample, wherein a detectable level of activated activatable antibody in the subject or sample indicates that the cleaving agent is present in the subject or sample and wherein no detectable level of activated activatable antibody in the subject or sample indicates that the cleaving agent is absent and/or not sufficiently present in the subject or sample. In some embodiments, the activatable antibody is an activatable antibody to which a therapeutic agent is conjugated. In some embodiments, the activatable antibody is not conjugated to an agent. In some embodiments, the activatable antibody comprises a detectable label. In some embodiments, the detectable label is positioned on the AB. In some embodiments, measuring the level of activatable antibody in the subject or sample is accomplished using a secondary reagent that specifically binds to the activated antibody, wherein the reagent comprises a detectable label. In some embodiments, the secondary reagent is an antibody comprising a detectable label.
• The disclosure also provides kits for use in methods of detecting presence or absence of a cleaving agent and the target in a subject or a sample, where the kits include at least an activatable antibody comprises a masking moiety (MM), a cleavable moiety (CM) that is cleaved by the cleaving agent, e.g., a protease, and an antigen binding domain or fragment thereof (AB) that specifically binds the target of interest, wherein the activatable antibody in an uncleaved, non-activated state comprises a structural arrangement from N-terminus to C-terminus as follows: MM-CM-AB or AB-CM-MM; (a) wherein the MM is a peptide that inhibits binding of the AB to the target, and wherein the MM does not have an amino acid sequence of a naturally occurring binding partner of the AB and is not a modified form of a natural binding partner of the AB; and (b) wherein, in an uncleaved, non-activated state, the MM interferes with specific binding of the AB to the target, and in a cleaved, activated state the MM does not interfere or compete with specific binding of the AB to the target; and (ii) measuring a level of activated activatable antibody in the subject or sample, wherein a detectable level of activated activatable antibody in the subject or sample indicates that the cleaving agent is present in the subject or sample and wherein no detectable level of activated activatable antibody in the subject or sample indicates that the cleaving agent is absent and/or not sufficiently present in the subject or sample. In some embodiments, the activatable antibody is an activatable antibody to which a therapeutic agent is conjugated. In some embodiments, the activatable antibody is not conjugated to an agent. In some embodiments, the activatable antibody comprises a detectable label. In some embodiments, the detectable label is positioned on the AB. In some embodiments, measuring the level of activatable antibody in the subject or sample is accomplished using a secondary reagent that specifically binds to the activated antibody, wherein the reagent comprises a detectable label. In some embodiments, the secondary reagent is an antibody comprising a detectable label.
• The disclosure also provides methods of detecting presence or absence of a cleaving agent in a subject or a sample by (i) contacting a subject or sample with an activatable antibody, wherein the activatable antibody comprises a masking moiety (MM), a cleavable moiety (CM) that is cleaved by the cleaving agent, e.g., a protease, an antigen binding domain (AB) that specifically binds the target, and a detectable label, wherein the activatable antibody in an uncleaved, non-activated state comprises a structural arrangement from N-terminus to C-terminus as follows: MM-CM-AB or AB-CM-MM; wherein the MM is a peptide that inhibits binding of the AB to the target, and wherein the MM does not have an amino acid sequence of a naturally occurring binding partner of the AB and is not a modified form of a natural binding partner of the AB; wherein, in an uncleaved, non-activated state, the MM interferes with specific binding of the AB to the target, and in a cleaved, activated state the MM does not interfere or compete with specific binding of the AB to the target; and wherein the detectable label is positioned on a portion of the activatable antibody that is released following cleavage of the CM; and (ii) measuring a level of detectable label in the subject or sample, wherein a detectable level of the detectable label in the subject or sample indicates that the cleaving agent is absent and/or not sufficiently present in the subject or sample and wherein no detectable level of the detectable label in the subject or sample indicates that the cleaving agent is present in the subject or sample. In some embodiments, the activatable antibody is an activatable antibody to which a therapeutic agent is conjugated. In some embodiments, the activatable antibody is not conjugated to an agent. In some embodiments, the activatable antibody comprises a detectable label. In some embodiments, the detectable label is positioned on the AB. In some embodiments, measuring the level of activatable antibody in the subject or sample is accomplished using a secondary reagent that specifically binds to the activated antibody, wherein the reagent comprises a detectable label. In some embodiments, the secondary reagent is an antibody comprising a detectable label.
• The disclosure also provides kits for use in methods of detecting presence or absence of a cleaving agent and the target in a subject or a sample, where the kits include at least an activatable antibody and/or conjugated activatable antibody (e.g., an activatable antibody to which a therapeutic agent is conjugated) described herein for use in contacting a subject or biological sample and means for detecting the level of activated activatable antibody and/or conjugated activatable antibody in the subject or biological sample, wherein a detectable level of activated activatable antibody in the subject or biological sample indicates that the cleaving agent and the target are present in the subject or biological sample and wherein no detectable level of activated activatable antibody in the subject or biological sample indicates that the cleaving agent, the target or both the cleaving agent and the target are absent and/or not sufficiently present in the subject or biological sample, such that the target binding and/or protease cleavage of the activatable antibody cannot be detected in the subject or biological sample.
• The disclosure also provides methods of detecting presence or absence of a cleaving agent in a subject or a sample by (i) contacting a subject or biological sample with an activatable antibody in the presence of the target, and (ii) measuring a level of activated activatable antibody in the subject or biological sample, wherein a detectable level of activated activatable antibody in the subject or biological sample indicates that the cleaving agent is present in the subject or biological sample and wherein no detectable level of activated activatable antibody in the subject or biological sample indicates that the cleaving agent is absent and/or not sufficiently present in the subject or biological sample at a detectable level, such that protease cleavage of the activatable antibody cannot be detected in the subject or biological sample. Such an activatable antibody includes a masking moiety (MM), a cleavable moiety (CM) that is cleaved by the cleaving agent, e.g., a protease, and an antigen binding domain or fragment thereof (AB) that specifically binds the target, wherein the activatable antibody in an uncleaved (i.e., non-activated) state comprises a structural arrangement from N-terminus to C-terminus as follows: MM-CM-AB or AB-CM-MM; (a) wherein the MM is a peptide that inhibits binding of the AB to the target, and wherein the MM does not have an amino acid sequence of a naturally occurring binding partner of the AB; and (b) wherein the MM of the activatable antibody in an uncleaved state interferes with specific binding of the AB to the target, and wherein the MM of an activatable antibody in a cleaved (i.e., activated) state does not interfere or compete with specific binding of the AB to the target. In some embodiments, the activatable antibody is an activatable antibody to which a therapeutic agent is conjugated. In some embodiments, the activatable antibody is not conjugated to an agent. In some embodiments, the detectable label is attached to the masking moiety. In some embodiments, the detectable label is attached to the cleavable moiety N-terminal to the protease cleavage site. In some embodiments, a single antigen binding site of the AB is masked. In some embodiments wherein an antibody of the disclosure has at least two antigen binding sites, at least one antigen binding site is masked and at least one antigen binding site is not masked. In some embodiments all antigen binding sites are masked. In some embodiments, the measuring step includes use of a secondary reagent comprising a detectable label.
• The disclosure also provides kits for use in methods of detecting presence or absence of a cleaving agent and the target in a subject or a sample, where the kits include at least an activatable antibody and/or conjugated activatable antibody described herein for use in contacting a subject or biological sample with an activatable antibody in the presence of the target, and measuring a level of activated activatable antibody in the subject or biological sample, wherein a detectable level of activated activatable antibody in the subject or biological sample indicates that the cleaving agent is present in the subject or biological sample and wherein no detectable level of activated activatable antibody in the subject or biological sample indicates that the cleaving agent is absent and/or not sufficiently present in the subject or biological sample at a detectable level, such that protease cleavage of the activatable antibody cannot be detected in the subject or biological sample. Such an activatable antibody includes a masking moiety (MM), a cleavable moiety (CM) that is cleaved by the cleaving agent, e.g., a protease, and an antigen binding domain or fragment thereof (AB) that specifically binds the target, wherein the activatable antibody in an uncleaved (i.e., non-activated) state comprises a structural arrangement from N-terminus to C-terminus as follows: MM-CM-AB or AB-CM-MM; (a) wherein the MM is a peptide that inhibits binding of the AB to the target, and wherein the MM does not have an amino acid sequence of a naturally occurring binding partner of the AB; and (b) wherein the MM of the activatable antibody in an uncleaved state interferes with specific binding of the AB to the target, and wherein the MM of an activatable antibody in a cleaved (i.e., activated) state does not interfere or compete with specific binding of the AB to the target. In some embodiments, the activatable antibody is an activatable antibody to which a therapeutic agent is conjugated. In some embodiments, the activatable antibody is not conjugated to an agent. In some embodiments, the detectable label is attached to the masking moiety. In some embodiments, the detectable label is attached to the cleavable moiety N-terminal to the protease cleavage site. In some embodiments, a single antigen binding site of the AB is masked. In some embodiments wherein an antibody of the disclosure has at least two antigen binding sites, at least one antigen binding site is masked and at least one antigen binding site is not masked. In some embodiments all antigen binding sites are masked. In some embodiments, the measuring step includes use of a secondary reagent comprising a detectable label.
• The disclosure also provides kits for use in methods of detecting presence or absence of a cleaving agent in a subject or a sample, where the kits include at least an activatable antibody and/or conjugated activatable antibody described herein for use in contacting a subject or biological sample and means for detecting the level of activated activatable antibody and/or conjugated activatable antibody in the subject or biological sample, wherein the activatable antibody includes a detectable label that is positioned on a portion of the activatable antibody that is released following cleavage of the CM, wherein a detectable level of activated activatable antibody in the subject or biological sample indicates that the cleaving agent is absent and/or not sufficiently present in the subject or biological sample such that the target binding and/or protease cleavage of the activatable antibody cannot be detected in the subject or biological sample, and wherein no detectable level of activated activatable antibody in the subject or biological sample indicates that the cleaving agent is present in the subject or biological sample at a detectable level.
• The disclosure provides methods of detecting presence or absence of a cleaving agent and the target in a subject or a sample by (i) contacting a subject or biological sample with an activatable antibody, wherein the activatable antibody includes a detectable label that is positioned on a portion of the activatable antibody that is released following cleavage of the CM and (ii) measuring a level of activated activatable antibody in the subject or biological sample, wherein a detectable level of activated activatable antibody in the subject or biological sample indicates that the cleaving agent, the target or both the cleaving agent and the target are absent and/or not sufficiently present in the subject or biological sample, such that the target binding and/or protease cleavage of the activatable antibody cannot be detected in the subject or biological sample, and wherein a reduced detectable level of activated activatable antibody in the subject or biological sample indicates that the cleaving agent and the target are present in the subject or biological sample. A reduced level of detectable label is, for example, a reduction of about 5%, about 10%, about 15%, about 20%, about 25%, about 30%, about 35%, about 40%, about 45%, about 50%, about 55%, about 60%, about 65%, about 70%, about 75%, about 80%, about 85%, about 90%, about 95% and/or about 100%. Such an activatable antibody includes a masking moiety (MM), a cleavable moiety (CM) that is cleaved by the cleaving agent, and an antigen binding domain or fragment thereof (AB) that specifically binds the target, wherein the activatable antibody in an uncleaved (i.e., non-activated) state comprises a structural arrangement from N-terminus to C-terminus as follows: MM-CM-AB or AB-CM-MM; (a) wherein the MM is a peptide that inhibits binding of the AB to the target, and wherein the MM does not have an amino acid sequence of a naturally occurring binding partner of the AB; and (b) wherein the MM of the activatable antibody in an uncleaved state interferes with specific binding of the AB to the target, and wherein the MM of an activatable antibody in a cleaved (i.e., activated) state does not interfere or compete with specific binding of the AB to the target. In some embodiments, the activatable antibody is an activatable antibody to which a therapeutic agent is conjugated. In some embodiments, the activatable antibody is not conjugated to an agent. In some embodiments, the activatable antibody comprises a detectable label. In some embodiments, the detectable label is positioned on the AB. In some embodiments, measuring the level of activatable antibody in the subject or sample is accomplished using a secondary reagent that specifically binds to the activated antibody, wherein the reagent comprises a detectable label. In some embodiments, the secondary reagent is an antibody comprising a detectable label.
• The disclosure also provides kits for use in methods of detecting presence or absence of a cleaving agent and the target in a subject or a sample, where the kits include at least an activatable antibody and/or conjugated activatable antibody described herein for use in contacting a subject or biological sample and means for detecting the level of activated activatable antibody and/or conjugated activatable antibody in the subject or biological sample, wherein a detectable level of activated activatable antibody in the subject or biological sample indicates that the cleaving agent, the target or both the cleaving agent and the target are absent and/or not sufficiently present in the subject or biological sample, such that the target binding and/or protease cleavage of the activatable antibody cannot be detected in the subject or biological sample, and wherein a reduced detectable level of activated activatable antibody in the subject or biological sample indicates that the cleaving agent and the target are present in the subject or biological sample. A reduced level of detectable label is, for example, a reduction of about 5%, about 10%, about 15%, about 20%, about 25%, about 30%, about 35%, about 40%, about 45%, about 50%, about 55%, about 60%, about 65%, about 70%, about 75%, about 80%, about 85%, about 90%, about 95% and/or about 100%.
• The disclosure also provides methods of detecting presence or absence of a cleaving agent in a subject or a sample by (i) contacting a subject or biological sample with an activatable antibody, wherein the activatable antibody includes a detectable label that is positioned on a portion of the activatable antibody that is released following cleavage of the CM; and (ii) measuring a level of detectable label in the subject or biological sample, wherein a detectable level of the detectable label in the subject or biological sample indicates that the cleaving agent is absent and/or not sufficiently present in the subject or biological sample at a detectable level, such that protease cleavage of the activatable antibody cannot be detected in the subject or biological sample, and wherein a reduced detectable level of the detectable label in the subject or biological sample indicates that the cleaving agent is present in the subject or biological sample. A reduced level of detectable label is, for example, a reduction of about 5%, about 10%, about 15%, about 20%, about 25%, about 30%, about 35%, about 40%, about 45%, about 50%, about 55%, about 60%, about 65%, about 70%, about 75%, about 80%, about 85%, about 90%, about 95% and/or about 100%. Such an activatable antibody includes a masking moiety (MM), a cleavable moiety (CM) that is cleaved by the cleaving agent, and an antigen binding domain or fragment thereof (AB) that specifically binds the target, wherein the activatable antibody in an uncleaved (i.e., non-activated) state comprises a structural arrangement from N-terminus to C-terminus as follows: MM-CM-AB or AB-CM-MM; (a) wherein the MM is a peptide that inhibits binding of the AB to the target, and wherein the MM does not have an amino acid sequence of a naturally occurring binding partner of the AB; and (b) wherein the MM of the activatable antibody in an uncleaved state interferes with specific binding of the AB to the target, and wherein the MM of an activatable antibody in a cleaved (i.e., activated) state does not interfere or compete with specific binding of the AB to the target. In some embodiments, the activatable antibody is an activatable antibody to which a therapeutic agent is conjugated. In some embodiments, the activatable antibody is not conjugated to an agent. In some embodiments, the activatable antibody comprises a detectable label. In some embodiments, the detectable label is positioned on the AB. In some embodiments, measuring the level of activatable antibody in the subject or sample is accomplished using a secondary reagent that specifically binds to the activated antibody, wherein the reagent comprises a detectable label. In some embodiments, the secondary reagent is an antibody comprising a detectable label.
• The disclosure also provides kits for use in methods of detecting presence or absence of a cleaving agent of interest in a subject or a sample, where the kits include at least an activatable antibody and/or conjugated activatable antibody described herein for use in contacting a subject or biological sample and means for detecting the level of activated activatable antibody and/or conjugated activatable antibody in the subject or biological sample, wherein the activatable antibody includes a detectable label that is positioned on a portion of the activatable antibody that is released following cleavage of the CM, wherein a detectable level of the detectable label in the subject or biological sample indicates that the cleaving agent, the target, or both the cleaving agent and the target are absent and/or not sufficiently present in the subject or biological sample, such that the target binding and/or protease cleavage of the activatable antibody cannot be detected in the subject or biological sample, and wherein a reduced detectable level of the detectable label in the subject or biological sample indicates that the cleaving agent and the target are present in the subject or biological sample. A reduced level of detectable label is, for example, a reduction of about 5%, about 10%, about 15%, about 20%, about 25%, about 30%, about 35%, about 40%, about 45%, about 50%, about 55%, about 60%, about 65%, about 70%, about 75%, about 80%, about 85%, about 90%, about 95% and/or about 100%.
• In some embodiments of these methods and kits, the activatable antibody includes a detectable label. In some embodiments of these methods and kits, the detectable label includes an imaging agent, a contrasting agent, an enzyme, a fluorescent label, a chromophore, a dye, one or more metal ions, or a ligand-based label. In some embodiments of these methods and kits, the imaging agent comprises a radioisotope. In some embodiments of these methods and kits, the radioisotope is indium or technetium. In some embodiments of these methods and kits, the contrasting agent comprises iodine, gadolinium or iron oxide. In some embodiments of these methods and kits, the enzyme comprises horseradish peroxidase, alkaline phosphatase, or (3-galactosidase. In some embodiments of these methods and kits, the fluorescent label comprises yellow fluorescent protein (YFP), cyan fluorescent protein (CFP), green fluorescent protein (GFP), modified red fluorescent protein (mRFP), red fluorescent protein tdimer2 (RFP tdimer2), HCRED, or a europium derivative. In some embodiments of these methods and kits, the luminescent label comprises an N-methylacrydium derivative. In some embodiments of these methods, the label comprises an Alexa Fluor® label, such as Alex Fluor® 680 or Alexa Fluor® 750. In some embodiments of these methods and kits, the ligand-based label comprises biotin, avidin, streptavidin or one or more haptens.
• In some embodiments of these methods and kits, the subject is a mammal. In some embodiments of these methods and kits, the subject is a human. In some embodiments, the subject is a non-human mammal, such as a non-human primate, companion animal (e.g., cat, dog, horse), farm animal, work animal, or zoo animal. In some embodiments, the subject is a rodent.
• In some embodiments of these methods, the method is an in vivo method. In some embodiments of these methods, the method is an in situ method. In some embodiments of these methods, the method is an ex vivo method. In some embodiments of these methods, the method is an in vitro method.
• In some embodiments, in situ imaging and/or in vivo imaging are useful in methods to identify which patients to treat. For example, in in situ imaging, the activatable antibodies are used to screen patient samples to identify those patients having the appropriate protease(s) and target(s) at the appropriate location, e.g., at a tumor site.
• In some embodiments in situ imaging is used to identify or otherwise refine a patient population suitable for treatment with an activatable antibody of the disclosure. For example, patients that test positive for both the target (e.g., the target) and a protease that cleaves the substrate in the cleavable moiety (CM) of the activatable antibody being tested (e.g., accumulate activated antibodies at the disease site) are identified as suitable candidates for treatment with such an activatable antibody comprising such a CM. Likewise, patients that test negative for either or both of the target (e.g., the target) and the protease that cleaves the substrate in the CM in the activatable antibody being tested using these methods might be identified as suitable candidates for another form of therapy. In some embodiments, such patients that test negative with respect to a first activatable antibody can be tested with other activatable antibodies comprising different CMs until a suitable activatable antibody for treatment is identified (e.g., an activatable antibody comprising a CM that is cleaved by the patient at the site of disease). In some embodiments, the patient is then administered a therapeutically effective amount of the activatable antibody for which the patient tested positive.
• In some embodiments in vivo imaging is used to identify or otherwise refine a patient population suitable for treatment with an activatable antibody of the disclosure. For example, patients that test positive for both the target (e.g., the target) and a protease that cleaves the substrate in the cleavable moiety (CM) of the activatable antibody being tested (e.g., accumulate activated antibodies at the disease site) are identified as suitable candidates for treatment with such an activatable antibody comprising such a CM. Likewise, patients that test negative might be identified as suitable candidates for another form of therapy. In some embodiments, such patients that test negative with respect to a first activatable antibody can be tested with other activatable antibodies comprising different CMs until a suitable activatable antibody for treatment is identified (e.g., an activatable antibody comprising a CM that is cleaved by the patient at the site of disease). In some embodiments, the patient is then administered a therapeutically effective amount of the activatable antibody for which the patient tested positive.
• In some embodiments of the methods and kits, the method or kit is used to identify or otherwise refine a patient population suitable for treatment with an activatable antibody of the disclosure. For example, patients that test positive for both the target (e.g., the target) and a protease that cleaves the substrate in the cleavable moiety (CM) of the activatable antibody being tested in these methods are identified as suitable candidates for treatment with such an activatable antibody comprising such a CM. Likewise, patients that test negative for both of the targets (e.g., the target) and the protease that cleaves the substrate in the CM in the activatable antibody being tested using these methods might be identified as suitable candidates for another form of therapy. In some embodiments, such patients can be tested with other activatable antibodies until a suitable activatable antibody for treatment is identified (e.g., an activatable antibody comprising a CM that is cleaved by the patient at the site of disease). In some embodiments, patients that test negative for either of the target (e.g., the target) are identified as suitable candidates for treatment with such an activatable antibody comprising such a CM. In some embodiments, patients that test negative for either of the target (e.g., the target) are identified as not being suitable candidates for treatment with such an activatable antibody comprising such a CM. In some embodiments, such patients can be tested with other activatable antibodies until a suitable activatable antibody for treatment is identified (e.g., an activatable antibody comprising a CM that is cleaved by the patient at the site of disease). In some embodiments, the activatable antibody is an activatable antibody to which a therapeutic agent is conjugated. In some embodiments, the activatable antibody is not conjugated to an agent. In some embodiments, the activatable antibody comprises a detectable label. In some embodiments, the detectable label is positioned on the AB. In some embodiments, measuring the level of activatable antibody in the subject or sample is accomplished using a secondary reagent that specifically binds to the activated antibody, wherein the reagent comprises a detectable label. In some embodiments, the secondary reagent is an antibody comprising a detectable label.
• In some embodiments, a method or kit is used to identify or otherwise refine a patient population suitable for treatment with an anti-the target activatable antibody and/or conjugated activatable antibody (e.g., activatable antibody to which a therapeutic agent is conjugated) of the disclosure, followed by treatment by administering that activatable antibody and/or conjugated activatable antibody to a subject in need thereof. For example, patients that test positive for both the targets (e.g., the target) and a protease that cleaves the substrate in the cleavable moiety (CM) of the activatable antibody and/or conjugated activatable antibody being tested in these methods are identified as suitable candidates for treatment with such antibody and/or such a conjugated activatable antibody comprising such a CM, and the patient is then administered a therapeutically effective amount of the activatable antibody and/or conjugated activatable antibody that was tested. Likewise, patients that test negative for either or both of the target (e.g., the target) and the protease that cleaves the substrate in the CM in the activatable antibody being tested using these methods might be identified as suitable candidates for another form of therapy. In some embodiments, such patients can be tested with other antibody and/or conjugated activatable antibody until a suitable antibody and/or conjugated activatable antibody for treatment is identified (e.g., an activatable antibody and/or conjugated activatable antibody comprising a CM that is cleaved by the patient at the site of disease). In some embodiments, the patient is then administered a therapeutically effective amount of the activatable antibody and/or conjugated activatable antibody for which the patient tested positive.
• In some embodiments of these methods and kits, the MM is a peptide having a length from about 4 to 40 amino acids. In some embodiments of these methods and kits, the activatable antibody comprises a linker peptide, wherein the linker peptide is positioned between the MM and the CM. In some embodiments of these methods and kits, the activatable antibody comprises a linker peptide, where the linker peptide is positioned between the AB and the CM. In some embodiments of these methods and kits, the activatable antibody comprises a first linker peptide (L1) and a second linker peptide (L2), wherein the first linker peptide is positioned between the MM and the CM and the second linker peptide is positioned between the AB and the CM. In some embodiments of these methods and kits, each of L1 and L2 is a peptide of about 1 to 20 amino acids in length, and wherein each of L1 and L2 need not be the same linker. In some embodiments of these methods and kits, one or both of L1 and L2 comprises a glycine-serine polymer. In some embodiments of these methods and kits, at least one of L1 and L2 comprises an amino acid sequence selected from the group consisting of (GS)_n, (GSGGS)_n (SEQ ID NO: 363) and (GGGS)_n (SEQ ID NO: 364), where n is an integer of at least one. In some embodiments of these methods and kits, at least one of L1 and L2 comprises an amino acid sequence having the formula (GGS)_n, where n is an integer of at least one. In some embodiments of these methods and kits, at least one of L1 and L2 comprises an amino acid sequence selected from the group consisting of GGSG (SEQ ID NO: 365), GGSGG (SEQ ID NO: 366), GSGSG (SEQ ID NO: 367), GSGGG (SEQ ID NO: 368), GGGSG (SEQ ID NO: 369), and GSSSG (SEQ ID NO: 370).
• In some embodiments of these methods and kits, the AB comprises an antibody or antibody fragment sequence selected from the cross-reactive antibody sequences presented herein. In some embodiments of these methods and kits, the AB comprises a Fab fragment, a scFv or a single chain antibody (scAb).
• In some embodiments of these methods and kits, the cleaving agent is a protease that is co-localized in the subject or sample with the target and the CM is a polypeptide that functions as a substrate for the protease, wherein the protease cleaves the CM in the activatable antibody when the activatable antibody is exposed to the protease. In some embodiments of these methods and kits, the CM is a polypeptide of up to 15 amino acids in length. In some embodiments of these methods and kits, the CM is coupled to the N-terminus of the AB. In some embodiments of these methods and kits, the CM is coupled to the C-terminus of the AB. In some embodiments of these methods and kits, the CM is coupled to the N-terminus of a VL chain of the AB.
• The antibodies and/or activatable antibodies of the disclosure are used in diagnostic and prophylactic formulations. In one embodiment, an activatable antibody is administered to patients that are at risk of developing one or more of the aforementioned inflammation, inflammatory disorders, cancer or other disorders.
• A patient's or organ's predisposition to one or more of the aforementioned disorders can be determined using genotypic, serological or biochemical markers.
• In some embodiments of the disclosure, an antibody and/or an activatable antibody is administered to human individuals diagnosed with a clinical indication associated with one or more of the aforementioned disorders. Upon diagnosis, an antibody and/or an activatable antibody is administered to mitigate or reverse the effects of the clinical indication.
• Antibodies and/or activatable antibodies of the disclosure are also useful in the detection of the target in patient samples and accordingly are useful as diagnostics. For example, the antibodies and/or activatable antibodies of the disclosure are used in in vitro assays, e.g., ELISA, to detect target levels in a patient sample.
• In some embodiments, anti-PDL1 antibodies are used as a diagnostic for patients who are more likely to respond favorably to treatment with an anti-PD-1 antibody and/or activatable antibody of the disclosure. In these embodiments, PD-L1 expression in tumor biopsies on both tumor cells and infiltrating immune cells and PD-L1 expression on immune cells in blood are used to indicate the presence of active immunity and, thus, potential for suppression of T cell activity through the engagement of PD-1 by PD-L1.
• In one embodiment, an antibody and/or activatable antibody of the disclosure is immobilized on a solid support (e.g., the well(s) of a microtiter plate). The immobilized antibody and/or activatable antibody serves as a capture antibody for any target that can be present in a test sample. Prior to contacting the immobilized antibody and/or activatable antibody with a patient sample, the solid support is rinsed and treated with a blocking agent such as milk protein or albumin to prevent nonspecific adsorption of the analyte.
• Subsequently the wells are treated with a test sample suspected of containing the antigen, or with a solution containing a standard amount of the antigen. Such a sample is, e.g., a serum sample from a subject suspected of having levels of circulating antigen considered to be diagnostic of a pathology. After rinsing away the test sample or standard, the solid support is treated with a second antibody that is detectably labeled. The labeled second antibody serves as a detecting antibody. The level of detectable label is measured, and the concentration of target antigen in the test sample is determined by comparison with a standard curve developed from the standard samples.
• It will be appreciated that based on the results obtained using the antibodies and/or activatable antibodies of the disclosure in an in vitro diagnostic assay, it is possible to stage a disease in a subject based on expression levels of the target antigen. For a given disease, samples of blood are taken from subjects diagnosed as being at various stages in the progression of the disease, and/or at various points in the therapeutic treatment of the disease. Using a population of samples that provides statistically significant results for each stage of progression or therapy, a range of concentrations of the antigen that can be considered characteristic of each stage is designated.
• Antibodies, conjugated antibodies, activatable antibodies and/or conjugated activatable antibodies can also be used in diagnostic and/or imaging methods. In some embodiments, such methods are in vitro methods. In some embodiments, such methods are in vivo methods. In some embodiments, such methods are in situ methods. In some embodiments, such methods are ex vivo methods. For example, activatable antibodies having an enzymatically cleavable CM can be used to detect the presence or absence of an enzyme that is capable of cleaving the CM. Such activatable antibodies can be used in diagnostics, which can include in vivo detection (e.g., qualitative or quantitative) of enzyme activity (or, in some embodiments, an environment of increased reduction potential such as that which can provide for reduction of a disulfide bond) through measured accumulation of activated antibodies (i.e., antibodies resulting from cleavage of an activatable antibody) in a given cell or tissue of a given host organism. Such accumulation of activated antibodies indicates not only that the tissue expresses enzymatic activity (or an increased reduction potential depending on the nature of the CM) but also that the tissue expresses target to which the activated antibody binds.
• For example, the CM can be selected to be a protease substrate for a protease found at the site of a tumor, at the site of a viral or bacterial infection at a biologically confined site (e.g., such as in an abscess, in an organ, and the like), and the like. The AB can be one that binds a target antigen. Using methods familiar to one skilled in the art, a detectable label (e.g., a fluorescent label or radioactive label or radiotracer) can be conjugated to an AB or other region of an activatable antibody. Suitable detectable labels are discussed in the context of the above screening methods and additional specific examples are provided below. Using an AB specific to a protein or peptide of the disease state, along with a protease whose activity is elevated in the disease tissue of interest, activatable antibodies will exhibit an increased rate of binding to disease tissue relative to tissues where the CM specific enzyme is not present at a detectable level or is present at a lower level than in disease tissue or is inactive (e.g., in zymogen form or in complex with an inhibitor). Since small proteins and peptides are rapidly cleared from the blood by the renal filtration system, and because the enzyme specific for the CM is not present at a detectable level (or is present at lower levels in non-disease tissues or is present in inactive conformation), accumulation of activated antibodies in the disease tissue is enhanced relative to non-disease tissues.
• In another example, activatable antibodies can be used to detect the presence or absence of a cleaving agent in a sample. For example, where the activatable antibodies contain a CM susceptible to cleavage by an enzyme, the activatable antibodies can be used to detect (either qualitatively or quantitatively) the presence of an enzyme in the sample. In another example, where the activatable antibodies contain a CM susceptible to cleavage by reducing agent, the activatable antibodies can be used to detect (either qualitatively or quantitatively) the presence of reducing conditions in a sample. To facilitate analysis in these methods, the activatable antibodies can be detectably labeled, and can be bound to a support (e.g., a solid support, such as a slide or bead). The detectable label can be positioned on a portion of the activatable antibody that is not released following cleavage, for example, the detectable label can be a quenched fluorescent label or other label that is not detectable until cleavage has occurred. The assay can be conducted by, for example, contacting the immobilized, detectably labeled activatable antibodies with a sample suspected of containing an enzyme and/or reducing agent for a time sufficient for cleavage to occur, then washing to remove excess sample and contaminants. The presence or absence of the cleaving agent (e.g., enzyme or reducing agent) in the sample is then assessed by a change in detectable signal of the activatable antibodies prior to contacting with the sample e.g., the presence of and/or an increase in detectable signal due to cleavage of the activatable antibody by the cleaving agent in the sample.
• Such detection methods can be adapted to also provide for detection of the presence or absence of a target that is capable of binding the AB of the activatable antibodies when cleaved. Thus, the assays can be adapted to assess the presence or absence of a cleaving agent and the presence or absence of a target of interest. The presence or absence of the cleaving agent can be detected by the presence of and/or an increase in detectable label of the activatable antibodies as described above, and the presence or absence of the target can be detected by detection of a target-AB complex e.g., by use of a detectably labeled anti-target antibody.
• Activatable antibodies are also useful in in situ imaging for the validation of activatable antibody activation, e.g., by protease cleavage, and binding to a particular target. In situ imaging is a technique that enables localization of proteolytic activity and target in biological samples such as cell cultures or tissue sections. Using this technique, it is possible to confirm both binding to a given target and proteolytic activity based on the presence of a detectable label (e.g., a fluorescent label).
• These techniques are useful with any frozen cells or tissue derived from a disease site (e.g. tumor tissue) or healthy tissues. These techniques are also useful with fresh cell or tissue samples.
• In these techniques, an activatable antibody is labeled with a detectable label. The detectable label can be a fluorescent dye, (e.g. Fluorescein Isothiocyanate (FITC), Rhodamine Isothiocyanate (TRITC), a near infrared (NIR) dye (e.g., Qdot® nanocrystals), a colloidal metal, a hapten, a radioactive marker, biotin and an amplification reagent such as streptavidin, or an enzyme (e.g. horseradish peroxidase or alkaline phosphatase).
• Detection of the label in a sample that has been incubated with the labeled, activatable antibody indicates that the sample contains the target and contains a protease that is specific for the CM of the activatable antibody. In some embodiments, the presence of the protease can be confirmed using broad spectrum protease inhibitors such as those described herein, and/or by using an agent that is specific for the protease, for example, an antibody such as A11, which is specific for the protease matriptase and inhibits the proteolytic activity of matriptase; see e.g., International Publication Number WO 2010/129609, published 11 Nov. 2010. The same approach of using broad spectrum protease inhibitors such as those described herein, and/or by using a more selective inhibitory agent can be used to identify a protease or class of proteases specific for the CM of the activatable antibody. In some embodiments, the presence of the target can be confirmed using an agent that is specific for the target, e.g., another antibody, or the detectable label can be competed with unlabeled target. In some embodiments, unlabeled activatable antibody could be used, with detection by a labeled secondary antibody or more complex detection system.
• Similar techniques are also useful for in vivo imaging where detection of the fluorescent signal in a subject, e.g., a mammal, including a human, indicates that the disease site contains the target and contains a protease that is specific for the CM of the activatable antibody.
• These techniques are also useful in kits and/or as reagents for the detection, identification or characterization of protease activity in a variety of cells, tissues, and organisms based on the protease-specific CM in the activatable antibody.
• In some embodiments, in situ imaging and/or in vivo imaging are useful in methods to identify which patients to treat. For example, in in situ imaging, the activatable antibodies are used to screen patient samples to identify those patients having the appropriate protease(s) and target(s) at the appropriate location, e.g., at a tumor site.
• In some embodiments in situ imaging is used to identify or otherwise refine a patient population suitable for treatment with an activatable antibody of the disclosure. For example, patients that test positive for both the target and a protease that cleaves the substrate in the cleavable moiety (CM) of the activatable antibody being tested (e.g., accumulate activated antibodies at the disease site) are identified as suitable candidates for treatment with such an activatable antibody comprising such a CM. Likewise, patients that test negative for either or both of the target and the protease that cleaves the substrate in the CM in the activatable antibody being tested using these methods are identified as suitable candidates for another form of therapy (i.e., not suitable for treatment with the activatable antibody being tested). In some embodiments, such patients that test negative with respect to a first activatable antibody can be tested with other activatable antibodies comprising different CMs until a suitable activatable antibody for treatment is identified (e.g., an activatable antibody comprising a CM that is cleaved by the patient at the site of disease).
• In some embodiments in vivo imaging is used to identify or otherwise refine a patient population suitable for treatment with an activatable antibody of the disclosure. For example, patients that test positive for both the target and a protease that cleaves the substrate in the cleavable moiety (CM) of the activatable antibody being tested (e.g., accumulate activated antibodies at the disease site) are identified as suitable candidates for treatment with such an activatable antibody comprising such a CM. Likewise, patients that test negative are identified as suitable candidates for another form of therapy (i.e., not suitable for treatment with the activatable antibody being tested). In some embodiments, such patients that test negative with respect to a first activatable antibody can be tested with other activatable antibodies comprising different CMs until a suitable activatable antibody for treatment is identified (e.g., an activatable antibody comprising a CM that is cleaved by the patient at the site of disease).
• Pharmaceutical Compositions
• The antibodies and/or activatable antibodies of the disclosure (also referred to herein as “active compounds”), and derivatives, fragments, analogs and homologs thereof, can be incorporated into pharmaceutical compositions suitable for administration. Such compositions typically comprise the antibody and/or activatable antibody and a pharmaceutically acceptable carrier. As used herein, the term “pharmaceutically acceptable carrier” is intended to include any and all solvents, dispersion media, coatings, antibacterial and antifungal agents, isotonic and absorption delaying agents, and the like, compatible with pharmaceutical administration. Suitable carriers are described in the most recent edition of Remington's Pharmaceutical Sciences, a standard reference text in the field, which is incorporated herein by reference. Suitable examples of such carriers or diluents include, but are not limited to, water, saline, ringer's solutions, dextrose solution, and 5% human serum albumin. Liposomes and non-aqueous vehicles such as fixed oils can also be used. The use of such media and agents for pharmaceutically active substances is well known in the art. Except insofar as any conventional media or agent is incompatible with the active compound, use thereof in the compositions is contemplated. Supplementary active compounds can also be incorporated into the compositions.
• A pharmaceutical composition of the disclosure is formulated to be compatible with its intended route of administration. Examples of routes of administration include parenteral, e.g., intravenous, intradermal, subcutaneous, oral (e.g., inhalation), transdermal (i.e., topical), transmucosal, and rectal administration. Solutions or suspensions used for parenteral, intradermal, or subcutaneous application can include the following components: a sterile diluent such as water for injection, saline solution, fixed oils, polyethylene glycols, glycerine, propylene glycol or other synthetic solvents; antibacterial agents such as benzyl alcohol or methyl parabens; antioxidants such as ascorbic acid or sodium bisulfite; chelating agents such as ethylenediaminetetraacetic acid (EDTA); buffers such as acetates, citrates or phosphates, and agents for the adjustment of tonicity such as sodium chloride or dextrose. The pH can be adjusted with acids or bases, such as hydrochloric acid or sodium hydroxide. The parenteral preparation can be enclosed in ampoules, disposable syringes or multiple dose vials made of glass or plastic.
• Pharmaceutical compositions suitable for injectable use include sterile aqueous solutions (where water soluble) or dispersions and sterile powders for the extemporaneous preparation of sterile injectable solutions or dispersion. For intravenous administration, suitable carriers include physiological saline, bacteriostatic water, Cremophor EL™ (BASF, Parsippany, N.J.) or phosphate buffered saline (PBS). In all cases, the composition must be sterile and should be fluid to the extent that easy syringeability exists. It must be stable under the conditions of manufacture and storage and must be preserved against the contaminating action of microorganisms such as bacteria and fungi. The carrier can be a solvent or dispersion medium containing, for example, water, ethanol, polyol (for example, glycerol, propylene glycol, and liquid polyethylene glycol, and the like), and suitable mixtures thereof. The proper fluidity can be maintained, for example, by the use of a coating such as lecithin, by the maintenance of the required particle size in the case of dispersion and by the use of surfactants. Prevention of the action of microorganisms can be achieved by various antibacterial and antifungal agents, for example, parabens, chlorobutanol, phenol, ascorbic acid, thimerosal, and the like. In some embodiments, it will be desirable to include isotonic agents, for example, sugars, polyalcohols such as manitol, sorbitol, sodium chloride in the composition. Prolonged absorption of the injectable compositions can be brought about by including in the composition an agent that delays absorption, for example, aluminum monostearate and gelatin.
• Sterile injectable solutions can be prepared by incorporating the active compound in the required amount in an appropriate solvent with one or a combination of ingredients enumerated above, as required, followed by filtered sterilization. Generally, dispersions are prepared by incorporating the active compound into a sterile vehicle that contains a basic dispersion medium and the required other ingredients from those enumerated above. In the case of sterile powders for the preparation of sterile injectable solutions, methods of preparation are vacuum drying and freeze-drying that yields a powder of the active ingredient plus any additional desired ingredient from a previously sterile-filtered solution thereof.
• Oral compositions generally include an inert diluent or an edible carrier. They can be enclosed in gelatin capsules or compressed into tablets. For the purpose of oral therapeutic administration, the active compound can be incorporated with excipients and used in the form of tablets, troches, or capsules. Oral compositions can also be prepared using a fluid carrier for use as a mouthwash, wherein the compound in the fluid carrier is applied orally and swished and expectorated or swallowed. Pharmaceutically compatible binding agents, and/or adjuvant materials can be included as part of the composition. The tablets, pills, capsules, troches and the like can contain any of the following ingredients, or compounds of a similar nature: a binder such as microcrystalline cellulose, gum tragacanth or gelatin; an excipient such as starch or lactose, a disintegrating agent such as alginic acid, Primogel, or corn starch; a lubricant such as magnesium stearate or Sterotes; a glidant such as colloidal silicon dioxide; a sweetening agent such as sucrose or saccharin; or a flavoring agent such as peppermint, methyl salicylate, or orange flavoring.
• For administration by inhalation, the compounds are delivered in the form of an aerosol spray from pressured container or dispenser that contains a suitable propellant, e.g., a gas such as carbon dioxide, or a nebulizer.
• Systemic administration can also be by transmucosal or transdermal means. For transmucosal or transdermal administration, penetrants appropriate to the barrier to be permeated are used in the formulation. Such penetrants are generally known in the art, and include, for example, for transmucosal administration, detergents, bile salts, and fusidic acid derivatives. Transmucosal administration can be accomplished through the use of nasal sprays or suppositories. For transdermal administration, the active compounds are formulated into ointments, salves, gels, or creams as generally known in the art.
• The compounds can also be prepared in the form of suppositories (e.g., with conventional suppository bases such as cocoa butter and other glycerides) or retention enemas for rectal delivery.
• In one embodiment, the active compounds are prepared with carriers that will protect the compound against rapid elimination from the body, such as a controlled release formulation, including implants and microencapsulated delivery systems. Biodegradable, biocompatible polymers can be used, such as ethylene vinyl acetate, polyanhydrides, polyglycolic acid, collagen, polyorthoesters, and polylactic acid. Methods for preparation of such formulations will be apparent to those skilled in the art. The materials can also be obtained commercially from Alza Corporation and Nova Pharmaceuticals, Inc. Liposomal suspensions (including liposomes targeted to infected cells with monoclonal antibodies to viral antigens) can also be used as pharmaceutically acceptable carriers. These can be prepared according to methods known to those skilled in the art, for example, as described in U.S. Pat. No. 4,522,811.
• It is especially advantageous to formulate oral or parenteral compositions in dosage unit form for ease of administration and uniformity of dosage. Dosage unit form as used herein refers to physically discrete units suited as unitary dosages for the subject to be treated; each unit containing a predetermined quantity of active compound calculated to produce the desired therapeutic effect in association with the required pharmaceutical carrier. The specification for the dosage unit forms of the disclosure are dictated by and directly dependent on the unique characteristics of the active compound and the particular therapeutic effect to be achieved, and the limitations inherent in the art of compounding such an active compound for the treatment of individuals.
• The pharmaceutical compositions can be included in a container, pack, or dispenser together with instructions for administration.
• The invention will be further described in the following examples, which do not limit the scope of the invention described in the claims.
EXAMPLES Example 1. Generation of Mouse Antibodies of the Embodiments that Bind Human PD-1 and Block hPD-L1 and hPD-L2 Binding to Human PD-1
• This example demonstrates mouse antibodies of the disclosure that bind human PD-1 can be isolated from hybridomas derived from mouse immunization with recombinant human PD-1 protein, and that such binding can inhibit PD-1 binding to PDL1 and PDL2.
• Six NZBWF1/J female mice (Jackson Laboratories, Sacramento, Calif.; cat #100008) were immunized in the right flank with recombinant human PD-1 (Sino Biological, Beijing, P.R. China; cat # ABIN2181605) on days 0, 7 and 21. Serum was taken from immunized mice on day 28 and binding to HEK293-hPD-1 (cells transfected with an expression vector encoding human PD-1 (Origene, cat # SC117011)) was measured. All six mice showed positive binding. Splenocytes were isolated from mouse 1, 3 and 6 and fused with SP0 mouse B-cells; likewise splenocytes were isolated from mouse 2, 4 and 5 and fused with SP0 mouse B-cells, giving rise to pools of hybridomas, m136 and m245. The hybridoma pools, m136 and m245, arising from the two fusions were plated for single clones, and clonal culture supernatants were assayed for antibodies capable of binding to HEK293-hPD-1, and not to un-transfected HEK293, cells. Hybridoma clones expressing anti-PD-1 antibodies were chosen for further analysis.
• The sequences of the antibodies used in the studies presented herein are shown below:
• m136-M13-MHC723 mIgG1/K

• MHC723HC.1 Variable Heavy Chain

  Region Amino Acid Sequence:

  (SEQ ID NO: 1)

  EVKLVESGGGLVKPGGSLKLSCAASGFTFSGYAMSWVRQTPAKRLEWVAY

  ISNSGGNAHYPDSVKGRFTISRDNAKNTLYLQMSSLRSEDTAMYYCTRED

  YGTSPFVYWGQGTLVTVSA

  MHC723HC.1 Variable Heavy Chain

  Region Nucleic Acid Sequence:

  (SEQ ID NO: 2)

  GAAGTGAAGCTGGTGGAGTCTGGGGGAGGCTTAGTGAAACCTGGAGGGTC

  CCTGAAACTCTCCTGTGCAGCCTCTGGATTCACTTTCAGTGGCTATGCCA

  TGTCTTGGGTTCGCCAGACTCCGGCGAAGAGGCTGGAGTGGGTCGCATAC

  ATTAGTAATAGTGGTGGTAACGCCCACTATCCAGACAGTGTAAAGGGCCG

  ATTCACCATCTCCAGAGACAATGCCAAGAACACCCTATACCTGCAAATGA

  GCAGTCTGAGGTCTGAGGACACGGCCATGTATTACTGTACAAGAGAGGAC

  TACGGTACTAGTCCTTTTGTTTACTGGGGCCAAGGGACTCTGGTCACTGT

  CTCTGCA

  MHC723LC.3 Variable Light Chain

  Region Amino Acid Sequence:

  (SEQ ID NO: 3)

  DIVLTQSPASLAVSLGQRTTISCRASESVDNYGISFMNWFQQKPGQPPKL

  LIYAASNQGSGVPARFSGSGSGTDFSLNIHPMEEDDTAVYFCQQSKDVPW

  TFGGGTKLEIR

  MHC723LC.3 Variable Light Chain

  Region Nucleic Acid Sequence:

  (SEQ ID NO: 4)

  GACATTGTGCTGACCCAATCTCCAGCTTCTTTGGCTGTGTCTCTTGGGCA

  GAGGACCACCATCTCCTGCAGAGCCAGCGAAAGTGTTGATAATTATGGCA

  TTAGTTTTATGAACTGGTTCCAACAGAAACCAGGACAGCCACCCAAACTC

  CTCATCTATGCTGCATCCAACCAAGGATCCGGGGTCCCTGCCAGGTTTAG

  TGGCAGTGGGTCTGGGACAGACTTCAGCCTCAACATCCATCCTATGGAGG

  AGGATGATACTGCAGTGTATTTCTGTCAGCAAAGTAAGGACGTTCCGTGG

  ACGTTCGGTGGAGGCACCAAGCTGGAAATCAGAC

  
  m136-M19-MHC725 mIgG2b/K

• (SEQ ID NO: 5)
  MEIC725HC.2 Variable heavy chain region amino acid sequence:
  EVQLQQSGPELVKPGDSVKMSCKASGYTFTDYYMDWVKQSHGKSLEWIGYIYPKNGGSSYNQKF
  KGKATLTVDKSSSTAYMELHSLTSEDSAVYYCARKVVATDYWGQGTTLTVSS
  (SEQ ID NO: 6)
  MEIC725HC.2 Variable heavy chain region nucleic acid sequence:
  GAGGTCCAGCTGCAACAGTCTGGACCTGAGCTGGTGAAGCCTGGGGATTCAGTGAAGATGTCCT
  GCAAGGCTTCTGGCTACACATTCACTGACTACTACATGGACTGGGTGAAGCAGAGCCATGGAAA
  GAGCCITGAGIGGATTGGATATATTTATCCTAAAAATGGIGGITCCAGCTACAATCAGAAGTTC
  AAGGGCAAGGCCACATTGACTGTAGACAAGTCCTCCAGCACAGCCTACATGGAGCTCCACAGCC
  TGACATCTGAGGACTCTGCAGICTATTACTGTGCAAGAAAGGICGTAGCTACGGACTACTGGGG
  CCAAGGCACCACTCTCACAGTCTCCTCA
  (SEQ ID NO: 7)
  MEIC725LC.2 Variable light chain region amino acid sequence:

  DIVMSQSPSSLAVSVGEKVTMSCKSSQSLLYSSNQKNYLAWYQQKPGQSPKLLIFWASIRESGV
  PDRFTGSGSGTDFTLTISSVKAEDRAVYYCQQCDSYPWTFGGGTKLEIK
  (SEQ ID NO: 8)
  MIIC725LC.2 Variable light chain region nucleic acid sequence:
  GACATTGTGATGTCACAGTCTCCATCCTCCCTAGCTGTGTCAGTTGGAGAGAAGGTTACTATGA
  GCTGCAAGTCCAGTCAGAGCCTTTTATATAGTAGCAATCAAAAGAACTACTTGGCCTGGTACCA
  GCAGAAACCAGGGCAGTCTCCTAAACTGCTGATTTTCTGGGCATCTATTAGGGAATCTGGGGTC
  CCTGATCGCTTCACAGGCAGTGGATCTGGGACAGATTTCACTCTCACCATCAGCAGTGTGAAGG
  CTGAAGACCGGGCAGTTTATTACTGTCAGCAATGTGATAGCTATCCGTGGACGTTCGGTGGAGG
  CACCAAACTGGAAATCAAAC

  
  m245-M3-MHC728 mIgG2a/K

• (SEQ ID NO: 9)
  MIIC728HC.4 Variable heavy chain region amino acid sequence:
  EVKLVESGGGLVKPGGSLKLSCAASGFTFSNYAMSWVRQTPAKRLEWVAYISNGGGDTHYPDSL
  KGRFTVSRDNAKNTLYLQMSSLKSEDTAMYYCARENYGTSPFVYWGQGTLVTVSA
  (SEQ ID NO: 10)
  MIIC728HC.4 Variable heavy chain region nucleic acid sequence:
  GAAGTGAAGCTGGTGGAGTCTGGGGGAGGCTTAGTGAAACCTGGAGGGTCCCTGAAACTCTCCT
  GTGCAGCCTCTGGATTCACTTTCAGTAACTATGCCATGTCTTGGGTTCGCCAGACTCCGGCGAA
  GAGGCTGGAGTGGGTCGCATACATTAGTAATGGTGGTGGTGACACCCACTATCCAGACAGTTTA
  AAGGGCCGATTCACCGTCTCCAGAGACAATGCCAAGAACACCCTGTACCTACAAATGAGCAGTC
  TGAAGTCTGAGGACACGGCCATGTATTACTGTGCAAGAGAAAACTACGGTACTAGTCCCTTTGT
  TTACTGGGGCCAAGGGACTCTGGTCACTGTCTCTGCA
  (SEQ ID NO: 11)
  MIIC728LC.2Variable light chain region amino acid sequence:
  DIVLTQSPASLAVSLGQRATISCRASESVDNYGISFMNWFQQKPGQPPKLLIYAASNQGSGVPA
  RFSGSGSGTDFSLNIHPMEEDDTAMYFCQQSKDVPWTFGGGTKLEIK
  (SEQ ID NO: 12)
  MIIC728LC.2 Variable light chain region nucleic acid sequence:
  GACATTGTGCTGACCCAATCTCCAGCTTCTTTGGCTGTGTCTCTAGGGCAGAGGGCCACCATCT
  CCTGCAGAGCCAGCGAAAGTGTTGATAATTATGGCATTAGTTTTATGAACTGGTTCCAACAGAA
  ACCAGGACAGCCACCCAAACTCCTCATCTATGCTGCATCCAACCAAGGATCCGGGGTCCCTGCC
  AGGTTTAGTGGCAGTGGGTCTGGGACAGACTTCAGCCTCAACATCCATCCTATGGAGGAGGATG
  ATACTGCAATGTATTTCTGTCAGCAAAGTAAAGATGTTCCGTGGACGTTCGGTGGAGGCACCAA
  GCTGGAAATCAAAC

  
  m245-M5-MHC729 mIgG1/K

• (SEQ ID NO: 13)
  MEIC729HC.1 Variable heavy chain region amino acid sequence:
  EVQLVESGGGLVKSGGSLKLSCAHSGFSFSSYDMSWVRQTPAKRLEWVATISGGGRYTYYPDSV
  KGRFTISRDNAKNTLYLQMSGLRSEDTAMYYCASNYYGFDYWGQGTTLTVSS
  (SEQ ID NO: 14)
  MEIC729HC.1 Variable heavy chain region nucleic acid sequence:
  GAAGTGCAGCTGGTGGAGICIGGGGGAGGCTTAGTGAAGICTGGAGGGICCCTGAAACTCTCCT
  GTGCGCATTCTGGATTCAGTTTTAGTAGTTATGACATGTCTTGGGTTCGCCAGACTCCGGCGAA
  GAGGCTGGAGTGGGTCGCAACCATTAGTGGTGGTGGTCGTTACACCTACTATCCAGACAGTGTG
  AAGGGCCGATTCACCATCTCCAGAGACAATGCCAAGAACACCCTGTACCTGCAAATGAGCGGIC
  TGAGGTCTGAGGACACAGCCATGTATTACTGTGCAAGTAATTACTACGGTTTTGACTACTGGGG
  CCAAGGCACCACTCTCACAGTCTCTTCA
  (SEQ ID NO: 15)
  MEIC729LC.3 Variable light chain region amino acid sequence:
  DIVMTQSHKFMSTSVGDRVSITCKASQDVGTAVAWYQQKPGQSPKLLIYWASTRHTGVPDRFTG
  SGSGTDFTLTISNVQSEDLADYFCQQYSSYPWTFGGGTKLEIK
  (SEQ ID NO: 16)
  MEIC729LC.3 Variable light chain region nucleic acid sequence:
  GATATIGTGATGACCCAGICTCACAAATTCATGTCCACATCAGTAGGAGACAGGGICAGCATCA
  CCTGCAAGGCCAGTCAGGATGTGGGTACTGCTGTAGCCIGGTATCAACAGAAACCAGGGCAATC
  TCCTAAACTACTGATTTACTGGGCATCCACCCGGCACACTGGAGTCCCTGATCGCTICACGGGC
  AGTGGATCTGGGACAGATTTCACTCTCACCATTAGCAATGTGCAGTCTGAAGACTTGGCAGATT
  ATTTCTGTCAGCAATATAGCAGCTATCCGTGGACGTTCGGTGGAGGCACCAAGCTGGAAATCAA
  AC

• m136-M14-MHC724 mIgG2a/K

• (SEQ ID NO: 17)
  MEIC724HC.3 Variable heavy chain region amino acid sequence:
  KVMLVESGGDLVKPGGSLKLSCAASGFTFSSYGMSWVRQTPEKRLEWVATISGGGRDIYYADTV
  KGRFTISRDNAKNTLYLQMSSLRSEDTALYFCARLYLGFDYWGQGTTLTVSS
  (SEQ ID NO: 18)
  MEIC724HC.3 Variable heavy chain region nucleic acid sequence:
  AAAGTGATGCTGGTGGAGICTGGGGGAGACTTAGTGAAGCCTGGAGGGICCCTGAAACTCTCCT
  GTGCAGCCTCTGGATTCACTTTCAGTAGCTATGGCATGTCTTGGGTTCGCCAGACTCCGGAGAA
  GAGGCTGGAGTGGGTCGCAACCATTAGTGGTGGTGGTAGAGACATCTACTACGCAGACACTGTG
  AAGGGCCGATTCACCATCTCCAGAGACAATGCCAAGAACACCCTGTACCTACAAATGAGCAGTC
  TGAGGTCTGAGGACACGGCCTTGTATTTCTGTGCAAGGCTCTACCTGGGGTTTGACTACTGGGG
  CCAAGGCACCACTCTCACAGTCTCCTCA
  (SEQ ID NO: 19)
  MEIC724LC.1 Variable light chain region amino acid sequence:
  DIQMTQSPASQSASLGESVTITCLASQTIGTWLAWYQQKPGKSPQLLIYAATSLADGVPSRFSG
  SGSGTKFSFKISSLQAEDFVSYYCQQLYSIPWTFGGGTKLEIK
  (SEQ ID NO: 20)
  MEIC724LC.1 Variable light chain region nucleic acid sequence:
  GACATICAGATGACCCAGICTCCTGCCTCCCAGTCTGCATCTCTGGGAGAAAGTGTCACCATCA
  CATGCCTGGCAAGTCAGACCATTGGTACATGGITAGCATGGTATCAGCAGAAACCAGGGAAATC
  TCCTCAGCTCCTGATTTATGCTGCAACCAGCTTGGCAGATGGGGTCCCATCAAGGTTCAGTGGT
  AGTGGATCTGGCACAAAATTITCTTICAAGATCAGCAGCCTACAGGCTGAAGATTITGTAAGTT
  ATTACTGTCAACAACTITACAGTATTCCGTGGACATTCGGIGGAGGCACCAAGCTGGAAATCAA
  AC

• Binding of mouse antibodies m136-M13, m136-M19, m245-M3, m245-M5 and m136-M14 to human PD-1 was confirmed by ELISA (FIG. 1). Briefly, human PD-1-Fc (R and D systems, Minneapolis, Minn.) was adsorbed to the wells of a 96-well ELISA plate. Purified anti-PD-1 antibodies were applied to the plate in serial dilution and allowed to bind. Plates were washed with PBST (PBS, pH 7.2+0.05% Tween-20). Bound antibody was detected with an anti-mouse IgG-HRP conjugate (Sigma, St Louis, Mo.) and visualized with the chromogenic substrate TMB (Thermo Scientific, Rockford, Ill.). Plots were generated in Prizm (Sigma Plot) and the data were fit to a model of single site saturation binding. Anti-PD-1 antibodies nivolumab (NV1) and/or pembrolizumab (PM1) were used as positive controls in binding assays with anti-human IgG-HRP conjugate, FAb-specific (Sigma, St Louis, Mo.) for detection. The K_d for each antibody tested is shown in Table 10 below:

• TABLE 10
  Kd values for tested antibodies:

  	Clone	Kd, nM
  	245-M3	0.22
  	245-M5	0.34
  	136-M13	0.19
  	136-M19	0.23
  	136-M14	0.19
  	NV1 nivo	0.28
  	PM1 pembro	0.35

• Binding of mouse antibodies m136-M13, m136-M19, m245-M3, m245-M5 and m136-M14 to human PD-1 inhibited PD-1 binding to PDL1 and PDL2 in an inhibition ELISA assay (FIGS. 2-3). Inhibition ELISAs were performed as follows. Human PD-1-Fc (R and D systems, Minneapolis, Minn.) was adsorbed to the wells of a 96-well ELISA plate. Purified anti-PD-1 antibodies were applied to the plate in serial dilution in the presence of 2 nM biotinylated PD-L1 or 2 nM biotinylated PDL2. Binding of biotinylated PD-L1 and PD-L2 was detected by Pierce™ Streptavidin-poly HRP conjugate (Thermo Scientific, Rockford, Ill.) and visualized with TMB. Plots were generated in Prizm (Sigma Plot) and the data were fit to a model of single site competition binding and an IC₅₀ was determined. The IC₅₀ values for the M13 and M14 antibodies are shown in Table 11 below:

• TABLE 11
  IC50 values for antibodies tested

  IC50 (nM)	hPDL1/Fc	hPDL2/Fc
  M13	3.3	2
  M14	4.8	2.8

Example 2. Production and Testing of Humanized Anti-PD-1 Antibodies
• This example demonstrates that mouse antibodies of the disclosure that bind human PD-1 can be converted to humanized IgG antibodies that retain PD-1 binding and inhibition of PDL1 and PDL2 binding to PD-1.
• Variable domains of the mouse anti-PD-1 antibodies produced as described in Example 1 were humanized and expressed as full length hIgG4/hKappa antibodies. Fully human IgGs anti-PD-1 antibodies were expressed from transiently transfected HEK-293 cells and purified from the culture supernatant by Protein A chromatography.
• The sequences of the humanized antibodies used in the studies presented herein are shown below:

• (SEQ ID NO: 21)
  PD-1 A Hv Variable heavy chain region amino acid sequence:
  EVQLVESGGGLVQPGGSLRLSCAASGFTFSGYAMSWVRQAPGKGLEWVAYISNSGGNAHYADSV
  KGRFTISRDNSKNTLYLQMNSLRAEDTAVYYCTREDYGTSPFVYWGQGTLVTVSS
  (SEQ ID NO: 22)
  PD-1 A Hv Variable heavy chain region nucleic acid sequence:
  GAAGTGCAGCTGGTGGAATCTGGCGGCGGACTGGTGCAGCCTGGCGGATCTCTGAGACTGAGCT
  GTGCCGCCAGCGGCTTCACCTTTAGCGGCTACGCCATGAGCTGGGTGCGCCAGGCTCCTGGCAA
  AGGCCTGGAATGGGTGGCCTACATCAGCAACAGCGGCGGCAATGCCCACTACGCCGATAGCGTG
  AAGGGCCGGTTCACCATCAGCCGGGACAACAGCAAGAACACCCTGTACCTGCAGATGAACAGCC
  TGCGGGCCGAGGACACCGCCGTGTACTACTGCACCAGAGAGGACTACGGCACCAGCCCCTTCGT
  GTATTGGGGCCAGGGTACCCTCGTGACCGTCTCCTCA
  (SEQ ID NO: 23)
  PD-1 Ab Hv Variable heavy chain region amino acid sequence:
  EVQLVESGGGLVQPGGSLRLSCAASGFTFSGYAMSWVRQAPGKGLEWVSYISNSGGNAHYADSV
  KGRFTISRDNSKNTLYLQMNSLRAEDTAVYYCAKEDYGTSPFVYWGQGTLVTVSS
  (SEQ ID NO: 24)
  PD-1 Ab Hv Variable heavy chain region nucleic acid sequence:
  GAAGTGCAGCTGGTGGAATCTGGCGGCGGACTGGTGCAGCCTGGCGGATCTCTGAGACTGAGCT
  GTGCCGCCAGCGGCTTCACCTTTAGCGGCTACGCCATGAGCTGGGTGCGCCAGGCTCCTGGCAA
  AGGCCTGGAATGGGTGAGTTACATCAGCAACAGCGGCGGCAATGCCCACTACGCCGATAGCGTG
  AAGGGCCGGTTCACCATCAGCCGGGACAACAGCAAGAACACCCTGTACCTGCAGATGAACAGCC
  TGCGGGCCGAGGACACCGCCGTGTACTACTGCGCCAAGGAGGACTACGGCACCAGCCCCTTCGT
  GTATTGGGGCCAGGGTACCCTCGTGACCGTCTCCTCA
  (SEQ ID NO: 25)
  PD-1 Ae Hv Variable heavy chain region amino acid sequence:
  EVQLVESGGGLVQPGGSLRLSCAASGFTFSGYAMSWVRQAPGKGLEWVAYISNSGGNTHYADSV
  KGRFTISRDNSKNTLYLQMNSLRAEDTAVYYCAREDYGTSPFVYWGQGTLVTVSS
  (SEQ ID NO: 26)
  PD-1 Ae Hv Variable heavy chain region nucleic acid sequence:
  GAAGTGCAGCTGGTGGAATCTGGCGGCGGACTGGTGCAGCCTGGCGGATCTCTGAGACTGAGCT
  GTGCCGCCAGCGGCTTCACCTTTAGCGGCTACGCCATGAGCTGGGTGCGCCAGGCTCCTGGCAA
  AGGCCTGGAATGGGTGGCCTACATCAGCAACAGCGGCGGCAATACCCACTACGCCGATAGCGTG
  AAGGGCCGGTTCACCATCAGCCGGGACAACAGCAAGAACACCCTGTACCTGCAGATGAACAGCC
  TGCGGGCCGAGGACACCGCCGTGTACTACTGCGCCAGAGAGGACTACGGCACCAGCCCCTTCGT
  GTATTGGGGCCAGGGTACCCTCGTGACCGTCTCCTCA
  (SEQ ID NO: 27)
  PD-1 Af Hv Variable heavy chain region amino acid sequence:
  EVQLVESGGGLVQPGGSLRLSCAASGFTFSGYAMSWVRQAPGKGLEWVAYISNSGGNTHYADSL
  KGRFTVSRDNSKNTLYLQMNSLRAEDTAVYYCAREDYGTSPFVYWGQGTLVTVSS
  (SEQ ID NO: 28)
  PD-1 Af Hv Variable heavy chain region nucleic acid sequence:
  GAAGTGCAGCTGGTGGAATCTGGCGGCGGACTGGTGCAGCCTGGCGGATCTCTGAGACTGAGCT
  GTGCCGCCAGCGGCTTCACCTTTAGCGGCTACGCCATGAGCTGGGTGCGCCAGGCTCCTGGCAA
  AGGCCTGGAATGGGTGGCCTACATCAGCAACAGCGGCGGCAATACCCACTACGCCGATAGCCTG
  AAGGGCCGGTTCACCGTCAGCCGGGACAACAGCAAGAACACCCTGTACCTGCAGATGAACAGCC
  TGCGGGCCGAGGACACCGCCGTGTACTACTGCGCCAGAGAGGACTACGGCACCAGCCCCTTCGT
  GTATTGGGGCCAGGGTACCCTCGTGACCGTCTCCTCA
  (SEQ ID NO: 29)
  PD-1 Ba Hv Variable heavy chain region amino acid sequence:
  QVQLVQSGAEVKKPGASVKMSCKASGYTFTDYYMDWVRQAPGQGLEWIGYIYPKNGGSSYAQKF
  QGRATLTVDTSTSTAYMELSSLRSEDTAVYYCARKVVATDYWGQGTLLTVSS
  (SEQ ID NO: 30)
  PD-1 Ba Hv Variable heavy chain region nucleic acid sequence:
  CAGGIGCAGCTGGTGCAGICIGGCGCCGAAGTGAAGAAACCAGGCGCCAGCGTGAAGATGAGCT
  GCAAGGCCAGCGGCTACACCTTCACCGACTACTACATGGACTGGGTGCGCCAGGCCCCTGGACA
  GGGACTGGAATGGATCGGCTACATCTACCCCAAGAACGGCGGCAGCAGCTACGCCCAGAAGTTC
  CAGGGCAGAGCCACCCTGACCGTGGACACCAGCACAAGCACCGCCTACATGGAACTGAGCAGCC
  TGCGGAGCGAGGACACCGCCGTGTACTACTGCGCCAGAAAGGIGGTGGCCACAGACTACTGGGG
  CCAGGGTACCCTGCTGACCGTGTCTAGT
  (SEQ ID NO: 31)
  PD-1 Bb Hv Variable heavy chain region amino acid sequence:
  QVQLVQSGAEVKKPGASVKMSCKASGYTFTDYYMDWVRQAPGQGLEWIGYIYPKNGGSSYAQKF
  QGRATLTVDKSTSTAYMELSSLRSEDTAVYYCARKVVATDYWGQGTLLTVSS
  (SEQ ID NO: 32)
  PD-1 Bb Hv Variable heavy chain region nucleic acid sequence:
  CAGGIGCAGCTGGTGCAGICIGGCGCCGAAGTGAAGAAACCAGGCGCCAGCGTGAAGATGAGCT
  GCAAGGCCAGCGGCTACACCTTCACCGACTACTACATGGACTGGGTGCGCCAGGCCCCTGGACA
  GGGACTGGAATGGATCGGCTACATCTACCCCAAGAACGGCGGCAGCAGCTACGCCCAGAAGTTC
  CAGGGCAGAGCCACCCTGACCGTGGACAAGAGCACCAGCACCGCCTACATGGAACTGAGCAGCC
  TGCGGAGCGAGGACACCGCCGTGTACTACTGCGCCAGAAAGGIGGTGGCCACAGACTACTGGGG
  CCAGGGTACCCTGCTGACCGTGTCTAGT
  (SEQ ID NO: 33)
  PD-1 C Hy Variable heavy chain region amino acid sequence:
  EVQLVESGGGLVQPGGSLRLSCAASGFTFSNYAMSWVRQAPGKGLEWVAYISNGGGDTHYADSL
  KGRFTVSRDNSKNTLYLQMNSLRAEDTAVYYCARENYGTSPFVYWGQGTLVTVSS
  (SEQ ID NO: 34)
  PD-1 C Hy Variable heavy chain region nucleic acid sequence:
  GAAGTGCAGCTGGTGGAATCTGGCGGCGGACTGGTGCAGCCTGGCGGATCTCTGAGACTGAGCT
  GTGCCGCCAGCGGCTICACCTICAGCAACTACGCCATGAGCTGGGTGCGCCAGGCCCCTGGAAA
  AGGCCTGGAATGGGTGGCCTACATCAGCAACGGCGGAGGCGATACCCACTACGCCGATAGCCTG
  AAGGGCCGGTTCACCGTGTCCAGAGACAACAGCAAGAACACCCTGTACCTGCAGATGAACAGCC
  TGCGGGCCGAGGACACCGCCGTGTACTATTGCGCCAGAGAGAACTACGGCACCAGCCCCTTCGT
  GTACTGGGGCCAGGGTACCCTCGTGACCGTGTCCTCT
  (SEQ ID NO: 35)
  PD-1 Ca Hy Variable heavy chain region amino acid sequence:
  EVQLVESGGGLVQPGGSLRLSCAASGFTFSNYAMSWVRQAPGKGLEWVAYISNQGGDTHYADSL
  KGRFTVSRDNSKNTLYLQMNSLRAEDTAVYYCARENYGTSPFVYWGQGTLVTVSS
  (SEQ ID NO: 36)
  PD-1 Ca Hy Variable heavy chain region nucleic acid sequence:
  GAAGTGCAGCTGGTGGAATCTGGCGGCGGACTGGTGCAGCCTGGCGGATCTCTGAGACTGAGCT
  GTGCCGCCAGCGGCTICACCTICAGCAACTACGCCATGAGCTGGGTGCGCCAGGCCCCTGGAAA
  AGGCCTGGAATGGGTGGCCTACATCAGCCAAGGCGGAGGCGATACCCACTACGCCGATAGCCTG
  AAGGGCCGGTTCACCGTGTCCAGAGACAACAGCAAGAACACCCTGTACCTGCAGATGAACAGCC
  TGCGGGCCGAGGACACCGCCGTGTACTATTGCGCCAGAGAGAACTACGGCACCAGCCCCTTCGT
  GTACTGGGGCCAGGGTACCCTCGTGACCGTGTCCTCT
  (SQ ID NO: 37)
  PD-1 D Hv Variable heavy chain region amino acid sequence:
  EVQLVESGGGLVQPGGSLRLSCAHSGFSFSSYDMSWVRQAPGKGLEWVATISGGGRYTYYADSV
  KGRFTISRDNSKNTLYLQMNSLRAEDTAVYYCASNYYGFDYWGQGTLLTVSS
  (SEQ ID NO: 38)
  PD-1 D Hv Variable heavy chain region nucleic acid sequence:
  GAAGTGCAGCTGGTGGAATCTGGCGGCGGACTGGTGCAGCCTGGCGGATCTCTGAGACTGAGCT
  GTGCCCACAGCGGCTTCAGCTTCAGCAGCTACGACATGAGCTGGGTGCGCCAGGCCCCTGGCAA
  AGGACTGGAATGGGTGGCCACAATCAGCGGCGGAGGCCGGTACACCTACTACGCCGATAGCGTG
  AAGGGCCGGTTCACCATCAGCCGGGACAACAGCAAGAACACCCTGTACCTGCAGATGAACAGCC
  TGCGGGCCGAGGACACCGCCGTGTACTACTGCGCCAGCAACTACTACGGCTTCGACTACTGGGG
  CCAGGGTACCCTGCTGACCGTGTCATCT
  (SEQ ID NO: 39)
  PD-1 1.0 Lv Variable light chain region amino acid sequence:
  DIQLTQSPSSLSASVGDRVTITCRASESVDNYGISFMNWFQQKPGKAPKLLIYAASNQGSGVPS
  RFSGSGSGTDFTLTISSMQPEDFATYYCQQSKDVPWTFGQGTKLEIK
  (SEQ ID NO: 40)
  PD-1 1.0 Lv Variable light chain region nucleic acid sequence:
  GACATCCAGCTGACCCAGAGCCCTAGCAGCCTGTCTGCCAGCGTGGGCGACAGAGTGACCATCA
  CCTGTAGAGCCAGCGAGAGCGTGGACAACTACGGCATCAGCTTCATGAACTGGTTCCAGCAGAA
  GCCCGGCAAGGCCCCCAAGCTGCTGATCTACGCCGCCAGCAATCAGGGCAGCGGCGTGCCAAGC
  AGATTTTCCGGCTCTGGCAGCGGCACCGACTTCACCCTGACCATCAGCAGCATGCAGCCCGAGG
  ACTTCGCCACCTACTACTGCCAGCAGAGCAAGGACGTGCCCTGGACCTTTGGCCAGGGTACCAA
  GCTGGAAATCAAG
  (SEQ ID NO: 41)
  PD-1 1.1 Lv Variable light chain region amino acid sequence:
  DIQLTQSPSSLSVSVGDRATITCRASESVDNYGISFMNWFQQKPGKAPKLLIYAASNQGSGVPS
  RFSGSGSGTDFTLTISSMQPEDFATYYCQQSKDVPWTFGQGTKLEIK
  (SEQ ID NO: 42)
  PD-1 1.1 Lv Variable light chain region nucleic acid sequence:
  GACATCCAGCTGACCCAGAGCCCTAGCAGCCTGTCCGTGTCCGTGGGCGACAGAGCCACCATCA
  CCTGTAGAGCCAGCGAGAGCGTGGACAACTACGGCATCAGCTTCATGAACTGGTTCCAGCAGAA
  GCCCGGCAAGGCCCCCAAGCTGCTGATCTACGCCGCCAGCAATCAGGGCAGCGGCGTGCCAAGC
  AGATTTTCCGGCTCTGGCAGCGGCACCGACTTCACCCTGACCATCAGCAGCATGCAGCCCGAGG
  ACTTCGCCACCTACTACTGCCAGCAGAGCAAGGACGTGCCCTGGACCTTTGGCCAGGGTACCAA
  GCTGGAAATCAAG
  (SEQ ID NO: 43)
  PD-1 1.2 Lv Variable light chain region amino acid sequence:
  DIQLTQSPSSLSASVGDRVTITCRASESVDQYGISFMNWFQQKPGKAPKLLIYAASNQGSGVPS
  RFSGSGSGTDFTLTISSMQPEDFATYYCQQSKDVPWFGQGTKLEIK
  (SEQ ID NO: 44)
  PD-1 1.2 Lv Variable light chain region nucleic acid sequence:
  GACATCCAGCTGACCCAGAGCCCTAGCAGCCTGTCTGCCAGCGTGGGCGACAGAGTGACCATCA
  CCTGTAGAGCCAGCGAGAGCGTGGACCAATACGGCATCAGCTTCATGAACTGGTTCCAGCAGAA
  GCCCGGCAAGGCCCCCAAGCTGCTGATCTACGCCGCCAGCAATCAGGGCAGCGGCGTGCCAAGC
  AGATTTTCCGGCTCTGGCAGCGGCACCGACTTCACCCTGACCATCAGCAGCATGCAGCCCGAGG
  ACTTCGCCACCTACTACTGCCAGCAGAGCAAGGACGTGCCCTGGACCTTTGGCCAGGGTACCAA
  GCTGGAAATCAAG
  (SEQ ID NO: 45)
  PD-1 1.4 Lv Variable light chain region amino acid sequence:
  DIQLTQSPSSLSASVGDRVTITCRASESVDSYGISFMNWFQQKPGKAPKLLIYAASNQGSGVPS
  RFSGSGSGTDFTLTISSMQPEDFATYYCQQSKDVPWTFGQGTKLEIK
  (SEQ ID NO: 46)
  PD-1 1.4 Lv Variable light chain region nucleic acid sequence:
  GACATCCAGCTGACCCAGAGCCCTAGCAGCCTGTCTGCCAGCGTGGGCGACAGAGTGACCATCA
  CCTGTAGAGCCAGCGAGAGCGTGGACAGTTACGGCATCAGCTTCATGAACTGGTTCCAGCAGAA
  GCCCGGCAAGGCCCCCAAGCTGCTGATCTACGCCGCCAGCAATCAGGGCAGCGGCGTGCCAAGC
  AGATTTTCCGGCTCTGGCAGCGGCACCGACTTCACCCTGACCATCAGCAGCATGCAGCCCGAGG
  ACTTCGCCACCTACTACTGCCAGCAGAGCAAGGACGTGCCCTGGACCTTTGGCCAGGGTACCAA
  GCTGGAAATCAAG
  (SEQ ID NO: 47)
  PD-1 1.5 Lv Variable light chain region amino acid sequence:
  DIQLTQSPSSLSASVGDRVTITCRASESVDAYGISFMNWFQQKPGKAPKLLIYAASNQGSGVPS
  RFSGSGSGTDFTLTISSMQPEDFATYYCQQSKDVPWTFGQGTKLEIK
  (SEQ ID NO: 48)
  PD-1 1.5 Lv Variable light chain region nucleic acid sequence:
  GACATCCAGCTGACCCAGAGCCCTAGCAGCCTGTCTGCCAGCGTGGGCGACAGAGTGACCATCA
  CCTGTAGAGCCAGCGAGAGCGTGGACGCTTACGGCATCAGCTTCATGAACTGGTTCCAGCAGAA
  GCCCGGCAAGGCCCCCAAGCTGCTGATCTACGCCGCCAGCAATCAGGGCAGCGGCGTGCCAAGC
  AGATTTTCCGGCTCTGGCAGCGGCACCGACTTCACCCTGACCATCAGCAGCATGCAGCCCGAGG
  ACTTCGCCACCTACTACTGCCAGCAGAGCAAGGACGTGCCCTGGACCTTTGGCCAGGGTACCAA
  GCTGGAAATCAAG
  (SEQ ID NO: 49)
  PD-1 1.6 Lv Variable light chain region amino acid sequence:
  DIQLTQSPSSLSASVGDRVTITCRASESVDNYGISFMNWFQQKPGKAPKLLIYAASDQGSGVPS
  RFSGSGSGTDFTLTISSMQPEDFATYYCQQSKDVPWTFGQGTKLEIK
  (SEQ ID NO: 50)
  PD-1 1.6 Lv Variable light chain region nucleic acid sequence:
  GACATCCAGCTGACCCAGAGCCCTAGCAGCCTGTCTGCCAGCGTGGGCGACAGAGTGACCATCA
  CCTGTAGAGCCAGCGAGAGCGTGGACAACTACGGCATCAGCTTCATGAACTGGTTCCAGCAGAA
  GCCCGGCAAGGCCCCCAAGCTGCTGATCTACGCCGCCAGCGATCAGGGCAGCGGCGTGCCAAGC
  AGATTTTCCGGCTCTGGCAGCGGCACCGACTTCACCCTGACCATCAGCAGCATGCAGCCCGAGG
  ACTTCGCCACCTACTACTGCCAGCAGAGCAAGGACGTGCCCTGGACCTTTGGCCAGGGTACCAA
  GCTGGAAATCAAG
  (SEQ ID NO: 51)
  PD-1 1.7 Lv Variable light chain region amino acid sequence:
  DIQLTQSPSSLSVSVGDRATITCRASESVDAYGISFMNWFQQKPGKAPKLLIYAASNQGSGVPS
  RFSGSGSGTDFTLTISSMQPEDFATYYCQQSKDVPWTFGQGTKLEIK
  (SEQ ID NO: 52)
  PD-1 1.7 Lv Variable light chain region nucleic acid sequence:
  GACATCCAGCTGACCCAGAGCCCTAGCAGCCTGTCCGTGTCCGTGGGCGACAGAGCCACCATCA
  CCTGTAGAGCCAGCGAGAGCGTGGACGCTTACGGCATCAGCTTCATGAACTGGTTCCAGCAGAA
  GCCCGGCAAGGCCCCCAAGCTGCTGATCTACGCCGCCAGCAATCAGGGCAGCGGCGTGCCAAGC
  AGATTTTCCGGCTCTGGCAGCGGCACCGACTTCACCCTGACCATCAGCAGCATGCAGCCCGAGG
  ACTTCGCCACCTACTACTGCCAGCAGAGCAAGGACGTGCCCTGGACCTTTGGCCAGGGTACCAA
  GCTGGAAATCAAG
  (SEQ ID NO: 53)
  PD-1 1.9 Lv Variable light chain region amino acid sequence:
  DIQLTQSPSSLSASVGDRVTITCRASESVDAYGISFMNWFQQKPGKAPKLLIYAASNQGSGVPS
  RFSGSGSGTDFTLTISSMQPEDFATYYCQQSKDVPWTFGQGTKVEIK
  (SEQ ID NO: 54)
  PD-1 1.9 Lv Variable light chain region nucleic acid sequence:
  GACATCCAGCTGACCCAGAGCCCTAGCAGCCTGTCTGCCAGCGTGGGCGACAGAGTGACCATCA
  CCTGTAGAGCCAGCGAGAGCGTGGACGCTTACGGCATCAGCTTCATGAACTGGTTCCAGCAGAA
  GCCCGGCAAGGCCCCCAAGCTGCTGATCTACGCCGCCAGCAATCAGGGCAGCGGCGTGCCAAGC
  AGATTTTCCGGCTCTGGCAGCGGCACCGACTTCACCCTGACCATCAGCAGCATGCAGCCCGAGG
  ACTTCGCCACCTACTACTGCCAGCAGAGCAAGGACGTGCCCTGGACCTTTGGCCAGGGTACCAA
  GGTGGAAATCAAG
  (SEQ ID NO: 55)
  PD-1 1.10 Lv Variable light chain region amino acid sequence:
  DIQLTQSPSSLSASVGDRVTITCRASESVDAYGISFMNWFQQKPGKAPKLLIYAASNQGSGVPS
  RFSGSGSGTDFTLTISSMQPEDFATYYCQQSKDVPYTFGQGTKLEIK
  (SEQ ID NO: 56)
  PD-1 1.10 Lv Variable light chain region nucleic acid sequence:
  GACATCCAGCTGACCCAGAGCCCTAGCAGCCTGTCTGCCAGCGTGGGCGACAGAGTGACCATCA
  CCTGTAGAGCCAGCGAGAGCGTGGACGCTTACGGCATCAGCTTCATGAACTGGTTCCAGCAGAA
  GCCCGGCAAGGCCCCCAAGCTGCTGATCTACGCCGCCAGCAATCAGGGCAGCGGCGTGCCAAGC
  AGATTTTCCGGCTCTGGCAGCGGCACCGACTTCACCCTGACCATCAGCAGCATGCAGCCCGAGG
  ACTTCGCCACCTACTACTGCCAGCAGAGCAAGGACGTGCCCTACACCTTTGGCCAGGGTACCAA
  GCTGGAAATCAAG
  (SEQ ID NO: 57)
  PD-1 2 Lv Variable light chain region amino acid sequence:
  DIQMTQSPSSLSASVGDRVTMTCKSSQSLLYSSNQKNYLAWYQQKPGKAPKLLIFWASIRESGV
  PSRFSGSGSGTDFTLTISSVQPEDFATYYCQQSDSYPWTFGQGTKLEIK
  (SEQ ID NO: 58)
  PD-1 2 Lv Variable light chain region nucleic acid sequence:
  GACATCCAGATGACCCAGAGCCCCAGCAGCCTGTCTGCCAGCGTGGGCGATAGAGTGACCATGA
  CCTGCAAGAGCAGCCAGAGCCTGCTGTACTCCAGCAACCAGAAGAACTACCTGGCCTGGTATCA
  GCAGAAGCCCGGCAAGGCCCCCAAGCTGCTGATCTTCTGGGCCAGCATCCGGGAAAGCGGCGTG
  CCCAGCAGATTTTCTGGCTCTGGCAGCGGCACCGACTTCACCCTGACAATCAGCAGCGTGCAGC
  CCGAGGACTTCGCCACCTACTACTGCCAGCAGAGCGACAGCTACCCCTGGACCTTTGGCCAGGG
  TACCAAGCTGGAAATCAAG
  (SEQ ID NO: 59)
  PD-1 4 Lv Variable light chain region amino acid sequence:
  DIQMTQSPSSLSASVGDRVTITCKASQDVGTAVAWYQQKPGKAPKLLIYWASTRHTGVPSRFSG
  SGSGTDFTLTISSVQPEDFATYYCQQYSSYPWTFGQGTKLEIK
  (SEQ ID NO: 60)
  PD-1 4 Lv Variable light chain region nucleic acid sequence:
  GACATCCAGATGACCCAGAGCCCCAGCAGCCTGTCTGCCAGCGTGGGCGACAGAGTGACCATCA
  CATGCAAGGCCAGCCAGGACGTGGGAACAGCCGTGGCCTGGTATCAGCAGAAGCCTGGCAAGGC
  CCCCAAGCTGCTGATCTACTGGGCCAGCACCAGACACACCGGCGTGCCCAGCAGATTTTCTGGC
  AGCGGCTCCGGCACCGACTTCACCCTGACAATCAGCAGCGTGCAGCCCGAGGACTTCGCCACCT
  ACTACTGCCAGCAGTACAGCAGCTACCCCTGGACCTTTGGCCAGGGTACCAAGCTGGAAATCAA
  G
  (SEQ ID NO: 61)
  Kappa constant region amino acid sequence:
  RTVAAPSVFIFPPSDEQLKSGTASVVCLLNNFYPREAKVQWKVDNALQSGNSQESVTEQDSKDS
  TYSLSSTLTLSKADYEKHKVYACEVTHQGLSSPVTKSFNRGEC
  (SEQ ID NO: 62)
  Kappa constant region nucleic acid sequence:
  CGTACGGIGGCTGCACCATCTGICTICATCTICCCGCCATCTGATGAGCAGTTGAAATCTGGAA
  CTGCCTCTGTTGTGTGCCTGCTGAATAACTICTATCCCAGAGAGGCCAAAGTACAGTGGAAGGT
  GGATAACGCCCTCCAATCGGGTAACTCCCAGGAGAGTGTCACAGAGCAGGACAGCAAGGACAGC
  ACCTACAGCCICAGCAGCACCCTGACGCTGAGCAAAGCAGACTACGAGAAACACAAAGICTACG
  CCTGCGAAGTCACCCATCAGGGCCTGAGCTCGCCCGTCACAAAGAGCTICAACAGGGGAGAGTG
  T
  (SEQ ID NO: 63)
  hIgG4 S228P amino acid sequence:
  ASTKGPSVFPLAPCSRSTSESTAALGCLVKDYFPEPVTVSWNSGALTSGVHTFPAVLQSSGLYS
  LSSVVTVPSSSLGTKTYTCNVDHKPSNTKVDKRVESKYGPPCPPCPAPEFLGGPSVFLFPPKPK
  DTLMISRTPEVTCVVVDVSQEDPEVQFNWYVDGVEVHNAKTKPREEQFNSTYRVVSVLTVLHQD
  WLNGKEYKCKVSNKGLPSSIEKTISKAKGQPREPQVYTLPPSQEEMTKNQVSLTCLVKGFYPSD
  IAVEWESNGQPENNYKTTPPVLDSDGSFFLYSRLTVDKSRWQEGNVFSCSVMHEALHNHYTQKS
  LSLSLGK
  (SEQ ID NO: 64)
  hIgG4 S228P nucleic acid sequence:
  GCTAGCACCAAGGGCCCATCGGTCTTCCCCCTGGCACCCTGTAGCAGAAGCACCAGCGAGTCTA
  CAGCGGCCCTGGGCTGCCTGGTCAAGGACTACTTCCCCGAACCGGTGACGGTGTCGTGGAACTC
  AGGCGCCCTGACCAGCGGCGTGCACACCTTCCCGGCTGTCCTACAGTCCTCAGGACTCTACTCC
  CTCAGCAGCGTGGTGACCGTGCCCTCCAGCAGCTTGGGCACCAAGACCTACACCTGTAACGTGG
  ACCACAAGCCCAGCAACACCAAGGTGGACAAGCGGGTGGAATCTAAGTACGGCCCTCCCTGCCC
  TCCTTGCCCAGCCCCTGAATTICTGGGGGGACCGTCAGICTICCTCTICCCCCCAAAACCCAAG
  GACACCCTCATGATCTCCCGGACCCCTGAGGTCACATGCGTGGTGGTGGACGTGAGCCAGGAAG
  ACCCTGAGGICCAGTTCAACTGGTACGTGGACGGCGTGGAGGTGCATAATGCCAAGACAAAGCC
  GCGGGAGGAGCAGTTCAACAGCACGTACCGTGTGGTCAGCGTCCTCACCGTCCTGCACCAGGAC
  TGGCTGAATGGCAAGGAGTACAAGTGCAAGGICTCCAACAAAGGCCTGCCCAGCTCCATCGAGA
  AAACCATCTCCAAAGCCAAAGGGCAGCCCCGAGAACCACAGGIGTACACCCTGCCCCCATCCCA
  GGAGGAGATGACCAAGAACCAGGICAGCCTGACCTGCCTGGICAAAGGCTICTATCCCAGCGAC
  ATCGCCGTGGAGTGGGAGAGCAATGGGCAGCCGGAGAACAACTACAAGACCACGCCTCCCGTGC
  TGGACTCCGACGGCTCCTTCTTCCTCTACAGCAGACTCACCGTGGACAAGAGCAGGTGGCAGGA
  AGGGAACGTCTTCTCATGCTCCGTGATGCATGAGGCTCTGCACAACCACTACACGCAGAAGAGC
  CTCTCCCTGTCTCTGGGTAAA

• These variable heavy chain regions (VH) and variable light chain regions (VL) can be used in a variety of combinations to produce anti-PD-1 antibodies of the disclosure. For example, the antibody referred to herein as A1.0 includes the VH sequence of SEQ ID NO: 21 and the VL sequence of SEQ ID NO: 39, the A1.5 antibody includes the VH sequence of SEQ ID NO: 21 and the VL sequence of SEQ ID NO: 47; the antibody referred to herein as C1.1 includes the VH sequence of SEQ ID NO: 33 and the VL sequence of SEQ ID NO: 41, and so on.
• As shown in FIGS. 4-5, humanized anti-PD-1 antibodies bound to hPD-1 in a standard ELISA in a manner similar to that of nivolumab and/or pembrolizumab, and binding of the humanized antibodies inhibited the binding of PD-1 to PDL1 and PDL2 (FIGS. 6-9) in inhibition ELISAs. ELISAs were performed as follows. For hPD-1 binding ELISAs, human PD-1-Fc (R and D systems, Minneapolis, Minn.) was adsorbed to the wells of a 96-well ELISA plate. Purified anti-PD-1 antibodies were applied to the plate in serial dilution and allowed to bind. Bound antibody was detected with an anti-human IgG-HRP conjugate (FAb-specific) (Sigma, St Louis, Mo.) and visualized with the chromogenic substrate TMB (Thermo Scientific, Rockford, Ill.). Plots were generated in Prizm (Sigma Plot) and the data were fit to a model of single site saturation binding. For ligand inhibition ELISAs, human PD-1-Fc (R and D systems, Minneapolis, Minn.) was adsorbed to the wells of a 96-well ELISA plate. Purified anti-PD-1 antibodies were applied to the plate in serial dilution in the presence of 2 nM biotinylated hPD-L1 or 2 nM biotinylated hPD-L2. Pierce™ Streptavidin-poly HRP conjugate (Thermo Scientific, Rockford, Ill.) and visualized with TMB. Plots were generated in Prizm (Sigma Plot) and the data were fit to a model of single site competition binding and an IC₅₀ was determined.
Example 3: Anti-PD-1 Antibodies Shows Specificity in Binding
• Example 3 shows that humanized anti-PD-1 antibody groups A1 and C1 of the disclosure bind specifically to hPD-1 by plate ELISA.
• The binding of anti-PD-1 antibody A1.5 of the disclosure was highly specific to hPD-1-Fc in a standard ELISA against a panel of numerous human and mouse proteins (FIG. 10). Binding of anti-PD-1 A1.5 was detected with an anti-human IgG-HRP conjugate (FAb-specific) (Sigma, St Louis, Mo.) and visualized with the chromogenic substrate TMB (Thermo Scientific, Rockford, Ill.). Plots were generated in Prizm (Sigma Plot) and the data were fit to a model of single site saturation binding.
Example 4: Anti-PD-1 Epitope Binding
• This example compares the epitopes bound by humanized anti-PD-1 antibodies of the disclosure, nivolumab, and pembrolizumab.
• Nivolumab and pembrolizumab anti-PD-1 antibodies each bind human PD-1 and such binding by each inhibits the binding of PD-1 to PDL1 and PDL2. To map the epitopes of humanized groups A1 and C1 antibodies of the disclosure, anti-PD-1 inhibition ELISAs were performed, and compared with nivolumab and pembrolizumab inhibition. Dilution series of nivolumab, pembrolizumab, A1 and C1 antibodies were incubated in the presence of biotinylated nivolumab FAb or biotinylated pembrolizumab FAb at a concentration of 0.3 nM in a standard plate ELISA format with hPD-1-Fc (R & D systems, Minneapolis, Minn.). Binding of biotinylated FAb was detected by Pierce™ Streptavidin-poly HRP conjugate (Thermo Scientific, Rockford, Ill.) and visualized with TMB (Thermo Scientific, Rockford Ill.) and 1N HCl. Antibodies belonging to the A1 and C1 groups of the disclosure blocked biotinylated Pembrolizumab FAb binding to PD-1 similarly to Pembrolizumab antibody and more completely than nivolumab antibody (FIG. 11A). The same A1 and C1 antibodies of the disclosure blocked biotinylated nivolumab binding similarly to nivolumab antibody and more completely than pembrolizumab antibody (FIG. 11B). The data in FIGS. 11A and 11B show that A1 and C1 antibodies of the disclosure completely block both nivolumab and pembrolizumab, whereas nivolumab and pembrolizumab incompletely block each other.
Example 5: Anti-PD-1 A1.5 Enhances CMV-Stimulated Cytokine Secretion by PBMCs from a CMV-Positive Donor
• In this example, peripheral blood mononuclear cells from a CMV-positive donor were incubated in the presence of CMV viral lysate and anti-PD-1 antibodies of the disclosure to assess the effect of such anti-PD-1 antibodies on interferon gamma (IFN-gamma, IFNg, IFN-g, IFNγ, or IFN-γ) cytokine secretion.
• PBMCs from a CMV-positive donor (Hemacare) were plated at 2×10⁵ cells/well in the presence of CMV viral lysate (Astarte) and either anti-PD-1 antibody A1.5 of the disclosure or a hIgG4 isotype control antibody. After four days, supernatant was removed from each well, and IFN-gamma levels were assayed using IFN-gamma ELISA kit (Life Technologies, Carlsbad, Calif.) (FIG. 12). Anti-PD-1 antibody A1.5 increased CMV-stimulated IFN-gamma secretion compared with control hIgG4 and with potency similar to anti-PD-1 nivolumab and pembrolizumab antibodies.
Example 6: Anti-PD-1 Antibodies Bind to Monomeric hPD-1 with High Affinity and Slow Dissociation Kinetics
• In this example, humanized anti-PD-1 antibodies of the disclosure are shown to bind with high affinity and slow dissociation to monomeric PD-1.
• Activatable antibodies can be activated singly, creating a monovalent binding moiety, or doubly, creating a bivalent binding moiety. Single-arm activation of antibodies with differing avidities can favor binding and biological activity of activatable antibodies with higher monovalent affinities. Anti-PD-1 antibodies A1.5 and Bba2 of the disclosure, as well as nivolumab and pembrolizumab were immobilized at equivalent densities on Forte-Bio Octet BioLayer Inferometry (Pall ForteBio, Menlo Park, Calif.) sensors and allowed to bind to a serial dilution of human PD-1-His (R & D systems, Minneapolis, Minn.) in solution. Kinetic analysis was performed with ForteBio Data Analysis software. Results (FIG. 13) show PD-1 antibodies of the disclosure bind monomeric PD-1 with similar or higher affinities and similar or slower dissociation constants than nivolumab or pembrolizumab.
Example 7: Activatable Anti-PD-1 M13/A1.4/A1.5 Antibody Masking Moieties
• This example describes identification of masking moieties (MM) that reduce binding of anti-PD-1 antibodies of the disclosure to their target.
• Anti-PD-1 antibodies m136-M13, A1.4 and A1.5 were used to screen libraries using a method similar to that described in PCT International Publication Number WO 2010/081173, published 15 Jul. 2010. The screening consisted of one round of MACS and five rounds of FACS sorting. For the initial MACS, approximately 2×10¹¹ cells were incubated with m136-M13 antibody at a concentration of 100 nM, and 6×10⁶ binders were collected using Protein-G Dynabeads (Invitrogen). FACS rounds were conducted labeling cells with DyLight 650 (Thermo-Fisher) labeled m136-M19 antibody for FACS rounds 1-4 as follows: 100 nM FACS round 1 (F1), 10 nM FACS round 2 (F2), 2 nM FACS round 3 (F3) and 1 nM FACS round 4 (F4), with increasingly small percentages of binders as assessed by fluorescence collected at each round. For FACS round 5 (F5), cells were labeled with 1 nM DyLight 650 labeled A1.5 antibody and the brightest 0.2-4% of cells were collected. Individual peptide clones from F3, F4 and F5 were identified by sequence analysis and subsequently verified for their ability to bind DyLight-650 A1.4 or DyLight-650 A1.5.
• The sequences of the anti-PD-1 m136-M13, A1.4 and A1.5 masking moieties are listed in Table 12 (masking moiety PD001 is also referred to in the disclosure as PD01 and/or PD-01; masking moiety PD002 is also referred to herein as PD02 and/or PD-02, and so on):

• 	TABLE 12
  	Masking Moieties

  	Mask	Amino Acid Sequence	SEQ ID NO:
  	PD001	AMSGCSWSAFCPYLA	66
  	PD002	DVNCAIWYSVCTTVP	67
  	PD003	LVCPLYALSSGVCMG	68
  	PD004	SVNCRIWSAVCAGYE	69
  	PD005	MLVCSLQPTAMCERV	70
  	PD006	APRCYMFASYCKSQY	71
  	PD007	VGPCELTPKPVCNTY	72
  	PD008	ETCNQYERSSGLCFA	73
  	PD009	APRTCYTYQCSSFYT	74
  	PD010	GLCSWYLSSSGLCVD	75
  	PD011	VPWCQLTPRVMCMWA	76
  	PD012	NWLDCQFYSECSVYG	77
  	PD013	SCPLYVMSSFGGCWD	78
  	PD014	MSHCWMFSSSCDGVK	79
  	PD015	VSYCTWLIEVTCLRG	80
  	PD016	VLCAAYALSSGICGG	81
  	PD017	TTCNLYQQSSMFCNA	82
  	PD018	APRCYMFASYCKSQY	83
  	PD019	PCDQNPYFYPYVCHA	84
  	PD020	SVCPMYALSSMLCGA	85
  	PD021	LSVECYVFSRCSSLP	86
  	PD022	FYCTYLVSLTCHPQ	87
  	PD023	SMAGCQWSSFCVQRD	88
  	PD024	IYSCYMFASRCTSDK	89
  	PD025	SRCSVYEVSSGLCDW	90
  	PD026	GMCSAYAYSSKLCTI	91
  	PD027	MTTNTCNLLCQQFLT	92
  	PD028	FQPCLMFASSCFTSK	93
  	PD029	WNCHPAGVGPVFCEV	94
  	PD030	ALCSMYLASSGLCNK	95
  	PD031	NYLSCQFFQNCYETY	96
  	PD032	GWCLFSDMWLGLCSA	97
  	PD033	EFCARDWLPYQCSSF	98
  	PD034	TSYCSIEHYPCNTHH	99
  	PD035	PYICSSFPLDCQAGQ	100
  	PD036	VGCEWYMSSSGMCSR	101
  	PD037	EVCGGCSMQSVSCWP	102
  	PD038	FTECQLSPKAICMSN	103
  	PD039	KYCLFSEYVEGTCLN	104
  	PD040	SGCPMYAWGWDECWR	105
  	PD041	VDCPWYASSSAICSR	106
  	PD042	DMLLCQIRGSCAAWG	107
  	PD043	ECHPYQASASLWCGY	108

  	PD044	MMMGCMWSAWCPPSR	109
  	PD045	NAYFRCSLMCNMIMF	110
  	PD046	ACCKESVHSVHDCKR	111
  	PD047	ACIGINSYMSNYCYL	112
  	PD048	ANCSFLELTNKFCTI	113
  	PD049	AYCSYLMFASNPCII	114
  	PD050	CFTSKCPCLCYSLLA	115
  	PD051	CLCRDINCWLGCSKT	116
  	PD052	CWCDIYCSPYQCSSF	117
  	PD053	DCIYYYQQSANLCSY	118
  	PD054	DCTGVNYYIDKHCTN	119
  	PD055	DECHGYLRSSGLCGG	120
  	PD056	DICSAYAASSGFCYY	121
  	PD057	DIICVLTPTAWCGRT	122
  	PD058	DNCCMYCSWWIACRD	123
  	PD059	DSCQWYMLSADLCGT	124
  	PD060	DSVCFSSSSFLCHKS	125
  	PD061	DTMCAIWWTVCSGGR	126
  	PD062	ECTYQTSSFHEACMS	127
  	PD063	EGCNLYERSSYGCNN	128
  	PD064	EGCTAFAMSAGICGG	129
  	PD065	EQSCSLTPIAFCWSE	130
  	PD066	EWCNAYISSSKLCST	131
  	PD067	FEVCYMFASACRNGM	132
  	PD068	FSCSWYAESSSLCDI	133
  	PD069	FVCQMFEASSGLCGG	134
  	PD070	FYCPCCMFASSCGSR	135
  	PD071	FYCSYLPGASHQCSH	136
  	PD072	FYCSYLYMCEVCCYE	137
  	PD073	GFCTQHTVLTWCPTS	138
  	PD074	GSCPSYAVSAGLCYA	139
  	PD075	GSQCFLTPTAFCTHT	140
  	PD076	GTCHPYMQSSKICNN	141
  	PD077	GVECFVFTGGCGGYG	142
  	PD078	HELCNGHWVPCCWAY	143
  	PD079	ICDSYYAVSSGLCLL	144
  	PD080	IGCAWYVSSAGWCSP	145
  	PD081	INLCWMFASECGEHH	146
  	PD082	KCWLAEMTNLEHCNM	147
  	PD083	KHCSDFAYSSRLCDR	148
  	PD084	KVCSSYASSSGLCGW	149
  	PD085	LDSCYMFASYCVQAV	150
  	PD086	LLACHPIFVTVCQTR	151
  	PD087	LLSCPYNPEHVCHTS	152
  	PD088	LMCSLYALSSNLCGR	153
  	PD089	LMWCVLFLWSWCCRI	154
  	PD090	LPICHLTPTAVCTHI	155
  	PD091	LSNMCLAFGSCLYAW	156
  	PD092	LSRCHPIWYTICQNP	157
  	PD093	LTQCMSVHKECGGYE	158
  	PD094	LVNCRIWSWVCEEAT	159
  	PD095	LYCSWYQMSSAVCKE	160
  	PD096	MECGWYALSARFCEV	161
  	PD097	MTCSPYAMSAHFCNE	162
  	PD098	MVCSLYAYSASLCGA	163
  	PD099	NALCWSTFSWWCDMD	164
  	PD-100	NFTCMLTPKAYCVQT	165
  	PD-101	NGACIFTLSWCTNKT	166
  	PD-102	NGCELYAAASGLCRT	167
  	PD-103	NIECSVFGRCCCDNY	168
  	PD-104	PACRPMFWNRSCDNI	169
  	PD-105	PCRVSNMFFPYNCLD	170
  	PD-106	PIMCMLLPESYCWIW	171
  	PD-107	PQSCYMFASLCMPNG	172
  	PD-108	PRCPQGLPLYQCSSF	173
  	PD-109	PSVECLVFKRCYALP	174
  	PD-110	PVCQRSATIYNCNWF	175
  	PD-111	QCAAYYISSFGGCSN	176
  	PD-112	QFGCFMLARDFCGTY	177
  	PD-113	QMMCPYNPEHKCHQK	178
  	PD-114	QRECWMFASSCNSKN	179
  	PD-115	QSNMCTTYICSSFNY	180
  	PD-116	QSRCHSLAPYLCSSF	181
  	PD-117	RAYCSLLFADSCNNN	182
  	PD-118	RCIGINQYIDSNCYN	183
  	PD-119	RLSCFMFASQCALEF	184
  	PD-120	RQCIILMNHRQCFFK	185
  	PD-121	RSCTPYMMSSSLCNT	186

  	PD-122	RYCHYWKMPYECSSF	187
  	PD-123	SCVSLSWFDMLKCYE	188
  	PD-124	SDNCEIWWTVCSAAM	189
  	PD-125	SFCWSYLVSSGLCGV	190
  	PD-126	SMCMNNYGTTIMCGN	191
  	PD-127	SMVGCGWSTFCPSRG	192
  	PD-128	SSLHCANGHTCPFCL	193
  	PD-129	SVCSYYEESSGICSP	194
  	PD-130	SWCGWYAASSGVCAL	195
  	PD-131	TCISQTIDSYLNCVN	196
  	PD-132	TFCNLYTKSSNICMS	197
  	PD-133	TYCVFHEYLDNTCNN	198
  	PD-134	VATGCPNLMLCGSWP	199
  	PD-135	VEYCSLLLGNRCDYW	200
  	PD-136	VGCNMYLMSAGLCVD	201
  	PD-137	VLYCSWDSGTCVGSH	202
  	PD-138	VMFSCYYLETCAPGV	203
  	PD-139	VRIGLCPESCLVSGF	204
  	PD-140	VTCTYYATSSSLCNT	205
  	PD-141	VTGCILLPKAWCWGD	206
  	PD-142	VWCSIYEYSSNLCSR	207
  	PD-143	WMLECQYNNTCNNMT	208
  	PD-144	WPCSPLEYYNNICNV	209
  	PD-145	WTYDCHLNQTCPTYY	210
  	PD-146	YCSINMYLIGGNCMY	211
  	PD-147	YFCSLYANSAGFCGG	212
  	PD-148	YVSCYMFSSSCPSTW	213

Example 8: Activatable Anti-PD-1 A1.4 and A1.5 Antibodies
• This example describes examples of activatable anti-PD-1 A1.4 and A1.5 antibodies of the disclosure.
• Activatable anti-PD-1 A1.4 antibodies comprising an anti-PD-1 M13 masking moiety, a cleavable moiety, and an anti-PD-1 A1.4 antibody of the disclosure and activatable anti-PD-1 A1.5 antibodies comprising an anti-PD-1 M13 or an anti-PD-1 A1.5 masking moiety, a cleavable moiety selected from the group consisting of a cleavable moiety, and an anti-PD-1 A1.5 antibody were produced according to methods similar to those described in PCT Publication Nos. WO 2009/025846 and WO 2010/081173, the contents of which are hereby incorporated by reference in their entirety. In some embodiments, the cleavable moiety was selected from the group consisting of a cleavable moiety referred to herein as “2001” and comprising the sequence ISSGLLSGRSDNH (SEQ ID NO: 214) and a cleavable moiety referred to herein as “3001” and comprising the sequence AVGLLAPPGGLSGRSDNH (SEQ ID NO: 318). The amino acid and nucleic acid sequences of several activatable anti-PD-1 antibody variable domains of the disclosure are provided below. Antibodies were produced as hIgG4 containing a single amino acid substitution, S228P (Angal, et al. 1993. Mol Immunol 30:105-8.) HC and hK LC format.
• In some embodiments, the activatable antibody also includes a spacer sequence. In some embodiments, the spacer is joined directly to the MM of the activatable antibody. In some embodiments, the spacer is joined directly to the MM of the activatable antibody in the structural arrangement from N-terminus to C-terminus of spacer-MM-CM-AB. In some embodiments, the spacer joined directly to the N-terminus of MM of the activatable antibody is selected from the group consisting of QGQSGQG (SEQ ID NO: 362), QGQSGQ (SEQ ID NO: 913), QGQSG (SEQ ID NO: 914), QGQS (SEQ ID NO: 915), QGQ (SEQ ID NO: 916), QG (SEQ ID NO: 917), and Q. In some embodiments, the spacer includes at least the amino acid sequence QGQSGQG (SEQ ID NO: 362). In some embodiments, the spacer includes at least the amino acid sequence QGQSGQ (SEQ ID NO: 913). In some embodiments, the spacer includes at least the amino acid sequence QGQSG (SEQ ID NO: 914). In some embodiments, the spacer includes at least the amino acid sequence QGQS (SEQ ID NO: 915), In some embodiments, the spacer includes at least the amino acid sequence QGQ (SEQ ID NO: 916). In some embodiments, the spacer includes at least the amino acid sequence QG (SEQ ID NO: 917). In some embodiments, the spacer includes at least the amino acid residue Q. In some embodiments, the activatable antibody does not include a spacer sequence.
• While the sequences shown below include the spacer sequence of SEQ ID NO: 362, those of ordinary skill in the art appreciate that the activatable anti-PD-1 antibodies of the disclosure can include any suitable spacer sequence, such as, for example, a spacer sequence selected from the group consisting of QGQSGQG (SEQ ID NO: 362), QGQSGQ (SEQ ID NO: 913), QGQSG (SEQ ID NO: 914), QGQS (SEQ ID NO: 915), QGQ (SEQ ID NO: 916), QG (SEQ ID NO: 917), and Q. Additional examples of spacers include GQSGQG (SEQ ID NO: 2042), QSGQG (SEQ ID NO: 2043), SGQG (SEQ ID NO: 2044), GQG(SEQ ID NO: 2045), QG(SEQ ID NO: 2046), and G. While the sequences shown below include the spacer sequence of SEQ ID NO: 362, those of ordinary skill in the art will also appreciate that activatable anti-PD-1 antibodies of the disclosure in some embodiments do not include a spacer sequence.
Activatable Anti-PD-1 Variable Domains:

• [Spacer (SEQ ID NO: 362)]

  [PD-1 1.4 PD001 2001 (SEQ ID NO: 919)]

  (SEQ ID NO: 215)

  [QGQSGQG][AMSGCSWSAFCPYLAGGGSSGGSISSGLLSGRSDNHG

  GGSDIQLTQSPSSLSASVGDRVTITCRASESVDSYGISFMNWFQQ

  KPGKAPKLLIYAASNQGSGVPSRFSGSGSGTDFTLTISSMQPEDFATYY

  CQQSKDVPWTFGQGTKLEIK]

  PD-1 1.4 PD001 2001 Amino Acid Sequence:

  (SEQ ID NO: 1041)

  AMSGCSWSAFCPYLAGGGSSGGSISSGLLSGRSDNHGGGSDIQLTQSPSS

  LSASVGDRVTITCRASESVDSYGISFMNWFQQKPGKAPKLLIYAASNQGS

  GVPSRFSGSGSGTDFTLTISSMQPEDFATYYCQQSKDVPWTFGQGTKLEI

  K

  [Spacer (SEQ ID NO: 918)]

  [PD-1 1.4 PD001 2001 (SEQ ID NO: 920)]

  (SEQ ID NO: 216)

  [CAAGGCCAGTCTGGCCAAGGT][GCGATGAGTGGGTGCTCGTGGT

  CTGCTTTTTGCCCGTATTTGGCGGGAGGTGGCTCGAGCGGCGGCTC

  TATCTCTTCCGGACTGCTGTCCGGCAGATCCGACAATCACGGCGGAGGA

  TCCGACATCCAGCTGACCCAGAGCCCTAGCAGCCTGTCTGCCAGCGTGG

  GCGACAGAGTGACCATCACCTGTAGAGCCAGCGAGAGCGTGGACAGTTA

  CGGCATCAGCTTCATGAACTGGTTCCAGCAGAAGCCCGGCAAGGCCCCC

  AAGCTGCTGATCTACGCCGCCAGCAATCAGGGCAGCGGCGTGCCAAGCA

  GATTTTCCGGCTCTGGCAGCGGCACCGACTTCACCCTGACCATCAGCAG

  CATGCAGCCCGAGGACTTCGCCACCTACTACTGCCAGCAGAGCAAGGAC

  GTGCCCTGGACCTTTGGCCAGGGTACCAAGCTGGAAATCAAG]

  [Spacer (SEQ ID NO: 362)]

  [PD-1 1.4 PD002 2001 (SEQ ID NO: 921)]

  (SEQ ID NO: 217)

  [QGQSGQG][DVNCAIWYSVCTTVPGGGSSGGSISSGLLSGRSDNHG

  GGSDIQLTQSPSSLSASVGDRVTITCRASESVDSYGISFMNWFQQ

  KPGKAPKLLIYAASNQGSGVPSRFSGSGSGTDFTLTISSMQPEDFATYY

  CQQSKDVPWTFGQGTKLEIK]

  PD-1 1.4 PD002 2001 Amino Acid Sequence:

  (SEQ ID NO: 1042)

  DVNCAIWYSVCTTVPGGGSSGGSISSGLLSGRSDNHGGGSDIQLTQSPSS

  LSASVGDRVTITCRASESVDSYGISFMNWFQQKPGKAPKLLIYAASNQGS

  GVPSRFSGSGSGTDFTLTISSMQPEDFATYYCQQSKDVPWTFGQGTKLEI

  K

  [Spacer (SEQ ID NO: 918)]

  [PD-1 1.4 PD002 2001 (SEQ ID NO: 922)]

  (SEQ ID NO: 218)

  [CAAGGCCAGTCTGGCCAAGGT][GATGTTAATTGCGCTATTTGGTA

  TTCGGTGTGCACTACTGTTCCTGGAGGTGGCTCGAGCGGCGGCTC

  TATCTCTTCCGGACTGCTGTCCGGCAGATCCGACAATCACGGCGGAGGA

  TCCGACATCCAGCTGACCCAGAGCCCTAGCAGCCTGTCTGCCAGCGTGG

  GCGACAGAGTGACCATCACCTGTAGAGCCAGCGAGAGCGTGGACAGTTA

  CGGCATCAGCTTCATGAACTGGTTCCAGCAGAAGCCCGGCAAGGCCCCC

  AAGCTGCTGATCTACGCCGCCAGCAATCAGGGCAGCGGCGTGCCAAGCA

  GATTTTCCGGCTCTGGCAGCGGCACCGACTTCACCCTGACCATCAGCAG

  CATGCAGCCCGAGGACTTCGCCACCTACTACTGCCAGCAGAGCAAGGAC

  GTGCCCTGGACCTTTGGCCAGGGTACCAAGCTGGAAATCAAG]

  [Spacer (SEQ ID NO: 362)]

  [PD-1 1.4 PD003 2001 (SEQ ID NO: 923)]

  (SEQ ID NO: 219)

  [QGQSGQG][LVCPLYALSSGVCMGGGGSSGGSISSGLLSGRSDNHG

  GGSDIQLTQSPSSLSASVGDRVTITCRASESVDSYGISFMNWFQQ

  KPGKAPKLLIYAASNQGSGVPSRFSGSGSGTDFTLTISSMQPEDFATYY

  CQQSKDVPWTFGQGTKLEIK]

  PD-1 1.4 PD003 2001 Amino Acid Sequence:

  (SEQ ID NO: 1043)

  LVCPLYALSSGVCMGGGGSSGGSISSGLLSGRSDNHGGGSDIQLTQSPSS

  LSASVGDRVTITCRASESVDSYGISFMNWFQQKPGKAPKLLIYAASNQGS

  GVPSRFSGSGSGTDFTLTISSMQPEDFATYYCQQSKDVPWTFGQGTKLEI

  K

  [Spacer (SEQ ID NO: 918)]

  [PD-1 1.4 PD003 2001 (SEQ ID NO: 924)]

  (SEQ ID NO: 220)

  [PD-1 1.4 PD003 2001 (SEQ ID NO: 924)]

  [CAAGGCCAGTCTGGCCAAGGT][TTGGTTTGCCCTTTGTATGCATT

  GAGTTCTGGGGTGTGCATGGGGGGAGGTGGCTCGAGCGGCGGCTC

  TATCTCTTCCGGACTGCTGTCCGGCAGATCCGACAATCACGGCGGAGGA

  TCCGACATCCAGCTGACCCAGAGCCCTAGCAGCCTGTCTGCCAGCGTGG

  GCGACAGAGTGACCATCACCTGTAGAGCCAGCGAGAGCGTGGACAGTTA

  CGGCATCAGCTTCATGAACTGGTTCCAGCAGAAGCCCGGCAAGGCCCCC

  AAGCTGCTGATCTACGCCGCCAGCAATCAGGGCAGCGGCGTGCCAAGCA

  GATTTTCCGGCTCTGGCAGCGGCACCGACTTCACCCTGACCATCAGCAG

  CATGCAGCCCGAGGACTTCGCCACCTACTACTGCCAGCAGAGCAAGGAC

  GTGCCCTGGACCT

  TTGGCCAGGGTACCAAGCTGGAAATCAAG]

  [Spacer (SEQ ID NO: 362)]

  [PD-1 1.4 PD008 2001 (SEQ ID NO: 925)]

  (SEQ ID NO: 221)

  [QGQSGQG][ETCNQYERSSGLCFAGGGSSGGSISSGLLSGRSDNHG

  GGSDIQLTQSPSSLSASVGDRVTITCRASESVDSYGISFMNWFQQ

  KPGKAPKLLIYAASNQGSGVPSRFSGSGSGTDFTLTISSMQPEDFATYY

  CQQSKDVPWTFGQGTKLEIK]

  PD-1 1.4 PD008 2001 Amino Acid Sequence:

  (SEQ ID NO: 1044)

  ETCNQYERSSGLCFAGGGSSGGSISSGLLSGRSDNHGGGSDIQLTQSPSS

  LSASVGDRVTITCRASESVDSYGISFMNWFQQKPGKAPKLLIYAASNQGS

  GVPSRFSGSGSGTDFTLTISSMQPEDFATYYCQQSKDVPWTFGQGTKLEI

  K

  [Spacer (SEQ ID NO: 918)]

  [PD-1 1.4 PD008 2001 (SEQ ID NO: 926)]

  (SEQ ID NO: 222)

  [CAAGGCCAGTCTGGCCAAGGT][GAGACTTGCAATCAGTATGAGAG

  GTCGAGTGGTTTGTGCTTTGCGGGAGGTGGCTCGAGCGGCGGCTC

  TATCTCTTCCGGACTGCTGTCCGGCAGATCCGACAATCACGGCGGAGGA

  TCCGACATCCAGCTGACCCAGAGCCCTAGCAGCCTGTCTGCCAGCGTGG

  GCGACAGAGTGACCATCACCTGTAGAGCCAGCGAGAGCGTGGACAGTTA

  CGGCATCAGCTTCATGAACTGGTTCCAGCAGAAGCCCGGCAAGGCCCCC

  AAGCTGCTGATCTACGCCGCCAGCAATCAGGGCAGCGGCGTGCCAAGCA

  GATTTTCCGGCTCTGGCAGCGGCACCGACTTCACCCTGACCATCAGCAG

  CATGCAGCCCGAGGACTTCGCCACCTACTACTGCCAGCAGAGCAAGGAC

  GTGCCCTGGACCTTTGGCCAGGGTACCAAGCTGGAAATCAAG]

  [Spacer (SEQ ID NO: 362)]

  [PD-1 1.4 PD009 2001 (SEQ ID NO: 927)]

  (SEQ ID NO: 223)

  [QGQSGQG][APRTCYTYQCSSFYTGGGSSGGSISSGLLSGRSDNHG

  GGSDIQLTQSPSSLSASVGDRVTITCRASESVDSYGISFMNWFQQ

  KPGKAPKLLIYAASNQGSGVPSRFSGSGSGTDFTLTISSMQPEDFATYY

  CQQSKDVPWTFGQGTKLEIK]

  PD-1 1.4 PD009 2001 Amino Acid Sequence:

  (SEQ ID NO: 1045)

  APRTCYTYQCSSFYTGGGSSGGSISSGLLSGRSDNHGGGSDIQLTQSPSS

  LSASVGDRVTITCRASESVDSYGISFMNWFQQKPGKAPKLLIYAASNQGS

  GVPSRFSGSGSGTDFTLTISSMQPEDFATYYCQQSKDVPWTFGQGTKLEI

  K

  [Spacer (SEQ ID NO: 918)]

  [PD-1 1.4 PD009 2001 (SEQ ID NO: 928)]

  (SEQ ID NO: 224)

  [CAAGGCCAGTCTGGCCAAGGT][GCGCCGCGGACGTGCTATACGTA

  TCAGTGCTCTAGTTTTTATACTGGAGGTGGCTCGAGCGGCGGCTC

  TATCTCTTCCGGACTGCTGTCCGGCAGATCCGACAATCACGGCGGAGGA

  TCCGACATCCAGCTGACCCAGAGCCCTAGCAGCCTGTCTGCCAGCGTGG

  GCGACAGAGTGACCATCACCTGTAGAGCCAGCGAGAGCGTGGACAGTTA

  CGGCATCAGCTTCATGAACTGGTTCCAGCAGAAGCCCGGCAAGGCCCCC

  AAGCTGCTGATCTACGCCGCCAGCAATCAGGGCAGCGGCGTGCCAAGCA

  GATTTTCCGGCTCTGGCAGCGGCACCGACTTCACCCTGACCATCAGCAG

  CATGCAGCCCGAGGACTTCGCCACCTACTACTGCCAGCAGAGCAAGGAC

  GTGCCCTGGACCTTTGGCCAGGGTACCAAGCTGGAAATCAAG]

  [Spacer (SEQ ID NO: 362)]

  [PD-1 1.4 PD010 2001 (SEQ ID NO: 929)]

  (SEQ ID NO: 225)

  [QGQSGQG][GLCSWYLSSSGLCVDGGGSSGGSISSGLLSGRSDNHG

  GGSDIQLTQSPSSLSASVGDRVTITCRASESVDSYGISFMNWFQQ

  KPGKAPKLLIYAASNQGSGVPSRFSGSGSGTDFTLTISSMQPEDFATYY

  CQQSKDVPWTFGQGTKLEIK]

  PD-1 1.4 PD010 2001 Amino Acid Sequence:

  (SEQ ID NO: 1046)

  GLCSWYLSSSGLCVDGGGSSGGSISSGLLSGRSDNHGGGSDIQLTQSPSS

  LSASVGDRVTITCRASESVDSYGISFMNWFQQKPGKAPKLLIYAASNQGS

  GVPSRFSGSGSGTDFTLTISSMQPEDFATYYCQQSKDVPWTFGQGTKLEI

  K

  [Spacer (SEQ ID NO: 918)]

  [PD-1 1.4 PD010 2001 (SEQ ID NO: 930)]

  (SEQ ID NO: 226)

  [CAAGGCCAGTCTGGCCAAGGT][GGTCTTTGCAGTTGGTATCT

  TAGTAGTTCGGGTTTGTGCGTGGATGGAGGTGGCTCGAGCGGCGGCTCTA

  TCTCTTCCGGACTGCTGTCCGGCAGATCCGACAATCACGGCGGAGGATCC

  GACATCCAGCTGACCCAGAGCCCTAGCAGCCTGTCTGCCAGCGTGGGCGA

  CAGAGTGACCATCACCTGTAGAGCCAGCGAGAGCGTGGACAGTTACGGCA

  TCAGCTTCATGAACTGGTTCCAGCAGAAGCCCGGCAAGGCCCCCAAGCTG

  CTGATCTACGCCGCCAGCAATCAGGGCAGCGGCGTGCCAAGCAGATTTTC

  CGGCTCTGGCAGCGGCACCGACTTCACCCTGACCATCAGCAGCATGCAGC

  CCGAGGACTTCGCCACCTACTACTGCCAGCAGAGCAAGGACGTGCCCTGG

  ACCTTTGGCCAGGGTACCAAGCTGGAAATCAAG]

  [Spacer (SEQ ID NO: 362)]

  [PD-1 1.5 PD01 2001 (SEQ ID NO: 931)]

  (SEQ ID NO: 227)

  [QGQSGQG][AMSGCSWSAFCPYLAGGGSSGGSISSGLLSGRSD

  NHGGGSDIQLTQSPSSLSASVGDRVTITCRASESVDAYGISFMNWFQQKP

  GKAPKLLIYAASNQGSGVPSRFSGSGSGTDFTLTISSMQPEDFATYYCQQ

  SKDVPWTFGQGTKLEIK]

  PD-1 1.5 PD01 2001 Amino Acid Sequence:

  (SEQ ID NO: 1047)

  AMSGCSWSAFCPYLAGGGSSGGSISSGLLSGRSDNHGGGSDIQLTQSPSS

  LSASVGDRVTITCRASESVDAYGISFMNWFQQKPGKAPKLLIYAASNQGS

  GVPSRFSGSGSGTDFTLTISSMQPEDFATYYCQQSKDVPWTFGQGTKLEI

  K

  [Spacer (SEQ ID NO: 918)]

  [PD-1 1.5 PD001 2001 (SEQ ID NO: 932)]

  (SEQ ID NO: 228)

  [CAAGGCCAGTCTGGCCAAGGT][GCGATGAGTGGGTGCTCGTG

  GTCTGCTTTTTGCCCGTATTTGGCGGGAGGTGGCTCGAGCGGCGGCTCTA

  TCTCTTCCGGACTGCTGTCCGGCAGATCCGACAATCACGGCGGAGGATCC

  GATATCCAGCTGACCCAGAGCCCTAGCAGCCTGTCTGCCAGCGTGGGCGA

  CAGAGTGACCATCACCTGTAGAGCCAGCGAGAGCGTGGACGCTTACGGCA

  TCAGCTTCATGAACTGGTTCCAGCAGAAGCCCGGCAAGGCCCCCAAGCTG

  CTGATCTACGCCGCCAGCAATCAGGGCAGCGGCGTGCCAAGCAGATTTTC

  CGGCTCTGGCAGCGGCACCGACTTCACCCTGACCATCAGCAGCATGCAGC

  CCGAGGACTTCGCCACCTACTACTGCCAGCAGAGCAAGGACGTGCCCTGG

  ACCTTTGGCCAGGGTACCAAGCTGGAAATCAAG]

  [Spacer (SEQ ID NO: 362)]

  [PD-1 1.5 PD002 2001 (SEQ ID NO: 933)]

  (SEQ ID NO: 229)

  [QGQSGQG][DVNCAIWYSVCTTVPGGGSSGGSISSGLLSGRSD

  NHGGGSDIQLTQSPSSLSASVGDRVTITCRASESVDAYGISFMNWFQQKP

  GKAPKLLIYAASNQGSGVPSRFSGSGSGTDFTLTISSMQPEDFATYYCQQ

  SKDVPWTFGQGTKLEIK]

  PD-1 1.5 PD002 2001 Amino Acid Sequence:

  (SEQ ID NO: 1048)

  DVNCAIWYSVCTTVPGGGSSGGSISSGLLSGRSDNHGGGSDIQLTQSPSS

  LSASVGDRVTITCRASESVDAYGISFMNWFQQKPGKAPKLLIYAASNQGS

  GVPSRFSGSGSGTDFTLTISSMQPEDFATYYCQQSKDVPWTFGQGTKLEI

  K

  [Spacer (SEQ ID NO: 918)]

  [PD-1 1.5 PD002 2001 (SEQ ID NO: 934)]

  (SEQ ID NO: 230)

  [CAAGGCCAGTCTGGCCAAGGT][GATGTTAATTGCGCTATTTG

  GTATTCGGTGTGCACTACTGTTCCTGGAGGTGGCTCGAGCGGCGGCTCTA

  TCTCTTCCGGACTGCTGTCCGGCAGATCCGACAATCACGGCGGAGGATCC

  GATATCCAGCTGACCCAGAGCCCTAGCAGCCTGTCTGCCAGCGTGGGCGA

  CAGAGTGACCATCACCTGTAGAGCCAGCGAGAGCGTGGACGCTTACGGCA

  TCAGCTTCATGAACTGGTTCCAGCAGAAGCCCGGCAAGGCCCCCAAGCTG

  CTGATCTACGCCGCCAGCAATCAGGGCAGCGGCGTGCCAAGCAGATTTTC

  CGGCTCTGGCAGCGGCACCGACTTCACCCTGACCATCAGCAGCATGCAGC

  CCGAGGACTTCGCCACCTACTACTGCCAGCAGAGCAAGGACGTGCCCTGG

  ACCTTTGGCCAGGGTACCAAGCTGGAAATCAAG]

  [Spacer (SEQ ID NO: 362)]

  [PD-1 1.5 PD003 2001 (SEQ ID NO: 935)]

  (SEQ ID NO: 231)

  [QGQSGQG][LVCPLYALSSGVCMGGGGSSGGSISSGLLSGRSD

  NHGGGSDIQLTQSPSSLSASVGDRVTITCRASESVDAYGISFMNWFQQKP

  GKAPKLLIYAASNQGSGVPSRFSGSGSGTDFTLTISSMQPEDFATYYCQQ

  SKDVPWTFGQGTKLEIK]

  PD-1 1.5 PD003 2001 Amino Acid Sequence:

  (SEQ ID NO: 1049)

  LVCPLYALSSGVCMGGGGSSGGSISSGLLSGRSDNHGGGSDIQLTQSPSS

  LSASVGDRVTITCRASESVDAYGISFMNWFQQKPGKAPKLLIYAASNQGS

  GVPSRFSGSGSGTDFTLTISSMQPEDFATYYCQQSKDVPWTFGQGTKLEI

  K

  [Spacer (SEQ ID NO: 918)]

  [PD-1 1.5 PD003 2001 (SEQ ID NO: 936)]

  (SEQ ID NO: 232)

  [CAAGGCCAGTCTGGCCAAGGT][TTGGTTTGCCCTTTGTATGC

  ATTGAGTTCTGGGGTGTGCATGGGGGGAGGTGGCTCGAGCGGCGGCTCTA

  TCTCTTCCGGACTGCTGTCCGGCAGATCCGACAATCACGGCGGAGGATCC

  GATATCCAGCTGACCCAGAGCCCTAGCAGCCTGTCTGCCAGCGTGGGCGA

  CAGAGTGACCATCACCTGTAGAGCCAGCGAGAGCGTGGACGCTTACGGCA

  TCAGCTTCATGAACTGGTTCCAGCAGAAGCCCGGCAAGGCCCCCAAGCTG

  CTGATCTACGCCGCCAGCAATCAGGGCAGCGGCGTGCCAAGCAGATTTTC

  CGGCTCTGGCAGCGGCACCGACTTCACCCTGACCATCAGCAGCATGCAGC

  CCGAGGACTTCGCCACCTACTACTGCCAGCAGAGCAAGGACGTGCCCTGG

  ACCTTTGGCCAGGGTACCAAGCTGGAAATCAAG]

  [Spacer (SEQ ID NO: 362)]

  [PD-1 1.5 PD004 2001 (SEQ ID NO: 937)]

  (SEQ ID NO: 233)

  [QGQSGQG][SVNCRIWSAVCAGYEGGGSSGGSISSGLLSGRSD

  NHGGGSDIQLTQSPSSLSASVGDRVTITCRASESVDAYGISFMNWFQQKP

  GKAPKLLIYAASNQGSGVPSRFSGSGSGTDFTLTISSMQPEDFATYYCQQ

  SKDVPWTFGQGTKLEIK]

  PD-1 1.5 PD004 2001 Amino Acid Sequence:

  (SEQ ID NO: 1050)

  SVNCRIWSAVCAGYEGGGSSGGSISSGLLSGRSDNHGGGSDIQLTQSPSS

  LSASVGDRVTITCRASESVDAYGISFMNWFQQKPGKAPKLLIYAASNQGS

  GVPSRFSGSGSGTDFTLTISSMQPEDFATYYCQQSKDVPWTFGQGTKLEI

  K

  [Spacer (SEQ ID NO: 918)]

  [PD-1 1.5 PD004 2001 (SEQ ID NO: 938)]

  (SEQ ID NO: 234)

  [CAAGGCCAGTCTGGCCAAGGT][TCTGTGAATTGCCGGATTTG

  GTCGGCTGTTTGCGCGGGGTATGAGGGAGGTGGCTCGAGCGGCGGCTCTA

  TCTCTTCCGGACTGCTGTCCGGCAGATCCGACAATCACGGCGGAGGATCC

  GATATCCAGCTGACCCAGAGCCCTAGCAGCCTGTCTGCCAGCGTGGGCGA

  CAGAGTGACCATCACCTGTAGAGCCAGCGAGAGCGTGGACGCTTACGGCA

  TCAGCTTCATGAACTGGTTCCAGCAGAAGCCCGGCAAGGCCCCCAAGCTG

  CTGATCTACGCCGCCAGCAATCAGGGCAGCGGCGTGCCAAGCAGATTTTC

  CGGCTCTGGCAGCGGCACCGACTTCACCCTGACCATCAGCAGCATGCAGC

  CCGAGGACTTCGCCACCTACTACTGCCAGCAGAGCAAGGACGTGCCCTGG

  ACCTTTGGCCAGGGTACCAAGCTGGAAATCAAG]

  [Spacer (SEQ ID NO: 362)]

  [PD-1 1.5 PD005 2001 (SEQ ID NO: 939)]

  (SEQ ID NO: 235)

  [QGQSGQG][MLVCSLQPTAMCERVGGGSSGGSISSGLLSGRSD

  NHGGGSDIQLTQSPSSLSASVGDRVTITCRASESVDAYGISFMNWFQQKP

  GKAPKLLIYAASNQGSGVPSRFSGSGSGTDFTLTISSMQPEDFATYYCQQ

  SKDVPWTFGQGTKLEIK]

  PD-1 1.5 PD005 2001 Amino Acid Sequence:

  (SEQ ID NO: 1051)

  MLVCSLQPTAMCERVGGGSSGGSISSGLLSGRSDNHGGGSDIQLTQSPSS

  LSASVGDRVTITCRASESVDAYGISFMNWFQQKPGKAPKLLIYAASNQGS

  GVPSRFSGSGSGTDFTLTISSMQPEDFATYYCQQSKDVPWTFGQGTKLEI

  K

  [Spacer (SEQ ID NO: 918)]

  [PD-1 1.5 PD005 2001 (SEQ ID NO: 940)]

  (SEQ ID NO: 236)

  [CAAGGCCAGTCTGGCCAAGGT][ATGCTTGTGTGCTCGTTGCAGCCTAC

  TGCGATGTGCGAGCGGGTGGGAGGTGGCTCGAGCGGCGGCTCTATCTCTT

  CCGGACTGCTGTCCGGCAGATCCGACAATCACGGCGGAGGATCCGATATC

  CAGCTGACCCAGAGCCCTAGCAGCCTGTCTGCCAGCGTGGGCGACAGAGT

  GACCATCACCTGTAGAGCCAGCGAGAGCGTGGACGCTTACGGCATCAGCT

  TCATGAACTGGTTCCAGCAGAAGCCCGGCAAGGCCCCCAAGCTGCTGATC

  TACGCCGCCAGCAATCAGGGCAGCGGCGTGCCAAGCAGATTTTCCGGCTC

  TGGCAGCGGCACCGACTTCACCCTGACCATCAGCAGCATGCAGCCCGAGG

  ACTTCGCCACCTACTACTGCCAGCAGAGCAAGGACGTGCCCTGGACCTTT

  GGCCAGGGTACCAAGCTGGAAATCAAG]

  [Spacer (SEQ ID NO: 362)]

  [PD-1 1.5 PD006 2001 (SEQ ID NO: 941)]

  (SEQ ID NO: 237)

  [QGQSGQG][APRCYMFASYCKSQYGGGSSGGSISSGLLSGRSDNHGGGS

  DIQLTQSPSSLSASVGDRVTITCRASESVDAYGISFMNWFQQKPGKAPKL

  LIYAASNQGSGVPSRFSGSGSGTDFTLTISSMQPEDFATYYCQQSKDVPW

  TFGQGTKLEIK]

  PD-1 1.5 PD006 2001 Amino Acid Sequence:

  (SEQ ID NO: 941)

  APRCYMFASYCKSQYGGGSSGGSISSGLLSGRSDNHGGGSDIQLTQSPSS

  LSASVGDRVTITCRASESVDAYGISFMNWFQQKPGKAPKLLIYAASNQGS

  GVPSRFSGSGSGTDFTLTISSMQPEDFATYYCQQSKDVPWTFGQGTKLEI

  K

  [Spacer (SEQ ID NO: 918)]

  [PD-1 1.5 PD006 2001 (SEQ ID NO: 942)]

  (SEQ ID NO: 238)

  [CAAGGCCAGTCTGGCCAAGGT][GCGCCTAGGTGCTATATGTTTGCGTC

  GTATTGCAAGAGTCAGTATGGAGGTGGCTCGAGCGGCGGCTCTATCTCTT

  CCGGACTGCTGTCCGGCAGATCCGACAATCACGGCGGAGGATCCGATATC

  CAGCTGACCCAGAGCCCTAGCAGCCTGTCTGCCAGCGTGGGCGACAGAGT

  GACCATCACCTGTAGAGCCAGCGAGAGCGTGGACGCTTACGGCATCAGCT

  TCATGAACTGGTTCCAGCAGAAGCCCGGCAAGGCCCCCAAGCTGCTGATC

  TACGCCGCCAGCAATCAGGGCAGCGGCGTGCCAAGCAGATTTTCCGGCTC

  TGGCAGCGGCACCGACTTCACCCTGACCATCAGCAGCATGCAGCCCGAGG

  ACTTCGCCACCTACTACTGCCAGCAGAGCAAGGACGTGCCCTGGACCTTT

  GGCCAGGGTACCAAGCTGGAAATCAAG]

  PD-1 1.5 PD006 2001 Nucleic Acid Sequence:

  (SEQ ID NO: 942)

  GCGCCTAGGTGCTATATGTTTGCGTCGTATTGCAAGAGTCAGTATGGAGG

  TGGCTCGAGCGGCGGCTCTATCTCTTCCGGACTGCTGTCCGGCAGATCCG

  ACAATCACGGCGGAGGATCCGATATCCAGCTGACCCAGAGCCCTAGCAGC

  CTGTCTGCCAGCGTGGGCGACAGAGTGACCATCACCTGTAGAGCCAGCGA

  GAGCGTGGACGCTTACGGCATCAGCTTCATGAACTGGTTCCAGCAGAAGC

  CCGGCAAGGCCCCCAAGCTGCTGATCTACGCCGCCAGCAATCAGGGCAGC

  GGCGTGCCAAGCAGATTTTCCGGCTCTGGCAGCGGCACCGACTTCACCCT

  GACCATCAGCAGCATGCAGCCCGAGGACTTCGCCACCTACTACTGCCAGC

  AGAGCAAGGACGTGCCCTGGACCTTTGGCCAGGGTACCAAGCTGGAAATC

  AAG

  [Spacer (SEQ ID NO: 362)]

  [PD-1 1.5 PD007 2001 (SEQ ID NO: 943)]

  (SEQ ID NO: 239)

  [QGQSGQG][VGPCELTPKPVCNTYGGGSSGGSISSGLLSGRSDNHGGGS

  DIQLTQSPSSLSASVGDRVTITCRASESVDAYGISFMNWFQQKPGKAPKL

  LIYAASNQGSGVPSRFSGSGSGTDFTLTISSMQPEDFATYYCQQSKDVPW

  TFGQGTKLEIK]

  PD-1 1.5 PD007 2001 Amino Acid Sequence:

  (SEQ ID NO: 1052)

  VGPCELTPKPVCNTYGGGSSGGSISSGLLSGRSDNHGGGSDIQLTQSPSS

  LSASVGDRVTITCRASESVDAYGISFMNWFQQKPGKAPKLLIYAASNQGS

  GVPSRFSGSGSGTDFTLTISSMQPEDFATYYCQQSKDVPWTFGQGTKLEI

  K

  [Spacer (SEQ ID NO: 918)]

  [PD-1 1.5 PD007 2001 (SEQ ID NO: 944)]

  (SEQ ID NO: 240)

  [CAAGGCCAGTCTGGCCAAGGT][GTGGGGCCTTGCGAGTTGACGCCGAA

  GCCTGTTTGCAATACGTATGGAGGTGGCTCGAGCGGCGGCTCTATCTCTT

  CCGGACTGCTGTCCGGCAGATCCGACAATCACGGCGGAGGATCCGATATC

  CAGCTGACCCAGAGCCCTAGCAGCCTGTCTGCCAGCGTGGGCGACAGAGT

  GACCATCACCTGTAGAGCCAGCGAGAGCGTGGACGCTTACGGCATCAGCT

  TCATGAACTGGTTCCAGCAGAAGCCCGGCAAGGCCCCCAAGCTGCTGATC

  TACGCCGCCAGCAATCAGGGCAGCGGCGTGCCAAGCAGATTTTCCGGCTC

  TGGCAGCGGCACCGACTTCACCCTGACCATCAGCAGCATGCAGCCCGAGG

  ACTTCGCCACCTACTACTGCCAGCAGAGCAAGGACGTGCCCTGGACCTTT

  GGCCAGGGTACCAAGCTGGAAATCAAG]

  [Spacer (SEQ ID NO: 362)]

  [PD-1 1.5 PD008 2001 (SEQ ID NO: 945)]

  (SEQ ID NO: 241)

  [QGQSGQG][ETCNQYERSSGLCFAGGGSSGGSISSGLLSGRSDNHGGGS

  DIQLTQSPSSLSASVGDRVTITCRASESVDAYGISFMNWFQQKPGKAPKL

  LIYAASNQGSGVPSRFSGSGSGTDFTLTISSMQPEDFATYYCQQSKDVPW

  TFGQGTKLEIK]

  PD-1 1.5 PD008 2001 Amino Acid Sequence:

  (SEQ ID NO: 1053)

  ETCNQYERSSGLCFAGGGSSGGSISSGLLSGRSDNHGGGSDIQLTQSPSS

  LSASVGDRVTITCRASESVDAYGISFMNWFQQKPGKAPKLLIYAASNQGS

  GVPSRFSGSGSGTDFTLTISSMQPEDFATYYCQQSKDVPWTFGQGTKLEI

  K

  [Spacer (SEQ ID NO: 918)]

  [PD-1 1.5 PD008 2001 (SEQ ID NO: 946)]

  (SEQ ID NO: 242)

  [CAAGGCCAGTCTGGCCAAGGT][GAGACTTGCAATCAGTATGAGAGGTC

  GAGTGGTTTGTGCTTTGCGGGAGGTGGCTCGAGCGGCGGCTCTATCTCTT

  CCGGACTGCTGTCCGGCAGATCCGACAATCACGGCGGAGGATCCGATATC

  CAGCTGACCCAGAGCCCTAGCAGCCTGTCTGCCAGCGTGGGCGACAGAGT

  GACCATCACCTGTAGAGCCAGCGAGAGCGTGGACGCTTACGGCATCAGCT

  TCATGAACTGGTTCCAGCAGAAGCCCGGCAAGGCCCCCAAGCTGCTGATC

  TACGCCGCCAGCAATCAGGGCAGCGGCGTGCCAAGCAGATTTTCCGGCTC

  TGGCAGCGGCACCGACTTCACCCTGACCATCAGCAGCATGCAGCCCGAGG

  ACTTCGCCACCTACTACTGCCAGCAGAGCAAGGACGTGCCCTGGACCTTT

  GGCCAGGGTACCAAGCTGGAAATCAAG]

  [Spacer (SEQ ID NO: 362)]

  [PD-1 1.5 PD009 2001 (SEQ ID NO: 947)]

  (SEQ ID NO: 243)

  [QGQSGQG][APRTCYTYQCSSFYTGGGSSGGSISSGLLSGRSDNHGGGS

  DIQLTQSPSSLSASVGDRVTITCRASESVDAYGISFMNWFQQKPGKAPKL

  LIYAASNQGSGVPSRFSGSGSGTDFTLTISSMQPEDFATYYCQQSKDVPW

  TFGQGTKLEIK]

  PD-1 1.5 PD009 2001 Amino Acid Sequence:

  (SEQ ID NO: 1054)

  APRTCYTYQCSSFYTGGGSSGGSISSGLLSGRSDNHGGGSDIQLTQSPSS

  LSASVGDRVTITCRASESVDAYGISFMNWFQQKPGKAPKLLIYAASNQGS

  GVPSRFSGSGSGTDFTLTISSMQPEDFATYYCQQSKDVPWTFGQGTKLEI

  K

  [Spacer (SEQ ID NO: 918)]

  [PD-1 1.5 PD009 2001 (SEQ ID NO: 948)]

  (SEQ ID NO: 244)

  [CAAGGCCAGTCTGGCCAAGGT][GCGCCGCGGACGTGCTATACGTATCA

  GTGCTCTAGTTTTTATACTGGAGGTGGCTCGAGCGGCGGCTCTATCTCTT

  CCGGACTGCTGTCCGGCAGATCCGACAATCACGGCGGAGGATCCGATATC

  CAGCTGACCCAGAGCCCTAGCAGCCTGTCTGCCAGCGTGGGCGACAGAGT

  GACCATCACCTGTAGAGCCAGCGAGAGCGTGGACGCTTACGGCATCAGCT

  TCATGAACTGGTTCCAGCAGAAGCCCGGCAAGGCCCCCAAGCTGCTGATC

  TACGCCGCCAGCAATCAGGGCAGCGGCGTGCCAAGCAGATTTTCCGGCTC

  TGGCAGCGGCACCGACTTCACCCTGACCATCAGCAGCATGCAGCCCGAGG

  ACTTCGCCACCTACTACTGCCAGCAGAGCAAGGACGTGCCCTGGACCTTT

  GGCCAGGGTACCAAGCTGGAAATCAAG]

  [Spacer (SEQ ID NO: 362)]

  [PD-1 1.5 PD010 2001 (SEQ ID NO: 949)]

  (SEQ ID NO: 245)

  [QGQSGQG][GLCSWYLSSSGLCVDGGGSSGGSISSGLLSGRSDNHGGGS

  DIQLTQSPSSLSASVGDRVTITCRASESVDAYGISFMNWFQQKPGKAPKL

  LIYAASNQGSGVPSRFSGSGSGTDFTLTISSMQPEDFATYYCQQSKDVPW

  TFGQGTKLEIK]

  PD-1 1.5 PD010 2001 Amino Acid Sequence:

  (SEQ ID NO: 1055)

  GLCSWYLSSSGLCVDGGGSSGGSISSGLLSGRSDNHGGGSDIQLTQSPSS

  LSASVGDRVTITCRASESVDAYGISFMNWFQQKPGKAPKLLIYAASNQGS

  GVPSRFSGSGSGTDFTLTISSMQPEDFATYYCQQSKDVPWTFGQGTKLEI

  K

  [Spacer (SEQ ID NO: 918)]

  [PD-1 1.5 PD010 2001 (SEQ ID NO: 950)]

  (SEQ ID NO: 246)

  [CAAGGCCAGTCTGGCCAAGGT][GGTCTTTGCAGTTGGTATCTTAGTAG

  TTCGGGTTTGTGCGTGGATGGAGGTGGCTCGAGCGGCGGCTCTATCTCTT

  CCGGACTGCTGTCCGGCAGATCCGACAATCACGGCGGAGGATCCGATATC

  CAGCTGACCCAGAGCCCTAGCAGCCTGTCTGCCAGCGTGGGCGACAGAGT

  GACCATCACCTGTAGAGCCAGCGAGAGCGTGGACGCTTACGGCATCAGCT

  TCATGAACTGGTTCCAGCAGAAGCCCGGCAAGGCCCCCAAGCTGCTGATC

  TACGCCGCCAGCAATCAGGGCAGCGGCGTGCCAAGCAGATTTTCCGGCTC

  TGGCAGCGGCACCGACTTCACCCTGACCATCAGCAGCATGCAGCCCGAGG

  ACTTCGCCACCTACTACTGCCAGCAGAGCAAGGACGTGCCCTGGACCTTT

  GGCCAGGGTACCAAGCTGGAAATCAAG]

  [Spacer (SEQ ID NO: 362)]

  [PD-1 1.5 PD011 2001 (SEQ ID NO: 951)]

  (SEQ ID NO: 247)

  [QGQSGQG][VPWCQLTPRVMCMWAGGGSSGGSISSGLLSGRSDNHGGGS

  DIQLTQSPSSLSASVGDRVTITCRASESVDAYGISFMNWFQQKPGKAPKL

  LIYAASNQGSGVPSRFSGSGSGTDFTLTISSMQPEDFATYYCQQSKDVPW

  TFGQGTKLEIK]

  PD-1 1.5 PD011 2001 Amino Acid Sequence:

  (SEQ ID NO: 1056)

  VPWCQLTPRVMCMWAGGGSSGGSISSGLLSGRSDNHGGGSDIQLTQSPSS

  LSASVGDRVTITCRASESVDAYGISFMNWFQQKPGKAPKLLIYAASNQGS

  GVPSRFSGSGSGTDFTLTISSMQPEDFATYYCQQSKDVPWTFGQGTKLEI

  K

  [Spacer (SEQ ID NO: 918)]

  [PD-1 1.5 PD011 2001 (SEQ ID NO: 952)]

  (SEQ ID NO: 248)

  [CAAGGCCAGTCTGGCCAAGGT][GTGCCTTGGTGCCAGTTGACGCCGCG

  GGTTATGTGCATGTGGGCGGGAGGTGGCTCGAGCGGCGGCTCTATCTCTT

  CCGGACTGCTGTCCGGCAGATCCGACAATCACGGCGGAGGATCCGATATC

  CAGCTGACCCAGAGCCCTAGCAGCCTGTCTGCCAGCGTGGGCGACAGAGT

  GACCATCACCTGTAGAGCCAGCGAGAGCGTGGACGCTTACGGCATCAGCT

  TCATGAACTGGTTCCAGCAGAAGCCCGGCAAGGCCCCCAAGCTGCTGATC

  TACGCCGCCAGCAATCAGGGCAGCGGCGTGCCAAGCAGATTTTCCGGCTC

  TGGCAGCGGCACCGACTTCACCCTGACCATCAGCAGCATGCAGCCCGAGG

  ACTTCGCCACCTACTACTGCCAGCAGAGCAAGGACGTGCCCTGGACCTTT

  GGCCAGGGTACCAAGCTGGAAATCAAG]

  [Spacer (SEQ ID NO: 362)]

  [PD-1 1.5 PD012 2001 (SEQ ID NO: 953)]

  (SEQ ID NO: 249)

  [QGQSGQG][NWLDCQFYSECSVYGGGGSSGGSISSGLLSGRSDNHGGGS

  DIQLTQSPSSLSASVGDRVTITCRASESVDAYGISFMNWFQQKPGKAPKL

  LIYAASNQGSGVPSRFSGSGSGTDFTLTISSMQPEDFATYYCQQSKDVPW

  TFGQGTKLEIK]

  PD-1 1.5 PD012 2001 Amino Acid Sequence:

  (SEQ ID NO: 953)

  NWLDCQFYSECSVYGGGGSSGGSISSGLLSGRSDNHGGGSDIQLTQSPSS

  LSASVGDRVTITCRASESVDAYGISFMNWFQQKPGKAPKLLIYAASNQGS

  GVPSRFSGSGSGTDFTLTISSMQPEDFATYYCQQSKDVPWTFGQGTKLEI

  K

  [Spacer (SEQ ID NO: 918)]

  [PD-1 1.5 PD012 2001 (SEQ ID NO: 954)]

  (SEQ ID NO: 250)

  [CAAGGCCAGTCTGGCCAAGGT][AATTGGTTGGATTGCCAGTTTTATTC

  TGAGTGCTCTGTTTATGGTGGAGGTGGCTCGAGCGGCGGCTCTATCTCTT

  CCGGACTGCTGTCCGGCAGATCCGACAATCACGGCGGAGGATCCGATATC

  CAGCTGACCCAGAGCCCTAGCAGCCTGTCTGCCAGCGTGGGCGACAGAGT

  GACCATCACCTGTAGAGCCAGCGAGAGCGTGGACGCTTACGGCATCAGCT

  TCATGAACTGGTTCCAGCAGAAGCCCGGCAAGGCCCCCAAGCTGCTGATC

  TACGCCGCCAGCAATCAGGGCAGCGGCGTGCCAAGCAGATTTTCCGGCTC

  TGGCAGCGGCACCGACTTCACCCTGACCATCAGCAGCATGCAGCCCGAGG

  ACTTCGCCACCTACTACTGCCAGCAGAGCAAGGACGTGCCCTGGACCTTT

  GGCCAGGGTACCAAGCTGGAAATCAAG]

  PD-1 1.5 PD012 2001 Nucleic Acid Sequence:

  (SEQ ID NO: 954)

  AATTGGTTGGATTGCCAGTTTTATTCTGAGTGCTCTGTTTATGGTGGAGG

  TGGCTCGAGCGGCGGCTCTATCTCTTCCGGACTGCTGTCCGGCAGATCCG

  ACAATCACGGCGGAGGATCCGATATCCAGCTGACCCAGAGCCCTAGCAGC

  CTGTCTGCCAGCGTGGGCGACAGAGTGACCATCACCTGTAGAGCCAGCGA

  GAGCGTGGACGCTTACGGCATCAGCTTCATGAACTGGTTCCAGCAGAAGC

  CCGGCAAGGCCCCCAAGCTGCTGATCTACGCCGCCAGCAATCAGGGCAGC

  GGCGTGCCAAGCAGATTTTCCGGCTCTGGCAGCGGCACCGACTTCACCCT

  GACCATCAGCAGCATGCAGCCCGAGGACTTCGCCACCTACTACTGCCAGC

  AGAGCAAGGACGTGCCCTGGACCTTTGGCCAGGGTACCAAGCTGGAAATC

  AAG

  [Spacer (SEQ ID NO: 362)]

  [PD-1 1.5 PD013 2001 (SEQ ID NO: 955)]

  (SEQ ID NO: 251)

  [QGQSGQG][SCPLYVMSSFGGCWDGGGSSGGSISSGLLSGRSDNHGGGS

  DIQLTQSPSSLSASVGDRVTITCRASESVDAYGISFMNWFQQKPGKAPKL

  LIYAASNQGSGVPSRFSGSGSGTDFTLTISSMQPEDFATYYCQQSKDVPW

  TFGQGTKLEIK]

  PD-1 1.5 PD013 2001 Amino Acid Sequence:

  (SEQ ID NO: 1057)

  SCPLYVMSSFGGCWDGGGSSGGSISSGLLSGRSDNHGGGSDIQLTQSPSS

  LSASVGDRVTITCRASESVDAYGISFMNWFQQKPGKAPKLLIYAASNQGS

  GVPSRFSGSGSGTDFTLTISSMQPEDFATYYCQQSKDVPWTFGQGTKLEI

  K

  [Spacer (SEQ ID NO: 918)]

  [PD-1 1.5 PD013 2001 (SEQ ID NO: 956)]

  (SEQ ID NO: 252)

  [CAAGGCCAGTCTGGCCAAGGT][TCGTGCCCTTTGTATGTGATGTCTAG

  TTTTGGTGGGTGCTGGGATGGAGGTGGCTCGAGCGGCGGCTCTATCTCTT

  CCGGACTGCTGTCCGGCAGATCCGACAATCACGGCGGAGGATCCGATATC

  CAGCTGACCCAGAGCCCTAGCAGCCTGTCTGCCAGCGTGGGCGACAGAGT

  GACCATCACCTGTAGAGCCAGCGAGAGCGTGGACGCTTACGGCATCAGCT

  TCATGAACTGGTTCCAGCAGAAGCCCGGCAAGGCCCCCAAGCTGCTGATC

  TACGCCGCCAGCAATCAGGGCAGCGGCGTGCCAAGCAGATTTTCCGGCTC

  TGGCAGCGGCACCGACTTCACCCTGACCATCAGCAGCATGCAGCCCGAGG

  ACTTCGCCACCTACTACTGCCAGCAGAGCAAGGACGTGCCCTGGACCTTT

  GGCCAGGGTACCAAGCTGGAAATCAAG]

  [Spacer (SEQ ID NO: 362)]

  [PD-1 1.5 PD014 2001 (SEQ ID NO: 957)]

  (SEQ ID NO: 253)

  [QGQSGQG][MSHCWMFSSSCDGVKGGGSSGGSISSGLLSGRSDNHGGGS

  DIQLTQSPSSLSASVGDRVTITCRASESVDAYGISFMNWFQQKPGKAPKL

  LIYAASNQGSGVPSRFSGSGSGTDFTLTISSMQPEDFATYYCQQSKDVPW

  TFGQGTKLEIK]

  PD-1 1.5 PD014 2001 Amino Acid Sequence:

  (SEQ ID NO: 1058)

  MSHCWMFSSSCDGVKGGGSSGGSISSGLLSGRSDNHGGGSDIQLTQSPSS

  LSASVGDRVTITCRASESVDAYGISFMNWFQQKPGKAPKLLIYAASNQGS

  GVPSRFSGSGSGTDFTLTISSMQPEDFATYYCQQSKDVPWTFGQGTKLEI

  K

  [Spacer (SEQ ID NO: 918)]

  [PD-1 1.5 PD014 2001 (SEQ ID NO: 958)]

  (SEQ ID NO: 254)

  [CAAGGCCAGTCTGGCCAAGGT][ATGAGTCATTGCTGGATGTTTTCGAG

  TTCTTGCGATGGGGTGAAGGGAGGTGGCTCGAGCGGCGGCTCTATCTCTT

  CCGGACTGCTGTCCGGCAGATCCGACAATCACGGCGGAGGATCCGATATC

  CAGCTGACCCAGAGCCCTAGCAGCCTGTCTGCCAGCGTGGGCGACAGAGT

  GACCATCACCTGTAGAGCCAGCGAGAGCGTGGACGCTTACGGCATCAGCT

  TCATGAACTGGTTCCAGCAGAAGCCCGGCAAGGCCCCCAAGCTGCTGATC

  TACGCCGCCAGCAATCAGGGCAGCGGCGTGCCAAGCAGATTTTCCGGCTC

  TGGCAGCGGCACCGACTTCACCCTGACCATCAGCAGCATGCAGCCCGAGG

  ACTTCGCCACCTACTACTGCCAGCAGAGCAAGGACGTGCCCTGGACCTTT

  GGCCAGGGTACCAAGCTGGAAATCAAG]

  [Spacer (SEQ ID NO: 362)]

  [PD-1 1.5 PD015 2001 (SEQ ID NO: 959)]

  (SEQ ID NO: 255)

  [QGQSGQG][VSYCTWLIEVTCLRGGGGSSGGSISSGLLSGRSDNHGGGS

  DIQLTQSPSSLSASVGDRVTITCRASESVDAYGISFMNWFQQKPGKAPKL

  LIYAASNQGSGVPSRFSGSGSGTDFTLTISSMQPEDFATYYCQQSKDVPW

  TFGQGTKLEIK]

  PD-1 1.5 PD015 2001 Amino Acid Sequence:

  (SEQ ID NO: 1059)

  VSYCTWLIEVTCLRGGGGSSGGSISSGLLSGRSDNHGGGSDIQLTQSPSS

  LSASVGDRVTITCRASESVDAYGISFMNWFQQKPGKAPKLLIYAASNQGS

  GVPSRFSGSGSGTDFTLTISSMQPEDFATYYCQQSKDVPWTFGQGTKLEI

  K

  [Spacer (SEQ ID NO: 918)]

  [PD-1 1.5 PD015 2001 (SEQ ID NO: 960)]

  (SEQ ID NO: 256)

  [CAAGGCCAGTCTGGCCAAGGT][GTTTCGTATTGCACGTGGTTGATTGA

  GGTGACTTGCCTGAGGGGTGGAGGTGGCTCGAGCGGCGGCTCTATCTCTT

  CCGGACTGCTGTCCGGCAGATCCGACAATCACGGCGGAGGATCCGATATC

  CAGCTGACCCAGAGCCCTAGCAGCCTGTCTGCCAGCGTGGGCGACAGAGT

  GACCATCACCTGTAGAGCCAGCGAGAGCGTGGACGCTTACGGCATCAGCT

  TCATGAACTGGTTCCAGCAGAAGCCCGGCAAGGCCCCCAAGCTGCTGATC

  TACGCCGCCAGCAATCAGGGCAGCGGCGTGCCAAGCAGATTTTCCGGCTC

  TGGCAGCGGCACCGACTTCACCCTGACCATCAGCAGCATGCAGCCCGAGG

  ACTTCGCCACCTACTACTGCCAGCAGAGCAAGGACGTGCCCTGGACCTTT

  GGCCAGGGTACCAAGCTGGAAATCAAG]

  [Spacer (SEQ ID NO: 362)]

  [PD-1 1.5 PD016 2001 (SEQ ID NO: 961)]

  (SEQ ID NO: 257)

  [QGQSGQG][VLCAAYALSSGICGGGGGSSGGSISSGLLSGRSDNHGGGS

  DIQLTQSPSSLSASVGDRVTITCRASESVDAYGISFMNWFQQKPGKAPKL

  LIYAASNQGSGVPSRFSGSGSGTDFTLTISSMQPEDFATYYCQQSKDVPW

  TFGQGTKLEIK]

  PD-1 1.5 PD016 2001 Amino Acid Sequence:

  (SEQ ID NO: 1060)

  VLCAAYALSSGICGGGGGSSGGSISSGLLSGRSDNHGGGSDIQLTQSPSS

  LSASVGDRVTITCRASESVDAYGISFMNWFQQKPGKAPKLLIYAASNQGS

  GVPSRFSGSGSGTDFTLTISSMQPEDFATYYCQQSKDVPWTFGQGTKLEI

  K

  [Spacer (SEQ ID NO: 918)]

  [PD-1 1.5 PD016 2001 (SEQ ID NO: 962)]

  (SEQ ID NO: 258)

  [CAAGGCCAGTCTGGCCAAGGT][GTTTTGTGCGCTGCTTATGCTTTGAG

  TTCGGGTATTTGCGGTGGGGGAGGTGGCTCGAGCGGCGGCTCTATCTCTT

  CCGGACTGCTGTCCGGCAGATCCGACAATCACGGCGGAGGATCCGATATC

  CAGCTGACCCAGAGCCCTAGCAGCCTGTCTGCCAGCGTGGGCGACAGAGT

  GACCATCACCTGTAGAGCCAGCGAGAGCGTGGACGCTTACGGCATCAGCT

  TCATGAACTGGTTCCAGCAGAAGCCCGGCAAGGCCCCCAAGCTGCTGATC

  TACGCCGCCAGCAATCAGGGCAGCGGCGTGCCAAGCAGATTTTCCGGCTC

  TGGCAGCGGCACCGACTTCACCCTGACCATCAGCAGCATGCAGCCCGAGG

  ACTTCGCCACCTACTACTGCCAGCAGAGCAAGGACGTGCCCTGGACCTTT

  GGCCAGGGTACCAAGCTGGAAATCAAG]

  [Spacer (SEQ ID NO: 362)]

  [PD-1 1.5 PD017 2001 (SEQ ID NO: 963)]

  (SEQ ID NO: 259)

  [QGQSGQG][TTCNLYQQSSMFCNAGGGSSGGSISSGLLSGRSDNHGGGS

  DIQLTQSPSSLSASVGDRVTITCRASESVDAYGISFMNWFQQKPGKAPKL

  LIYAASNQGSGVPSRFSGSGSGTDFTLTISSMQPEDFATYYCQQSKDVPW

  TFGQGTKLEIK]

  PD-1 1.5 PD017 2001 Amino Acid Sequence:

  (SEQ ID NO: 1061)

  TTCNLYQQSSMFCNAGGGSSGGSISSGLLSGRSDNHGGGSDIQLTQSPSS

  LSASVGDRVTITCRASESVDAYGISFMNWFQQKPGKAPKLLIYAASNQGS

  GVPSRFSGSGSGTDFTLTISSMQPEDFATYYCQQSKDVPWTFGQGTKLEI

  K

  [Spacer (SEQ ID NO: 918)]

  [PD-1 1.5 PD017 2001 (SEQ ID NO: 964)]

  (SEQ ID NO: 260)

  [CAAGGCCAGTCTGGCCAAGGT][ACGACTTGCAATCTGTATCAGCAGTC

  TTCTATGTTTTGCAATGCTGGAGGTGGCTCGAGCGGCGGCTCTATCTCTT

  CCGGACTGCTGTCCGGCAGATCCGACAATCACGGCGGAGGATCCGATATC

  CAGCTGACCCAGAGCCCTAGCAGCCTGTCTGCCAGCGTGGGCGACAGAGT

  GACCATCACCTGTAGAGCCAGCGAGAGCGTGGACGCTTACGGCATCAGCT

  TCATGAACTGGTTCCAGCAGAAGCCCGGCAAGGCCCCCAAGCTGCTGATC

  TACGCCGCCAGCAATCAGGGCAGCGGCGTGCCAAGCAGATTTTCCGGCTC

  TGGCAGCGGCACCGACTTCACCCTGACCATCAGCAGCATGCAGCCCGAGG

  ACTTCGCCACCTACTACTGCCAGCAGAGCAAGGACGTGCCCTGGACCTTT

  GGCCAGGGTACCAAGCTGGAAATCAAG]

  [Spacer (SEQ ID NO: 362)]

  [PD-1 1.5 PD018 2001 (SEQ ID NO: 965)]

  (SEQ ID NO: 261)

  [QGQSGQG][APRCYMFASYCKSQYGGGSSGGSISSGLLSGRSDNHGGGS

  DIQLTQSPSSLSASVGDRVTITCRASESVDAYGISFMNWFQQKPGKAPKL

  LIYAASNQGSGVPSRFSGSGSGTDFTLTISSMQPEDFATYYCQQSKDVPW

  TFGQGTKLEIK]

  PD-1 1.5 PD018 2001 Amino Acid Sequence:

  (SEQ ID NO: 1062)

  APRCYMFASYCKSQYGGGSSGGSISSGLLSGRSDNHGGGSDIQLTQSPSS

  LSASVGDRVTITCRASESVDAYGISFMNWFQQKPGKAPKLLIYAASNQGS

  GVPSRFSGSGSGTDFTLTISSMQPEDFATYYCQQSKDVPWTFGQGTKLEI

  K]

  [Spacer (SEQ ID NO: 918)]

  [PD-1 1.5 PD018 2001 (SEQ ID NO: 966)]

  (SEQ ID NO: 262)

  [CAAGGCCAGTCTGGCCAAGGT][GCGCCTAGGTGCTATATGTTTGCGTC

  GTATTGCAAGAGTCAGTATGGAGGTGGCTCGAGCGGCGGCTCTATCTCTT

  CCGGACTGCTGTCCGGCAGATCCGACAATCACGGCGGAGGATCCGATATC

  CAGCTGACCCAGAGCCCTAGCAGCCTGTCTGCCAGCGTGGGCGACAGAGT

  GACCATCACCTGTAGAGCCAGCGAGAGCGTGGACGCTTACGGCATCAGCT

  TCATGAACTGGTTCCAGCAGAAGCCCGGCAAGGCCCCCAAGCTGCTGATC

  TACGCCGCCAGCAATCAGGGCAGCGGCGTGCCAAGCAGATTTTCCGGCTC

  TGGCAGCGGCACCGACTTCACCCTGACCATCAGCAGCATGCAGCCCGAGG

  ACTTCGCCACCTACTACTGCCAGCAGAGCAAGGACGTGCCCTGGACCTTT

  GGCCAGGGTACCAAGCTGGAAATCAAG]

  [Spacer (SEQ ID NO: 362)]

  [PD-1 1.5 PD019 2001 (SEQ ID NO: 967)]

  (SEQ ID NO: 263)

  [PD-1 1.5 PD019 2001 (SEQ ID NO: 967)]

  [QGQSGQG][PCDQNPYFYPYVCHAGGGSSGGSISSGLLSGRSDNHGGGS

  DIQLTQSPSSLSASVGDRVTITCRASESVDAYGISFMNWFQQKPGKAPKL

  LIYAASNQGSGVPSRFSGSGSGTDFTLTISSMQPEDFATYYCQQSKDVPW

  TFGQGTKLEIK]

  PD-1 1.5 PD019 2001 Amino Acid Sequence:

  (SEQ ID NO: 967)

  PCDQNPYFYPYVCHAGGGSSGGSISSGLLSGRSDNHGGGSDIQLTQSPSS

  LSASVGDRVTITCRASESVDAYGISFMNWFQQKPGKAPKLLIYAASNQGS

  GVPSRFSGSGSGTDFTLTISSMQPEDFATYYCQQSKDVPWTFGQGTKLEI

  K

  [Spacer (SEQ ID NO: 918)]

  [PD-1 1.5 PD019 2001 (SEQ ID NO: 968)]

  (SEQ ID NO: 264)

  [CAAGGCCAGTCTGGCCAAGGT][CCTTGCGATCAGAATCCGTATTTTTA

  TCCGTATGTGTGCCATGCGGGAGGTGGCTCGAGCGGCGGCTCTATCTCTT

  CCGGACTGCTGTCCGGCAGATCCGACAATCACGGCGGAGGATCCGATATC

  CAGCTGACCCAGAGCCCTAGCAGCCTGTCTGCCAGCGTGGGCGACAGAGT

  GACCATCACCTGTAGAGCCAGCGAGAGCGTGGACGCTTACGGCATCAGCT

  TCATGAACTGGTTCCAGCAGAAGCCCGGCAAGGCCCCCAAGCTGCTGATC

  TACGCCGCCAGCAATCAGGGCAGCGGCGTGCCAAGCAGATTTTCCGGCTC

  TGGCAGCGGCACCGACTTCACCCTGACCATCAGCAGCATGCAGCCCGAGG

  ACTTCGCCACCTACTACTGCCAGCAGAGCAAGGACGTGCCCTGGACCTTT

  GGCCAGGGTACCAAGCTGGAAATCAAG]

  PD-1 1.5 PD019 2001 Nucleic Acid Sequence:

  (SEQ ID NO: 968)

  CCTTGCGATCAGAATCCGTATTTTTATCCGTATGTGTGCCATGCGGGAGG

  TGGCTCGAGCGGCGGCTCTATCTCTTCCGGACTGCTGTCCGGCAGATCCG

  ACAATCACGGCGGAGGATCCGATATCCAGCTGACCCAGAGCCCTAGCAGC

  CTGTCTGCCAGCGTGGGCGACAGAGTGACCATCACCTGTAGAGCCAGCGA

  GAGCGTGGACGCTTACGGCATCAGCTTCATGAACTGGTTCCAGCAGAAGC

  CCGGCAAGGCCCCCAAGCTGCTGATCTACGCCGCCAGCAATCAGGGCAGC

  GGCGTGCCAAGCAGATTTTCCGGCTCTGGCAGCGGCACCGACTTCACCCT

  GACCATCAGCAGCATGCAGCCCGAGGACTTCGCCACCTACTACTGCCAGC

  AGAGCAAGGACGTGCCCTGGACCTTTGGCCAGGGTACCAAGCTGGAAATC

  AAG

  [Spacer (SEQ ID NO: 362)]

  [PD-1 1.5 PD020 2001 (SEQ ID NO: 969)]

  (SEQ ID NO: 265)

  [QGQSGQG][SVCPMYALSSMLCGAGGGSSGGSISSGLLSGRSDNHGGGS

  DIQLTQSPSSLSASVGDRVTITCRASESVDAYGISFMNWFQQKPGKAPKL

  LIYAASNQGSGVPSRFSGSGSGTDFTLTISSMQPEDFATYYCQQSKDVPW

  TFGQGTKLEIK]

  PD-1 1.5 PD020 2001 Amino Acid Sequence:

  (SEQ ID NO: 1063)

  SVCPMYALSSMLCGAGGGSSGGSISSGLLSGRSDNHGGGSDIQLTQSPSS

  LSASVGDRVTITCRASESVDAYGISFMNWFQQKPGKAPKLLIYAASNQGS

  GVPSRFSGSGSGTDFTLTISSMQPEDFATYYCQQSKDVPWTFGQGTKLEI

  K

  [Spacer (SEQ ID NO: 918)]

  [PD-1 1.5 PD020 2001 (SEQ ID NO: 970)]

  (SEQ ID NO: 266)

  [CAAGGCCAGTCTGGCCAAGGT][TCTGTGTGCCCTATGTATGCGTTGAG

  TTCTATGTTGTGCGGTGCGGGAGGTGGCTCGAGCGGCGGCTCTATCTCTT

  CCGGACTGCTGTCCGGCAGATCCGACAATCACGGCGGAGGATCCGATATC

  CAGCTGACCCAGAGCCCTAGCAGCCTGTCTGCCAGCGTGGGCGACAGAGT

  GACCATCACCTGTAGAGCCAGCGAGAGCGTGGACGCTTACGGCATCAGCT

  TCATGAACTGGTTCCAGCAGAAGCCCGGCAAGGCCCCCAAGCTGCTGATC

  TACGCCGCCAGCAATCAGGGCAGCGGCGTGCCAAGCAGATTTTCCGGCTC

  TGGCAGCGGCACCGACTTCACCCTGACCATCAGCAGCATGCAGCCCGAGG

  ACTTCGCCACCTACTACTGCCAGCAGAGCAAGGACGTGCCCTGGACCTTT

  GGCCAGGGTACCAAGCTGGAAATCAAG]

  [Spacer (SEQ ID NO: 362)]

  [PD-1 1.5 PD021 2001 (SEQ ID NO: 971)]

  (SEQ ID NO: 267)

  [QGQSGQG][LSVECYVFSRCSSLPGGGSSGGSISSGLLSGRSDNHGGGS

  DIQLTQSPSSLSASVGDRVTITCRASESVDAYGISFMNWFQQKPGKAPKL

  LIYAASNQGSGVPSRFSGSGSGTDFTLTISSMQPEDFATYYCQQSKDVPW

  TFGQGTKLEIK]

  PD-1 1.5 PD021 2001 Amino Acid Sequence:

  (SEQ ID NO: 1064)

  LSVECYVFSRCSSLPGGGSSGGSISSGLLSGRSDNHGGGSDIQLTQSPSS

  LSASVGDRVTITCRASESVDAYGISFMNWFQQKPGKAPKLLIYAASNQGS

  GVPSRFSGSGSGTDFTLTISSMQPEDFATYYCQQSKDVPWTFGQGTKLEI

  K]

  [Spacer (SEQ ID NO: 918)]

  [PD-1 1.5 PD021 2001 (SEQ ID NO: 972)]

  (SEQ ID NO: 268)

  [CAAGGCCAGTCTGGCCAAGGT][TTGTCTGTGGAGTGCTATGTGTTTTC

  GCGGTGCAGTAGTCTGCCGGGAGGTGGCTCGAGCGGCGGCTCTATCTCTT

  CCGGACTGCTGTCCGGCAGATCCGACAATCACGGCGGAGGATCCGATATC

  CAGCTGACCCAGAGCCCTAGCAGCCTGTCTGCCAGCGTGGGCGACAGAGT

  GACCATCACCTGTAGAGCCAGCGAGAGCGTGGACGCTTACGGCATCAGCT

  TCATGAACTGGTTCCAGCAGAAGCCCGGCAAGGCCCCCAAGCTGCTGATC

  TACGCCGCCAGCAATCAGGGCAGCGGCGTGCCAAGCAGATTTTCCGGCTC

  TGGCAGCGGCACCGACTTCACCCTGACCATCAGCAGCATGCAGCCCGAGG

  ACTTCGCCACCTACTACTGCCAGCAGAGCAAGGACGTGCCCTGGACCTTT

  GGCCAGGGTACCAAGCTGGAAATCAAG]

  [Spacer (SEQ ID NO: 362)]

  [PD-1 1.5 PD022 2001 (SEQ ID NO: 973)]

  (SEQ ID NO: 269)

  [QGQSGQG][FYCTYLVSLTCHPQGGGSSGGSISSGLLSGRSDNHGGGSD

  IQLTQSPSSLSASVGDRVTITCRASESVDAYGISFMNWFQQKPGKAPKLL

  IYAASNQGSGVPSRFSGSGSGTDFTLTISSMQPEDFATYYCQQSKDVPWT

  FGQGTKLEIK]

  PD-1 1.5 PD022 2001 Amino Acid Sequence:

  (SEQ ID NO: 1065)

  FYCTYLVSLTCHPQGGGSSGGSISSGLLSGRSDNHGGGSDIQLTQSPSSL

  SASVGDRVTITCRASESVDAYGISFMNWFQQKPGKAPKLLIYAASNQGSG

  VPSRFSGSGSGTDFTLTISSMQPEDFATYYCQQSKDVPWTFGQGTKLEIK

  [Spacer (SEQ ID NO: 918)]

  [PD-1 1.5 PD022 2001 (SEQ ID NO: 974)]

  (SEQ ID NO: 270)

  [CAAGGCCAGTCTGGCCAAGGT][TTTTATTGCACTTATTTGGTGTCTTT

  GACTTGCCATCCGCAGGGAGGTGGCTCGAGCGGCGGCTCTATCTCTTCCG

  GACTGCTGTCCGGCAGATCCGACAATCACGGCGGAGGATCCGATATCCAG

  CTGACCCAGAGCCCTAGCAGCCTGTCTGCCAGCGTGGGCGACAGAGTGAC

  CATCACCTGTAGAGCCAGCGAGAGCGTGGACGCTTACGGCATCAGCTTCA

  TGAACTGGTTCCAGCAGAAGCCCGGCAAGGCCCCCAAGCTGCTGATCTAC

  GCCGCCAGCAATCAGGGCAGCGGCGTGCCAAGCAGATTTTCCGGCTCTGG

  CAGCGGCACCGACTTCACCCTGACCATCAGCAGCATGCAGCCCGAGGACT

  TCGCCACCTACTACTGCCAGCAGAGCAAGGACGTGCCCTGGACCTTTGGC

  CAGGGTACCAAGCTGGAAATCAAG]

  [Spacer (SEQ ID NO: 362)]

  [PD-1 1.5 PD023 2001 (SEQ ID NO: 975)]

  (SEQ ID NO: 271)

  [QGQSGQG][SMAGCQWSSFCVQRDGGGSSGGSISSGLLSGRSDNHGGGS

  DIQLTQSPSSLSASVGDRVTITCRASESVDAYGISFMNWFQQKPGKAPKL

  LIYAASNQGSGVPSRFSGSGSGTDFTLTISSMQPEDFATYYCQQSKDVPW

  TFGQGTKLEIK]

  PD-1 1.5 PD023 2001 Amino Acid Sequence:

  (SEQ ID NO: 1066)

  SMAGCQWSSFCVQRDGGGSSGGSISSGLLSGRSDNHGGGSDIQLTQSPSS

  LSASVGDRVTITCRASESVDAYGISFMNWFQQKPGKAPKLLIYAASNQGS

  GVPSRFSGSGSGTDFTLTISSMQPEDFATYYCQQSKDVPWTFGQGTKLEI

  K

  [Spacer (SEQ ID NO: 918)]

  [PD-1 1.5 PD023 2001 (SEQ ID NO: 976)]

  (SEQ ID NO: 272)

  [CAAGGCCAGTCTGGCCAAGGT][TCTATGGCGGGTTGCCAGTGGAGTTC

  GTTTTGCGTGCAGCGGGATGGAGGTGGCTCGAGCGGCGGCTCTATCTCTT

  CCGGACTGCTGTCCGGCAGATCCGACAATCACGGCGGAGGATCCGATATC

  CAGCTGACCCAGAGCCCTAGCAGCCTGTCTGCCAGCGTGGGCGACAGAGT

  GACCATCACCTGTAGAGCCAGCGAGAGCGTGGACGCTTACGGCATCAGCT

  TCATGAACTGGTTCCAGCAGAAGCCCGGCAAGGCCCCCAAGCTGCTGATC

  TACGCCGCCAGCAATCAGGGCAGCGGCGTGCCAAGCAGATTTTCCGGCTC

  TGGCAGCGGCACCGACTTCACCCTGACCATCAGCAGCATGCAGCCCGAGG

  ACTTCGCCACCTACTACTGCCAGCAGAGCAAGGACGTGCCCTGGACCTTT

  GGCCAGGGTACCAAGCTGGAAATCAAG]

  [Spacer (SEQ ID NO: 362)]

  [PD-1 1.5 PD024 2001 (SEQ ID NO: 977)]

  (SEQ ID NO: 273)

  [QGQSGQG][IYSCYMFASRCTSDKGGGSSGGSISSGLLSGRSDNHGGGS

  DIQLTQSPSSLSASVGDRVTITCRASESVDAYGISFMNWFQQKPGKAPKL

  LIYAASNQGSGVPSRFSGSGSGTDFTLTISSMQPEDFATYYCQQSKDVPW

  TFGQGTKLEIK]

  PD-1 1.5 PD024 2001 Amino Acid Sequence:

  (SEQ ID NO: 1067)

  IYSCYMFASRCTSDKGGGSSGGSISSGLLSGRSDNHGGGSDIQLTQSPSS

  LSASVGDRVTITCRASESVDAYGISFMNWFQQKPGKAPKLLIYAASNQGS

  GVPSRFSGSGSGTDFTLTISSMQPEDFATYYCQQSKDVPWTFGQGTKLEI

  K]

  [Spacer (SEQ ID NO: 918)]

  [PD-1 1.5 PD024 2001 (SEQ ID NO: 978)]

  (SEQ ID NO: 274)

  [CAAGGCCAGTCTGGCCAAGGT][ATTTATTCGTGCTATATGTTTGCTTC

  GCGGTGCACGTCTGATAAGGGAGGTGGCTCGAGCGGCGGCTCTATCTCTT

  CCGGACTGCTGTCCGGCAGATCCGACAATCACGGCGGAGGATCCGATATC

  CAGCTGACCCAGAGCCCTAGCAGCCTGTCTGCCAGCGTGGGCGACAGAGT

  GACCATCACCTGTAGAGCCAGCGAGAGCGTGGACGCTTACGGCATCAGCT

  TCATGAACTGGTTCCAGCAGAAGCCCGGCAAGGCCCCCAAGCTGCTGATC

  TACGCCGCCAGCAATCAGGGCAGCGGCGTGCCAAGCAGATTTTCCGGCTC

  TGGCAGCGGCACCGACTTCACCCTGACCATCAGCAGCATGCAGCCCGAGG

  ACTTCGCCACCTACTACTGCCAGCAGAGCAAGGACGTGCCCTGGACCTTT

  GGCCAGGGTACCAAGCTGGAAATCAAG]

  [Spacer (SEQ ID NO: 362)]

  [PD-1 1.5 PD002 3001 (SEQ ID NO: 979)]

  (SEQ ID NO: 275)

  [QGQSGQG][DVNCAIWYSVCTTVPGGGSSGGAVGLLAPPGGLSGRSDNH

  GGSDIQLTQSPSSLSASVGDRVTITCRASESVDAYGISFMNWFQQKPGKA

  PKLLIYAASNQGSGVPSRFSGSGSGTDFTLTISSMQPEDFATYYCQQSKD

  VPWTFGQGTKLEIK]

  PD-1 1.5 PD002 3001 Amino Acid Sequence:

  (SEQ ID NO: 1068)

  DVNCAIWYSVCTTVPGGGSSGGAVGLLAPPGGLSGRSDNHGGSDIQLTQS

  PSSLSASVGDRVTITCRASESVDAYGISFMNWFQQKPGKAPKLLIYAASN

  QGSGVPSRFSGSGSGTDFTLTISSMQPEDFATYYCQQSKDVPWTFGQGTK

  LEIK

  [Spacer (SEQ ID NO: 918)]

  [PD-1 1.5 PD002 3001 (SEQ ID NO: 980)]

  (SEQ ID NO: 276)

  [CAAGGCCAGTCTGGCCAAGGT]CAAGGCCAGTCTGGCCAAGGTGATGTT

  AATTGCGCTATTTGGTATTCGGTGTGCACTACTGTTCCTGGAGGTGGCTC

  GAGCGGCGGCTCTATCTCTTCCGGACTGCTGTCCGGCAGATCCGACAATC

  ACGGCGGAGGATCCGGAGGTGGCTCGAGCGGCGGCGCTGTGGGACTGCTG

  GCTCCTCCTGGTGGCCTGTCTGGCAGATCTGATAACCACGGAGGATCCGA

  TATCCAGCTGACCCAGAGCCCTAGCAGCCTGTCTGCCAGCGTGGGCGACA

  GAGTGACCATCACCTGTAGAGCCAGCGAGAGCGTGGACGCTTACGGCATC

  AGCTTCATGAACTGGTTCCAGCAGAAGCCCGGCAAGGCCCCCAAGCTGCT

  GATCTACGCCGCCAGCAATCAGGGCAGCGGCGTGCCAAGCAGATTTTCCG

  GCTCTGGCAGCGGCACCGACTTCACCCTGACCATCAGCAGCATGCAGCCC

  GAGGACTTCGCCACCTACTACTGCCAGCAGAGCAAGGACGTGCCCTGGAC

  CTTTGGCCAGGGTACCAAGCTGGAAATCAAG]

  [Spacer (SEQ ID NO: 362)]

  [PD-1 1.5 PD-12 3001 (SEQ ID NO: 981)]

  (SEQ ID NO: 277)

  [QGQSGQG][NWLDCQFYSECSVYGGGGSSGGAVGLLAPPGGLSGRSDNH

  GGSDIQLTQSPSSLSASVGDRVTITCRASESVDAYGISFMNWFQQKPGKA

  PKLLIYAASNQGSGVPSRFSGSGSGTDFTLTISSMQPEDFATYYCQQSKD

  VPWTFGQGTKLEIK]

  PD-1 1.5 PD-12 3001 Amino Acid Sequence:

  (SEQ ID NO: 1069)

  NWLDCQFYSECSVYGGGGSSGGAVGLLAPPGGLSGRSDNHGGSDIQLTQS

  PSSLSASVGDRVTITCRASESVDAYGISFMNWFQQKPGKAPKLLIYAASN

  QGSGVPSRFSGSGSGTDFTLTISSMQPEDFATYYCQQSKDVPWTFGQGTK

  LEIK]

  [Spacer (SEQ ID NO: 918)]

  [PD-1 1.5 PD-12 3001 (SEQ ID NO: 982)]

  (SEQ ID NO: 278)

  [CAAGGCCAGTCTGGCCAAGGT][AATTGGTTGGATTGCCAGTTTTATTC

  TGAGTGCTCTGTTTATGGTGGAGGTGGCTCGAGCGGCGGCTCTATCTCTT

  CCGGACTGCTGTCCGGCAGATCCGACAATCACGGCGGAGGATCCGGAGGT

  GGCTCGAGCGGCGGCGCTGTGGGACTGCTGGCTCCTCCTGGTGGCCTGTC

  TGGCAGATCTGATAACCACGGAGGATCCGATATCCAGCTGACCCAGAGCC

  CTAGCAGCCTGTCTGCCAGCGTGGGCGACAGAGTGACCATCACCTGTAGA

  GCCAGCGAGAGCGTGGACGCTTACGGCATCAGCTTCATGAACTGGTTCCA

  GCAGAAGCCCGGCAAGGCCCCCAAGCTGCTGATCTACGCCGCCAGCAATC

  AGGGCAGCGGCGTGCCAAGCAGATTTTCCGGCTCTGGCAGCGGCACCGAC

  TTCACCCTGACCATCAGCAGCATGCAGCCCGAGGACTTCGCCACCTACTA

  CTGCCAGCAGAGCAAGGACGTGCCCTGGACCTTTGGCCAGGGTACCAAGC

  TGGAAATCAAG]

  [Spacer (SEQ ID NO: 362)]

  [PD-1 1.5 PD-16 3001 (SEQ ID NO: 983)]

  (SEQ ID NO: 279)

  [QGQSGQG][VLCAAYALSSGICGGGGGSSGGAVGLLAPPGGLSGRSDNH

  GGSDIQLTQSPSSLSASVGDRVTITCRASESVDAYGISFMNWFQQKPGKA

  PKLLIYAASNQGSGVPSRFSGSGSGTDFTLTISSMQPEDFATYYCQQSKD

  VPWTFGQGTKLEIK]

  PD-1 1.5 PD-16 3001 Amino Acid Sequence:

  (SEQ ID NO: 1070)

  VLCAAYALSSGICGGGGGSSGGAVGLLAPPGGLSGRSDNHGGSDIQLTQS

  PSSLSASVGDRVTITCRASESVDAYGISFMNWFQQKPGKAPKLLIYAASN

  QGSGVPSRFSGSGSGTDFTLTISSMQPEDFATYYCQQSKDVPWTFGQGTK

  LEIK

  [Spacer (SEQ ID NO: 918)]

  [PD-1 1.5 PD-16 3001 (SEQ ID NO: 984)]

  (SEQ ID NO: 280)

  [CAAGGCCAGTCTGGCCAAGGT][GTTTTGTGCGCTGCTTATGCTTTGAG

  TTCGGGTATTTGCGGTGGGGGAGGTGGCTCGAGCGGCGGCTCTATCTCTT

  CCGGACTGCTGTCCGGCAGATCCGACAATCACGGCGGAGGATCCGGAGGT

  GGCTCGAGCGGCGGCGCTGTGGGACTGCTGGCTCCTCCTGGTGGCCTGTC

  TGGCAGATCTGATAACCACGGAGGATCCGATATCCAGCTGACCCAGAGCC

  CTAGCAGCCTGTCTGCCAGCGTGGGCGACAGAGTGACCATCACCTGTAGA

  GCCAGCGAGAGCGTGGACGCTTACGGCATCAGCTTCATGAACTGGTTCCA

  GCAGAAGCCCGGCAAGGCCCCCAAGCTGCTGATCTACGCCGCCAGCAATC

  AGGGCAGCGGCGTGCCAAGCAGATTTTCCGGCTCTGGCAGCGGCACCGAC

  TTCACCCTGACCATCAGCAGCATGCAGCCCGAGGACTTCGCCACCTACTA

  CTGCCAGCAGAGCAAGGACGTGCCCTGGACCTTTGGCCAGGGTACCAAGC

  TGGAAATCAAG]

  [Spacer (SEQ ID NO: 362)]

  [PD-1 1.5 PD025 2001 (SEQ ID NO: 985)]

  (SEQ ID NO: 281)

  [QGQSGQG][SRCSVYEVSSGLCDWGGGSSGGSISSGLLSGRSDNHGGGS

  DIQLTQSPSSLSASVGDRVTITCRASESVDAYGISFMNWFQQKPGKAPKL

  LIYAASNQGSGVPSRFSGSGSGTDFTLTISSMQPEDFATYYCQQSKDVPW

  TFGQGTKLEIK]

  PD-1 1.5 PD025 2001 Amino Acid Sequence:

  (SEQ ID NO: 1071)

  SRCSVYEVSSGLCDWGGGSSGGSISSGLLSGRSDNHGGGSDIQLTQSPSS

  LSASVGDRVTITCRASESVDAYGISFMNWFQQKPGKAPKLLIYAASNQGS

  GVPSRFSGSGSGTDFTLTISSMQPEDFATYYCQQSKDVPWTFGQGTKLEI

  K

  [Spacer (SEQ ID NO: 918)]

  [PD-1 1.5 PD025 2001 (SEQ ID NO: 986)]

  (SEQ ID NO: 282)

  [CAAGGCCAGTCTGGCCAAGGT][TCTCGTTGCTCTGTGTATGAGGTTTC

  GTCGGGGCTGTGCGATTGGGGAGGTGGCTCGAGCGGCGGCTCTATCTCTT

  CCGGACTGCTGTCCGGCAGATCCGACAATCACGGCGGAGGATCCGATATC

  CAGCTGACCCAGAGCCCTAGCAGCCTGTCTGCCAGCGTGGGCGACAGAGT

  GACCATCACCTGTAGAGCCAGCGAGAGCGTGGACGCTTACGGCATCAGCT

  TCATGAACTGGTTCCAGCAGAAGCCCGGCAAGGCCCCCAAGCTGCTGATC

  TACGCCGCCAGCAATCAGGGCAGCGGCGTGCCAAGCAGATTTTCCGGCTC

  TGGCAGCGGCACCGACTTCACCCTGACCATCAGCAGCATGCAGCCCGAGG

  ACTTCGCCACCTACTACTGCCAGCAGAGCAAGGACGTGCCCTGGACCTTT

  GGCCAGGGTACCAAGCTGGAAATCAAG]

  [Spacer (SEQ ID NO: 362)]

  [PD-1 1.5 PD026 2001 (SEQ ID NO: 987)]

  (SEQ ID NO: 283)

  [QGQSGQG][GMCSAYAYSSKLCTIGGGSSGGSISSGLLSGRSDNHGGGS

  DIQLTQSPSSLSASVGDRVTITCRASESVDAYGISFMNWFQQKPGKAPKL

  LIYAASNQGSGVPSRFSGSGSGTDFTLTISSMQPEDFATYYCQQSKDVPW

  TFGQGTKLEIK]

  PD-1 1.5 PD026 2001 Amino Acid Sequence:

  (SEQ ID NO: 1072)

  GMCSAYAYSSKLCTIGGGSSGGSISSGLLSGRSDNHGGGSDIQLTQSPSS

  LSASVGDRVTITCRASESVDAYGISFMNWFQQKPGKAPKLLIYAASNQGS

  GVPSRFSGSGSGTDFTLTISSMQPEDFATYYCQQSKDVPWTFGQGTKLEI

  [Spacer (SEQ ID NO: 918)]

  [PD-1 1.5 PD026 2001 (SEQ ID NO: 988)]

  (SEQ ID NO: 284)

  [CAAGGCCAGTCTGGCCAAGGT][GGGATGTGCTCGGCGTATGCTTATTC

  GAGTAAGTTGTGCACTATTGGAGGTGGCTCGAGCGGCGGCTCTATCTCTT

  CCGGACTGCTGTCCGGCAGATCCGACAATCACGGCGGAGGATCCGATATC

  CAGCTGACCCAGAGCCCTAGCAGCCTGTCTGCCAGCGTGGGCGACAGAGT

  GACCATCACCTGTAGAGCCAGCGAGAGCGTGGACGCTTACGGCATCAGCT

  TCATGAACTGGTTCCAGCAGAAGCCCGGCAAGGCCCCCAAGCTGCTGATC

  TACGCCGCCAGCAATCAGGGCAGCGGCGTGCCAAGCAGATTTTCCGGCTC

  TGGCAGCGGCACCGACTTCACCCTGACCATCAGCAGCATGCAGCCCGAGG

  ACTTCGCCACCTACTACTGCCAGCAGAGCAAGGACGTGCCCTGGACCTTT

  GGCCAGGGTACCAAGCTGGAAATCAAG]

  [Spacer (SEQ ID NO: 362)]

  [PD-1 1.5 PD027 2001 (SEQ ID NO: 989)]

  (SEQ ID NO: 285)

  [QGQSGQG][MTTNTCNLLCQQFLTGGGSSGGSISSGLLSGRSDNHGGGS

  DIQLTQSPSSLSASVGDRVTITCRASESVDAYGISFMNWFQQKPGKAPKL

  LIYAASNQGSGVPSRFSGSGSGTDFTLTISSMQPEDFATYYCQQSKDVPW

  TFGQGTKLEIK]

  PD-1 1.5 PD027 2001 Amino Acid Sequence:

  (SEQ ID NO: 1073)

  MTTNTCNLLCQQFLTGGGSSGGSISSGLLSGRSDNHGGGSDIQLTQSPSS

  LSASVGDRVTITCRASESVDAYGISFMNWFQQKPGKAPKLLIYAASNQGS

  GVPSRFSGSGSGTDFTLTISSMQPEDFATYYCQQSKDVPWTFGQGTKLEI

  K]

  [Spacer (SEQ ID NO: 918)]

  [PD-1 1.5 PD027 2001 (SEQ ID NO: 990)]

  (SEQ ID NO: 286)

  [CAAGGCCAGTCTGGCCAAGGT][ATGACTACGAATACTTGCAATCTGTT

  GTGCCAGCAGTTTTTGACGGGAGGTGGCTCGAGCGGCGGCTCTATCTCTT

  CCGGACTGCTGTCCGGCAGATCCGACAATCACGGCGGAGGATCCGATATC

  CAGCTGACCCAGAGCCCTAGCAGCCTGTCTGCCAGCGTGGGCGACAGAGT

  GACCATCACCTGTAGAGCCAGCGAGAGCGTGGACGCTTACGGCATCAGCT

  TCATGAACTGGTTCCAGCAGAAGCCCGGCAAGGCCCCCAAGCTGCTGATC

  TACGCCGCCAGCAATCAGGGCAGCGGCGTGCCAAGCAGATTTTCCGGCTC

  TGGCAGCGGCACCGACTTCACCCTGACCATCAGCAGCATGCAGCCCGAGG

  ACTTCGCCACCTACTACTGCCAGCAGAGCAAGGACGTGCCCTGGACCTTT

  GGCCAGGGTACCAAGCTGGAAATCAAG]

  [Spacer (SEQ ID NO: 362)]

  [PD-1 1.5 PD028 2001 (SEQ ID NO: 991)]

  (SEQ ID NO: 287)

  [QGQSGQG][FQPCLMFASSCFTSKGGGSSGGSISSGLLSGRSDNHGGGS

  DIQLTQSPSSLSASVGDRVTITCRASESVDAYGISFMNWFQQKPGKAPKL

  LIYAASNQGSGVPSRFSGSGSGTDFTLTISSMQPEDFATYYCQQSKDVPW

  TFGQGTKLEIK]

  PD-1 1.5 PD028 2001 Amino Acid Sequence:

  (SEQ ID NO: 991)

  FQPCLMFASSCFTSKGGGSSGGSISSGLLSGRSDNHGGGSDIQLTQSPSS

  LSASVGDRVTITCRASESVDAYGISFMNWFQQKPGKAPKLLIYAASNQGS

  GVPSRFSGSGSGTDFTLTISSMQPEDFATYYCQQSKDVPWTFGQGTKLEI

  K

  [Spacer (SEQ ID NO: 918)]

  [PD-1 1.5 PD028 2001 (SEQ ID NO: 992)]

  (SEQ ID NO: 288)

  [CAAGGCCAGTCTGGCCAAGGT][TTTCAGCCGTGCCTGATGTTTGCGAG

  TAGTTGCTTTACTAGTAAGGGAGGTGGCTCGAGCGGCGGCTCTATCTCTT

  CCGGACTGCTGTCCGGCAGATCCGACAATCACGGCGGAGGATCCGATATC

  CAGCTGACCCAGAGCCCTAGCAGCCTGTCTGCCAGCGTGGGCGACAGAGT

  GACCATCACCTGTAGAGCCAGCGAGAGCGTGGACGCTTACGGCATCAGCT

  TCATGAACTGGTTCCAGCAGAAGCCCGGCAAGGCCCCCAAGCTGCTGATC

  TACGCCGCCAGCAATCAGGGCAGCGGCGTGCCAAGCAGATTTTCCGGCTC

  TGGCAGCGGCACCGACTTCACCCTGACCATCAGCAGCATGCAGCCCGAGG

  ACTTCGCCACCTACTACTGCCAGCAGAGCAAGGACGTGCCCTGGACCTTT

  GGCCAGGGTACCAAGCTGGAAATCAAG]

  PD-1 1.5 PD028 2001 Nucleic Acid Sequence:

  (SEQ ID NO: 992)

  TTTCAGCCGTGCCTGATGTTTGCGAGTAGTTGCTTTACTAGTAAGGGAGG

  TGGCTCGAGCGGCGGCTCTATCTCTTCCGGACTGCTGTCCGGCAGATCCG

  ACAATCACGGCGGAGGATCCGATATCCAGCTGACCCAGAGCCCTAGCAGC

  CTGTCTGCCAGCGTGGGCGACAGAGTGACCATCACCTGTAGAGCCAGCGA

  GAGCGTGGACGCTTACGGCATCAGCTTCATGAACTGGTTCCAGCAGAAGC

  CCGGCAAGGCCCCCAAGCTGCTGATCTACGCCGCCAGCAATCAGGGCAGC

  GGCGTGCCAAGCAGATTTTCCGGCTCTGGCAGCGGCACCGACTTCACCCT

  GACCATCAGCAGCATGCAGCCCGAGGACTTCGCCACCTACTACTGCCAGC

  AGAGCAAGGACGTGCCCTGGACCTTTGGCCAGGGTACCAAGCTGGAAATC

  AAG

  [Spacer (SEQ ID NO: 362)]

  [PD-1 1.5 PD030 2001 (SEQ ID NO: 993)]

  (SEQ ID NO: 289)

  [QGQSGQG][ALCSMYLASSGLCNKGGGSSGGSISSGLLSGRSDNHGGGS

  DIQLTQSPSSLSASVGDRVTITCRASESVDAYGISFMNWFQQKPGKAPKL

  LIYAASNQGSGVPSRFSGSGSGTDFTLTISSMQPEDFATYYCQQSKDVPW

  TFGQGTKLEIK]

  PD-1 1.5 PD030 2001 Amino Acid Sequence:

  (SEQ ID NO: 1074)

  ALCSMYLASSGLCNKGGGSSGGSISSGLLSGRSDNHGGGSDIQLTQSPSS

  LSASVGDRVTITCRASESVDAYGISFMNWFQQKPGKAPKLLIYAASNQGS

  GVPSRFSGSGSGTDFTLTISSMQPEDFATYYCQQSKDVPWTFGQGTKLEI

  K

  [Spacer (SEQ ID NO: 918)]

  [PD-1 1.5 PD030 2001 (SEQ ID NO: 994)]

  (SEQ ID NO: 290)

  [CAAGGCCAGTCTGGCCAAGGT][GCGCTTTGCAGTATGTATCTTGCTAG

  TTCTGGGCTGTGCAATAAGGGAGGTGGCTCGAGCGGCGGCTCTATCTCTT

  CCGGACTGCTGTCCGGCAGATCCGACAATCACGGCGGAGGATCCGATATC

  CAGCTGACCCAGAGCCCTAGCAGCCTGTCTGCCAGCGTGGGCGACAGAGT

  GACCATCACCTGTAGAGCCAGCGAGAGCGTGGACGCTTACGGCATCAGCT

  TCATGAACTGGTTCCAGCAGAAGCCCGGCAAGGCCCCCAAGCTGCTGATC

  TACGCCGCCAGCAATCAGGGCAGCGGCGTGCCAAGCAGATTTTCCGGCTC

  TGGCAGCGGCACCGACTTCACCCTGACCATCAGCAGCATGCAGCCCGAGG

  ACTTCGCCACCTACTACTGCCAGCAGAGCAAGGACGTGCCCTGGACCTTT

  GGCCAGGGTACCAAGCTGGAAATCAAG]

  [Spacer (SEQ ID NO: 362)]

  [PD-1 1.5 PD033 2001 (SEQ ID NO: 995)]

  (SEQ ID NO: 291)

  [QGQSGQG][EFCARDWLPYQCSSFGGGSSGGSISSGLLSGRSDNHGGGS

  DIQLTQSPSSLSASVGDRVTITCRASESVDAYGISFMNWFQQKPGKAPKL

  LIYAASNQGSGVPSRFSGSGSGTDFTLTISSMQPEDFATYYCQQSKDVPW

  TFGQGTKLEIK]

  PD-1 1.5 PD033 2001 Amino Acid Sequence:

  (SEQ ID NO: 1075)

  EFCARDWLPYQCSSFGGGSSGGSISSGLLSGRSDNHGGGSDIQLTQSPSS

  LSASVGDRVTITCRASESVDAYGISFMNWFQQKPGKAPKLLIYAASNQGS

  GVPSRFSGSGSGTDFTLTISSMQPEDFATYYCQQSKDVPWTFGQGTKLEI

  K]

  [Spacer (SEQ ID NO: 918)]

  [PD-1 1.5 PD033 2001 (SEQ ID NO: 996)]

  (SEQ ID NO: 292)

  [CAAGGCCAGTCTGGCCAAGGT][GAGTTTTGCGCTCGGGATTGGCTGCC

  GTATCAGTGCTCGAGTTTTGGAGGTGGCTCGAGCGGCGGCTCTATCTCTT

  CCGGACTGCTGTCCGGCAGATCCGACAATCACGGCGGAGGATCCGATATC

  CAGCTGACCCAGAGCCCTAGCAGCCTGTCTGCCAGCGTGGGCGACAGAGT

  GACCATCACCTGTAGAGCCAGCGAGAGCGTGGACGCTTACGGCATCAGCT

  TCATGAACTGGTTCCAGCAGAAGCCCGGCAAGGCCCCCAAGCTGCTGATC

  TACGCCGCCAGCAATCAGGGCAGCGGCGTGCCAAGCAGATTTTCCGGCTC

  TGGCAGCGGCACCGACTTCACCCTGACCATCAGCAGCATGCAGCCCGAGG

  ACTTCGCCACCTACTACTGCCAGCAGAGCAAGGACGTGCCCTGGACCTTT

  GGCCAGGGTACCAAGCTGGAAATCAAG]

  [Spacer (SEQ ID NO: 362)]

  [PD-1 1.5 PD034 2001 (SEQ ID NO: 1028)]

  (SEQ ID NO: 1029)

  [QGQSGQG][TSYCSIEHYPCNTHHGGGSSGGSISSGLLSGRSDNHG

  GGSDIQLTQSPSSLSASVGDRVTITCRASESVDAYGISFMNWFQQ

  KPGKAPKLLIYAASNQGSGVPSRFSGSGSGTDFTLTISSMQPEDFATYY

  CQQSKDVPWTFGQGTKLEIK]

  PD-1 1.5 PD034 2001 Amino Acid Sequence:

  (SEQ ID NO: 1028)

  TSYCSIEHYPCNTHHGGGSSGGSISSGLLSGRSDNHGGGSDIQLTQSPS

  SLSASVGDRVTITCRASESVDAYGISFMNWFQQKPGKAPKLLIYAASNQ

  GSGVPSRFSGSGSGTDFTLTISSMQPEDFATYYCQQSKDVPWTFGQGTK

  LEIK

  [Spacer (SEQ ID NO: 918)]

  [PD-1 1.5 PD034 2001 (SEQ ID NO: 1030)

  (SEQ ID NO: 1031)

  [CAAGGCCAGTCTGGCCAAGGT][ACGTCATACTGCAGTATTGAGCAT

  TACCCCTGCAATACACATCATGGAGGTGGCTCGAGCGGCGGCTCTATCTC

  TTCCGGACTGCTGTCCGGCAGATCCGACAATCACGGCGGAGGATCCGATA

  TCCAGCTGACCCAGAGCCCTAGCAGCCTGTCTGCCAGCGTGGGCGACAG

  AGTGACCATCACCTGTAGAGCCAGCGAGAGCGTGGACGCTTACGGCATC

  AGCTTCATGAACTGGTTCCAGCAGAAGCCCGGCAAGGCCCCCAAGCTGC

  TGATCTACGCCGCCAGCAATCAGGGCAGCGGCGTGCCAAGCAGATTTTC

  CGGCTCTGGCAGCGGCACCGACTTCACCCTGACCATCAGCAGCATGCAG

  CCCGAGGACTTCGCCACCTACTACTGCCAGCAGAGCAAGGACGTGCCC

  TGGACCTTTGGCCAGGGTACCAAGCTGGAAATCAAG]

  PD-1 1.5 PD034 2001 Nucleic Acid Sequence:

  (SEQ ID NO: 1030)

  ACGTCATACTGCAGTATTGAGCATTACCCCTGCAATACACATCATGGAG

  GTGGCTCGAGCGGCGGCTCTATCTCTTCCGGACTGCTGTCCGGCAGATC

  CGACAATCACGGCGGAGGATCCGATATCCAGCTGACCCAGAGCCCTAGC

  AGCCTGTCTGCCAGCGTGGGCGACAGAGTGACCATCACCTGTAGAGCCA

  GCGAGAGCGTGGACGCTTACGGCATCAGCTTCATGAACTGGTTCCAGCA

  GAAGCCCGGCAAGGCCCCCAAGCTGCTGATCTACGCCGCCAGCAATCAG

  GGCAGCGGCGTGCCAAGCAGATTTTCCGGCTCTGGCAGCGGCACCGACT

  TCACCCTGACCATCAGCAGCATGCAGCCCGAGGACTTCGCCACCTACTA

  CTGCCAGCAGAGCAAGGACGTGCCCTGGACCTTTGGCCAGGGTACCAAG

  CTGGAAATCAAG

  [Spacer (SEQ ID NO: 362)]

  [PD-1 1.5 PD035 2001 (SEQ ID NO: 997)]

  (SEQ ID NO: 293)

  [QGQSGQG][PYICSSFPLDCQAGQGGGSSGGSISSGLLSGRSDNHGG

  GSDIQLTQSPSSLSASVGDRVTITCRASESVDAYGISFMNWFQQKPGKAP

  KLLIYAASNQGSGVPSRFSGSGSGTDFTLTISSMQPEDFATYYCQQSKDV

  PWTFGQGTKLEIK]

  PD-1 1.5 PD035 2001 Amino Acid Sequence:

  (SEQ ID NO: 1076)

  PYICSSFPLDCQAGQGGGSSGGSISSGLLSGRSDNHGGGSDIQLTQSPS

  SLSASVGDRVTITCRASESVDAYGISFMNWFQQKPGKAPKLLIYAASNQ

  GSGVPSRFSGSGSGTDFTLTISSMQPEDFATYYCQQSKDVPWTFGQGTK

  LEIK]

  [Spacer (SEQ ID NO: 918)]

  [PD-1 1.5 PD035 2001 (SEQ ID NO: 998)]

  (SEQ ID NO: 584)

  [CAAGGCCAGTCTGGCCAAGGT][CCTTATATTTGCTCTAGTTTTCCGTT

  GGATTGCCAGGCGGGTCAGGGAGGTGGCTCGAGCGGCGGCTCTATCTCTT

  CCGGACTGCTGTCCGGCAGATCCGACAATCACGGCGGAGGATCCGATATC

  CAGCTGACCCAGAGCCCTAGCAGCCTGTCTGCCAGCGTGGGCGACAGAG

  TGACCATCACCTGTAGAGCCAGCGAGAGCGTGGACGCTTACGGCATCAG

  CTTCATGAACTGGTTCCAGCAGAAGCCCGGCAAGGCCCCCAAGCTGCTG

  ATCTACGCCGCCAGCAATCAGGGCAGCGGCGTGCCAAGCAGATTTTCCG

  GCTCTGGCAGCGGCACCGACTTCACCCTGACCATCAGCAGCATGCAGCC

  CGAGGACTTCGCCACCTACTACTGCCAGCAGAGCAAGGACGTGCCCTGG

  ACCTTTGGCCAGGGTACCAAGCTGGAAATCAAG]

Example 9: Anti-PD-1 Activatable Antibodies of the Disclosure
• This example demonstrates that anti-PD-1 activatable antibodies of the disclosure can be made in a variety of combinations of MM, CM, VL, and VH domains, as well as in a variety of distinct Ig isotypes. In addition, this example demonstrates that anti-PD-1 activatable antibodies of the disclosure can be made in a variety of combinations of MM, CM, VLCDR1, VLCDR2, VLCDR3, VHCDR1, VHCDR2, and VHCDR3 domains, as well as in a variety of distinct Ig isotypes.

• TABLE 13A
  	VL		VL CDRs	VH CDRs
  	SEQ	VH	SEQ ID NO:	SEQ ID NO:

  Mask Sequence	Substrates:	ID NO:	SEQ ID NO:	CDR1	CDR2	CDR3	CDR1	CDR2	CDR3

  AMSGCSWSAFCPYLA	LSGRSDNH	1	3	653	658	664	669	678	683
  (SEQ ID NO: 66)	(SEQ ID NO: 294)
  DVNCAIWYSVCITVP	TGRGPSWV	5	7	654	659	665	670	679	684
  (SEQ ID NO: 67)	(SEQ ID NO: 295)
  LVCPLYALSSGVCMG	PLTGRSGG	9	11	655	660	666	671	680	685
  (SEQ ID NO: 68)	(SEQ ID NO: 296)
  SVNCRIWSAVCAGYE	TARGPSFK	13	15	656	661	667	672	681	686
  (SEQ ID NO: 69)	(SEQ ID NO: 297)
  MLVCSLQPTAMCERV	NTLSGRSENHSG	17	19	657	662	668	673	682	687
  (SEQ ID NO: 70)	(SEQ ID NO: 298)
  APRCYMFASYCKSQY	NTLSGRSGNHGS	21	39		663		674
  (SEQ ID NO: 71)	(SEQ ID NO: 299)
  VGPCELTPKPVCNTY	TSTSGRSANPRG	23	41				675
  (SEQ ID NO: 72)	(SEQ ID NO: 300)
  ETCNQYERSSGLCFA	TSGRSANP	25	43				676
  (SEQ ID NO: 73)	(SEQ ID NO: 301)
  APRTCYTYQCSSFYT	VHMPLGFLGP	27	45				677
  (SEQ ID NO: 74)	(SEQ ID NO: 302)

  GLCSWYLSSSGLCVD	AVGLLAPP	29	47	VL CDRs of SEQ ID	VH CDRs of SEQ ID
  (SEQ ID NO: 75)	(SEQ ID NO: 303)			NO: 1	NO: 3
  VPWCQLTPRVMCMWA	AQNLLGMV	31	49	VL CDRs of SEQ ID	VH CDRs of SEQ ID
  (SEQ ID NO: 76)	(SEQ ID NO: 304)			NO: 5	NO: 7
  NWLDCQFYSECSVYG	QNQALRMA	33	51	VL CDRs of SEQ ID	VH CDRs of SEQ ID
  (SEQ ID NO: 77)	(SEQ ID NO: 305)			NO: 9	NO: 11
  SCPLYVMSSFGGCWD	LAAPLGLL	35	53	VL CDRs of SEQ ID	VH CDRs of SEQ ID
  (SEQ ID NO: 78)	(SEQ ID NO: 306)			NO: 13	NO: 15
  MSHCWMFSSSCDGVK	STFPFGMF	37	55	VL CDRs of SEQ ID	VH CDRs of SEQ ID
  (SEQ ID NO: 79)	(SEQ ID NO: 307)			NO: 17	NO: 19
  VSYCTWLIEVICLRG	ISSGLLSS		57	VL CDRs of SEQ ID	VH CDRs of SEQ ID
  (SEQ ID NO: 80)	(SEQ ID NO: 308)			NO: 21	NO: 39
  VLCAAYALSSGICGG	PAGLWLDP		59	VL CDRs of SEQ ID	VH CDRs of SEQ ID
  (SEQ ID NO: 81)	(SEQ ID NO: 309)			NO: 23	NO: 41
  TTCNLYQQSSMFCNA	VAGRSMRP			VL CDRs of SEQ ID	VH CDRs of SEQ ID
  (SEQ ID NO: 82)	(SEQ ID NO: 310)			NO: 25	NO: 43
  APRCYMFASYCKSQY	VVPEGRRS			VL CDRs of SEQ ID	VH CDRs of SEQ ID
  (SEQ ID NO: 83)	(SEQ ID NO: 311)			NO: 27	NO: 45
  PCDQNPYFYPYVCHA	ILPRSPAF			VL CDRs of SEQ ID	VH CDRs of SEQ ID
  (SEQ ID NO: 84)	(SEQ ID NO: 312)			NO: 29	NO: 47
  SVCPMYALSSMLCGA	MVLGRSLL			VL CDRs of SEQ ID	VH CDRs of SEQ ID
  (SEQ ID NO: 85)	(SEQ ID NO: 313)			NO: 31	NO: 49
  LSVECYVFSRCSSLP	QGRAITFI			VL CDRs of SEQ ID	VH CDRs of SEQ ID
  (SEQ ID NO: 86)	(SEQ ID NO: 314)			NO: 33	NO: 51
  FYCTYLVSLTCHPQ	SPRSIMLA			VL CDRs of SEQ ID	VH CDRs of SEQ ID
  (SEQ ID NO: 87)	(SEQ ID NO: 315)			NO: 35	NO: 53
  SMAGCQWSSFCVQRD	SMLRSMPL			VL CDRs of SEQ ID	VH CDRs of SEQ ID
  (SEQ ID NO: 88)	(SEQ ID NO: 316)			NO: 37	NO: 55
  IYSCYMFASRCTSDK	SARGPSRW				VH CDRs of SEQ ID
  (SEQ ID NO: 89)	(SEQ ID NO: 319)				NO: 57
  SRCSVYEVSSGLCDW	GWHTGRN				VH CDRs of SEQ ID
  (SEQ ID NO: 90)	(SEQ ID NO: 320)				NO: 59
  GMCSAYAYSSKLCTI	HTGRSGAL			LC CDRs of SEQ ID	HC CDRs of SEQ ID
  (SEQ ID NO: 91)	(SEQ ID NO: 321)			NO: 543	NO: 546
  MTTNTCNLLCQQFLT	AARGPAIH
  (SEQ ID NO: 92)	(SEQ ID NO: 322)
  FQPCLMFASSCFTSK	RGPAFNPM
  (SEQ ID NO: 93)	(SEQ ID NO: 323)
  WNCHPAGVGPVFCEV	SSRGPAYL
  (SEQ ID NO: 94)	(SEQ ID NO: 324)
  ALCSMYLASSGLCNK	RGPATPIM
  (SEQ ID NO: 95)	(SEQ ID NO: 325)
  NYLSCQFFQNCYETY	RGPA
  (SEQ ID NO: 96)	(SEQ ID NO: 326)
  GWCLFSDMWLGLCSA	GGQPSGMWGW
  (SEQ ID NO: 97)	(SEQ ID NO: 327)
  EFCARDWLPYQCSSF	FPRPLGITGL
  (SEQ ID NO: 98)	(SEQ ID NO: 328)
  TSYCSIEHYPCNTHH	SPLTGRSG
  (SEQ ID NO: 99)	(SEQ ID NO: 329)
  PYICSSFPLDCQAGQ	SAGFSLPA
  (SEQ ID NO: 100)	(SEQ ID NO: 330)
  VGCEWYMSSSGMCSR	LAPLGLQRR
  (SEQ ID NO: 101)	(SEQ ID NO: 331)
  EVCGGCSMQSVSCWP	SGGPLGVR
  (SEQ ID NO: 102)	(SEQ ID NO: 332)
  FTECQLSPKAICMSN	PLGL
  (SEQ ID NO: 103)	(SEQ ID NO: 333)
  KYCLFSEYVEGTCLN	ISSGLSS
  (SEQ ID NO: 104)	(SEQ ID NO: 334)
  SGCPMYAWGWDECWR	PVGYTSSL
  (SEQ ID NO: 105)	(SEQ ID NO: 335)
  VDCPWYASSSAICSR	DWLYWPGI
  (SEQ ID NO: 106)	(SEQ ID NO: 336)
  DMLLCQIRGSCAAWG	LKAAPRWA
  (SEQ ID NO: 107)	(SEQ ID NO: 337)
  ECHPYQASASLWCGY	GPSHLVLT
  (SEQ ID NO: 108)	(SEQ ID NO: 338)
  MMMGCMWSAWCPPSR	LPGGLSPW
  (SEQ ID NO: 109)	(SEQ ID NO: 339)
  NAYFRCSLMCNMIMF	MGLFSEAG
  (SEQ ID NO: 110)	(SEQ ID NO: 340)
  ACCKESVHSVHDCKR	SPLPLRVP
  (SEQ ID NO: 111)	(SEQ ID NO: 341)
  ACIGINSYMSNYCYL	RMHLRSLG
  (SEQ ID NO: 112)	(SEQ ID NO: 342)
  ANCSFLELTNKFCTI	LLAPSHRA
  (SEQ ID NO: 113)	(SEQ ID NO: 343)
  AYCSYLMFASNPCII	GPRSFGL
  (SEQ ID NO: 114)	(SEQ ID NO: 344)
  CFTSKCPCLCYSLLA	GPRSFG
  (SEQ ID NO: 115)	(SEQ ID NO: 345)
  CLCRDINCWLGCSKT	LSGRSGNH
  (SEQ ID NO: 116)	(SEQ ID NO: 1157)
  CWCDIYCSPYQCSSF	SGRSANPRG
  (SEQ ID NO: 117)	(SEQ ID NO: 1158)
  DCIYYYQQSANLCSY	LSGRSDDH
  (SEQ ID NO: 118)	(SEQ ID NO: 1161)
  DCTGVNYYIDKHCIN	LSGRSDIH
  (SEQ ID NO: 119)	(SEQ ID NO: 1162)
  DECHGYLRSSGLCGG	LSGRSDQH
  (SEQ ID NO: 120)	(SEQ ID NO: 1165)
  DICSAYAASSGFCYY	LSGRSDTH
  (SEQ ID NO: 121)	(SEQ ID NO: 1166)
  DIICVLIPTAWCGRT	LSGRSDYH
  (SEQ ID NO: 122)	(SEQ ID NO: 1169)
  DNCCMYCSWWIACRD	LSGRSDNP
  (SEQ ID NO: 123)	(SEQ ID NO: 1520)
  DSCQWYMLSADLCGT	LSGRSANP
  (SEQ ID NO: 124)	(SEQ ID NO: 1695)
  DSVCFSSSSFLCHKS	LSGRSANI
  (SEQ ID NO: 125)	(SEQ ID NO: 1696)
  DTMCAIWWTVCSGGR	LSGRSDNI
  (SEQ ID NO: 126)	(SEQ ID NO: 1697)
  ECTYQTSSFHEACMS	MIAPVAYR
  (SEQ ID NO: 127)	(SEQ ID NO: 1698)
  EGCNLYERSSYGCNN	RPSPMWAY
  (SEQ ID NO: 128)	(SEQ ID NO: 1699)
  EGCTAFAMSAGICGG	WATPRPMR
  (SEQ ID NO: 129)	(SEQ ID NO: 1700)
  EQSCSLTPIAFCWSE	FRLLDWQW
  (SEQ ID NO: 130)	(SEQ ID NO: 1701)
  EWCNAYISSSKLCST	ISSGL
  (SEQ ID NO: 131)	(SEQ ID NO: 1702)
  FEVCYMFASACRNGM	ISSGLLS
  (SEQ ID NO: 132)	(SEQ ID NO: 1703)
  FSCSWYAESSSLCDI	ISSGLL
  (SEQ ID NO: 133)	(SEQ ID NO: 1704)
  FVCQMFEASSGLCGG	ISSGLLSGRSDNH
  (SEQ ID NO: 134)	(SEQ ID NO: 214)
  FYCPCCMFASSCGSR	AVGLLAPPGGLSGRSDNH
  (SEQ ID NO: 135)	(SEQ ID NO: 318)
  FYCSYLPGASHQCSH	ISSGLLSSGGSGGSLSGRSDNH
  (SEQ ID NO: 136)	(SEQ ID NO: 346)
  FYCSYLYMCEVCCYE	ISSGLLSSGGSGGSLSGRSDNH
  (SEQ ID NO: 137)	(SEQ ID NO: 346)
  GFCTQHTVLTWCPTS	AVGLLAPPGGTSTSGRSANPRG
  (SEQ ID NO: 138)	(SEQ ID NO: 347)
  GSCPSYAVSAGLCYA	TSTSGRSANPRGGGAVGLLAPP
  (SEQ ID NO: 139)	(SEQ ID NO: 348)
  GSQCFLTPTAFCTHT	VHMPLGFLGPGGTSTSGRSANPRG
  (SEQ ID NO: 140)	(SEQ ID NO: 349)
  GTCHPYMQSSKICNN	TSTSGRSANPRGGGVHMPLGFLGP
  (SEQ ID NO: 141)	(SEQ ID NO: 350)
  GVECFVFTGGCGGYG	LSGRSDNHGGAVGLLAPP
  (SEQ ID NO: 142)	(SEQ ID NO: 351)
  HELCNGHWVPCCWAY	VHMPLGFLGPGGLSGRSDNH
  (SEQ ID NO: 143)	(SEQ ID NO: 352)
  ICDSYYAVSSGLCLL	LSGRSDNHGGVHMPLGFLGP
  (SEQ ID NO: 144)	(SEQ ID NO: 353)
  IGCAWYVSSAGWCSP	LSGRSDNHGGSGGSISSGLLSS
  (SEQ ID NO: 145)	(SEQ ID NO: 354)
  INLCWMFASECGEHH	LSGRSGNHGGSGGSISSGLLSS
  (SEQ ID NO: 146)	(SEQ ID NO: 355)
  KCWLAEMTNLEHCNM	ISSGLLSSGGSGGSLSGRSGNH
  (SEQ ID NO: 147)	(SEQ ID NO: 356)
  KHCSDFAYSSRLCDR	LSGRSDNHGGSGGSQNQALRMA
  (SEQ ID NO: 148)	(SEQ ID NO: 357)
  KVCSSYASSSGLCGW	QNQALRMAGGSGGSLSGRSDNH
  (SEQ ID NO: 149)	(SEQ ID NO: 358)
  LDS CYMFASYCVQAV	LSGRSGNHGGSGGSQNQALRMA
  (SEQ ID NO: 150)	(SEQ ID NO: 359)
  LLACHPIFVTVCQTR	QNQALRMAGGSGGSLSGRSGNH
  (SEQ ID NO: 151)	(SEQ ID NO: 360)
  LLSCPYNPEHVCHTS	ISSGLLSGRSGNH
  (SEQ ID NO: 152)	(SEQ ID NO: 361)
  LMCSLYALSSNLCGR	ISSGLLSSGGSGGSLSGRNH
  (SEQ ID NO: 153)	(SEQ ID NO: 1091)
  LMWCVLFLWSWCCRI	ISSGLLSGRSANPRG
  (SEQ ID NO: 154)	(SEQ ID NO: 1092)
  LPI CHLTPTAVCTHI	AVGLLAPPTSGRSANPRG
  (SEQ ID NO: 155)	(SEQ ID NO: 1093)
  LSNMCLAFGSCLYAW	AVGLLAPPSGRSANPRG
  (SEQ ID NO: 156)	(SEQ ID NO: 1094)
  LSRCHPIWYTICQNP	ISSGLLSGRSDDH
  (SEQ ID NO: 157)	(SEQ ID NO: 1095)
  LTQCMSVHKECGGYE	ISSGLLSGRSDIH
  (SEQ ID NO: 158)	(SEQ ID NO: 1096)
  LVNCRIWSWVCEEAT	ISSGLLSGRSDQH
  (SEQ ID NO: 159)	(SEQ ID NO: 1097)
  LYCSWYQMSSAVCKE	ISSGLLSGRSDTH
  (SEQ ID NO: 160)	(SEQ ID NO: 1098)
  MECGWYALSARFCEV	ISSGLLSGRSDYH
  (SEQ ID NO: 161)	(SEQ ID NO: 1099)
  MTCSPYAMSAHFCNE	ISSGLLSGRSDNP
  (SEQ ID NO: 162)	(SEQ ID NO: 1100)
  MVCSLYAYSASLCGA	ISSGLLSGRSANP
  (SEQ ID NO: 163)	(SEQ ID NO: 1101)
  NALCWSTFSWWCDMD	ISSGLLSGRSANI
  (SEQ ID NO: 164)	(SEQ ID NO: 1102)
  NFTCMLTPKAYCVQT	AVGLLAPPGGLSGRSDDH
  (SEQ ID NO: 165)	(SEQ ID NO: 1103)
  NGACIFILSWCINKT	AVGLLAPPGGLSGRSDIH
  (SEQ ID NO: 166)	(SEQ ID NO: 1104)
  NGCELYAAASGLCRT	AVGLLAPPGGLSGRSDQH
  (SEQ ID NO: 167)	(SEQ ID NO: 1105)
  NIECSVFGRCCCDNY	AVGLLAPPGGLSGRSDTH
  (SEQ ID NO: 168)	(SEQ ID NO: 1106)
  PACRPMFWNRSCDNI	AVGLLAPPGGLSGRSDYH
  (SEQ ID NO: 169)	(SEQ ID NO: 1107)
  PCRVSNMFFPYNCLD	AVGLLAPPGGLSGRSDNP
  (SEQ ID NO: 170)	(SEQ ID NO: 1108)
  PIMCMLLPESYCWIW	AVGLLAPPGGLSGRSANP
  (SEQ ID NO: 171)	(SEQ ID NO: 1109)
  PQSCYMFASLCMPNG	AVGLLAPPGGLSGRSANI
  (SEQ ID NO: 172)	(SEQ ID NO: 1110)
  PRCPQGLPLYQCSSF	ISSGLLSGRSDNI
  (SEQ ID NO: 173)	(SEQ ID NO: 1111)
  PSVECLVFKRCYALP	AVGLLAPPGGLSGRSDNI
  (SEQ ID NO: 174)	(SEQ ID NO: 1112)
  PVCQRSATIYNCNWF
  (SEQ ID NO: 175)
  QCAAYYISSFGGCSN
  (SEQ ID NO: 176)
  QFGCFMLARDFCGTY
  (SEQ ID NO: 177)
  QMMCPYNPEHKCHQK
  (SEQ ID NO: 178)
  QRECWMFASSCNSKN
  (SEQ ID NO: 179)
  QSNMCITYICSSFNY
  (SEQ ID NO: 180)
  QSRCHSLAPYLCSSF
  (SEQ ID NO: 181)
  RAYCSLLFADSCNNN
  (SEQ ID NO: 182)
  RCIGINQYIDSNCYN
  (SEQ ID NO: 183)
  RLSCFMFASQCALEF
  (SEQ ID NO: 184)
  RQCIILMNHRQCFFK
  (SEQ ID NO: 185)
  RSCTPYMMSSSLCNT
  (SEQ ID NO: 186)
  RYCHYWKMPYECSSF
  (SEQ ID NO: 187)
  SCVSLSWFDMLKCYE
  (SEQ ID NO: 188)
  SDNCEIWWTVCSAAM
  (SEQ ID NO: 189)
  SFCWSYLVSSGLCGV
  (SEQ ID NO: 190)
  SMCMNNYGTTIMCGN
  (SEQ ID NO: 191)
  SMVGCGWSTFCPSRG
  (SEQ ID NO: 192)
  SSLHCANGHTCPFCL
  (SEQ ID NO: 193)
  SVCSYYEESSGICSP
  (SEQ ID NO: 194)
  SWCGWYAASSGVCAL
  (SEQ ID NO: 195)
  TCISQTIDSYLNCVN
  (SEQ ID NO: 196)
  TFCNLYTKSSNICMS
  (SEQ ID NO: 197)
  TYCVFHEYLDNTCNN
  (SEQ ID NO: 198)
  VATGCPNLMLCGSWP
  (SEQ ID NO: 199)
  VEYCSLLLGNRCDYW
  (SEQ ID NO: 200)
  VGCNMYLMSAGLCVD
  (SEQ ID NO: 201)
  VLYCSWDSGTCVGSH
  (SEQ ID NO: 202)
  VMFSCYYLETCAPGV
  (SEQ ID NO: 203)
  VRIGLCPESCLVSGF
  (SEQ ID NO: 204)
  VTCTYYATSSSLCNT
  (SEQ ID NO: 205)
  VTGCILLPKAWCWGD
  (SEQ ID NO: 206)
  VWCSIYEYSSNLCSR
  (SEQ ID NO: 207)
  WMLECQYNNTCNNMT
  (SEQ ID NO: 208)
  WPCSPLEYYNNICNV
  (SEQ ID NO: 209)
  WTYDCHLNQTCPTYY
  (SEQ ID NO: 210)
  YCSINMYLIGGNCMY
  (SEQ ID NO: 211)
  YFCSLYANSAGFCGG
  (SEQ ID NO: 212)
  YVSCYMFSSSCPSTW
  (SEQ ID NO: 213)

• TABLE 13B
  	VL	VH	VL CDRs	VH CDRs
  	SEQ	SEQ	SEQ ID NO:	SEQ ID NO:

  Mask Sequence	Substrates:	ID NO:	ID NO:	CDR1	CDR2	CDR3	CDR1	CDR2	CDR3

  RYCHAANPDRFCGIY	LSGRSDNH	626	1346	VL CDRs of SEQ ID	VH CDRs of SEQ ID
  (SEQ ID NO: 1206)	(SEQ ID NO: 294)			NO: 626	NO: 1346

  PRVCSTDGGDYCLLP	TGRGPSWV			1705	1706	1707	1708	1709	1710
  (SEQ ID NO: 1207)	(SEQ ID NO: 295)
  PRPQCHHRHNCPDHP	PLTGRSGG
  (SEQ ID NO: 1208)	(SEQ ID NO: 296)
  KCSRPAHQNPDRCSR	TARGPSFK
  (SEQ ID NO: 1209)	(SEQ ID NO: 297)
  ASYRCPDYKCSHTKH	NTLSGRSENHSG
  (SEQ ID NO: 1210)	(SEQ ID NO: 298)
  LPRCPDHPIKCIETK	NTLSGRSGNHGS
  (SEQ ID NO: 1211)	(SEQ ID NO: 299)
  YTFGCPDRYCDRAAT	TSTSGRSANPRG
  (SEQ ID NO: 1212)	(SEQ ID NO: 300)
  RGCPDFNPPSHCYTA	TSGRSANP
  (SEQ ID NO: 1213)	(SEQ ID NO: 301)
  RDYCGPQSPDYCHEI	VHMPLGFLGP
  (SEQ ID NO: 1214)	(SEQ ID NO: 302)
  PNKPCPDLQCYVTNY	AVGLLAPP
  (SEQ ID NO: 1215)	(SEQ ID NO: 303)
  PRVACGEPDLCYSNT	AQNLLGMV
  (SEQ ID NO: 1216)	(SEQ ID NO: 304)
  RGCKKHTISTLTCPD	QNQALRMA
  (SEQ ID NO: 1217)	(SEQ ID NO: 305)
  PAYRCPDRPPCKNQM	LAAPLGLL
  (SEQ ID NO: 1218)	(SEQ ID NO: 306)
  NARCYPYFGDNCHMN	STFPFGMF
  (SEQ ID NO: 1220)	(SEQ ID NO: 307)
  PTLRCPDRWCYDSPR	ISSGLLSS
  (SEQ ID NO: 1221)	(SEQ ID NO: 308)
  PSNLCPDKWCQTWRS	PAGLWLDP
  (SEQ ID NO: 1222)	(SEQ ID NO: 309)
  TPRYCAASYCPAHGY	VAGRSMRP
  (SEQ ID NO: 1223)	(SEQ ID NO: 310)
  RPGCGAVSPRCPDAP	VVPEGRRS
  (SEQ ID NO: 1224)	(SEQ ID NO: 311)
  VLRCHKQNPDNCNNH	ILPRSPAF
  (SEQ ID NO: 1225)	(SEQ ID NO: 312)
  GVKSCREPDFCSRGS	MVLGRSLL
  (SEQ ID NO: 1226)	(SEQ ID NO: 313)
  RNNLCPDYSCNNHNS	QGRAITFI
  (SEQ ID NO: 1227)	(SEQ ID NO: 314)
  RAACHRLNPDACTNG	SPRSIMLA
  (SEQ ID NO: 1228)	(SEQ ID NO: 315)
  VCQSDRIPDYVICTD	SMLRSMPL
  (SEQ ID NO: 1229)	(SEQ ID NO: 316)
  RNCRIASINPDYCNI	SARGPSRW
  (SEQ ID NO: 1230)	(SEQ ID NO: 319)
  KEWRCPDYKCKPSYH	GWHTGRN
  (SEQ ID NO: 1231)	(SEQ ID NO: 320)
  NLRICHKSLCPDYIK	HTGRSGAL
  (SEQ ID NO: 1232)	(SEQ ID NO: 321)
  NTHKCSNTNICPSFN	AARGPAIH
  (SEQ ID NO: 1233)	(SEQ ID NO: 322)
  STRYCQASQCQMSPY	RGPAFNPM
  (SEQ ID NO: 1234)	(SEQ ID NO: 323)
  THRFCTASLCNKNTS	SSRGPAYL
  (SEQ ID NO: 1235)	(SEQ ID NO: 324)
  YTLCNTRSPDWCPNK	RGPATPIM
  (SEQ ID NO: 1236)	(SEQ ID NO: 325)
  IRCTTGQSPDYCPQS	RGPA
  (SEQ ID NO: 1237)	(SEQ ID NO: 326)
  RCNQPDKNDQMLCNI	GGQPSGMWGW
  (SEQ ID NO: 1238)	(SEQ ID NO: 327)
  GTCRTDHQSPDYCYY	FPRPLGITGL
  (SEQ ID NO: 1239)	(SEQ ID NO: 328)
  RGCFRSGDSLGMCPD	SPLTGRSG
  (SEQ ID NO: 1240)	(SEQ ID NO: 329)
  SGCFDSNEHRHCSRI	SAGFSLPA
  (SEQ ID NO: 1241)	(SEQ ID NO: 330)
  NRCMKLWYNPDCVAR	LAPLGLQRR
  (SEQ ID NO: 1242)	(SEQ ID NO: 331)
  PLCARPHYWSPCDQS	SGGPLGVR
  (SEQ ID NO: 1243)	(SEQ ID NO: 332)
  DSKCHPNSPDYCFNS	PLGL
  (SEQ ID NO: 1244)	(SEQ ID NO: 333)
  NGSCRPLGGDFCGNR	ISSGLSS
  (SEQ ID NO: 1245)	(SEQ ID NO: 334)
  KTRCIEMSGDYCAKS	PVGYTSSL
  (SEQ ID NO: 1246)	(SEQ ID NO: 335)
  IRPCMYNWGDLCNQF	DWLYWPGI
  (SEQ ID NO: 1247)	(SEQ ID NO: 336)
  VKTCMENNPDYCYNN	LKAAPRWA
  (SEQ ID NO: 1248)	(SEQ ID NO: 337)
  LRMCFEASGDYCDQQ	GPSHLVLT
  (SEQ ID NO: 1249)	(SEQ ID NO: 338)
  IRKCQLDGPDQCMLT	LPGGLSPW
  (SEQ ID NO: 1250)	(SEQ ID NO: 339)
  KWKCHKNNPNYCNNR	MGLFSEAG
  (SEQ ID NO: 1251)	(SEQ ID NO: 340)
  RTMCLDTNPDYCQSH	SPLPLRVP
  (SEQ ID NO: 1252)	(SEQ ID NO: 341)
  LAACHSMDSHRCPDY	RMHLRSLG
  (SEQ ID NO: 1253)	(SEQ ID NO: 342)
  RSPCIHNATMCPDYT	LLAPSHRA
  (SEQ ID NO: 1254)	(SEQ ID NO: 343)
  MPRCPDWPPRCSMVI	GPRSFGL
  (SEQ ID NO: 1255)	(SEQ ID NO: 344)
  VRQLCRLPDYCPSGK	GPRSFG
  (SEQ ID NO: 1256)	(SEQ ID NO: 345)
  PRPPCAQSLNCPDRA	LSGRSGNH
  (SEQ ID NO: 1257)	(SEQ ID NO: 1157)
  SFGRCTLVRTCPDFM	SGRSANPRG
  (SEQ ID NO: 1258)	(SEQ ID NO: 1158)
  RDKPCPDFSCATIHY	LSGRSDDH
  (SEQ ID NO: 1259)	(SEQ ID NO: 1161)
  ATKPCPDRWCTMSTL	LSGRSDIH
  (SEQ ID NO: 1260)	(SEQ ID NO: 1162)
  SSNRCPDLRCTHHNM	LSGRSDQH
  (SEQ ID NO: 1261)	(SEQ ID NO: 1165)
  RGSMCPDLHCSLSHI	LSGRSDTH
  (SEQ ID NO: 1262)	(SEQ ID NO: 1166)
  NYQRCPDRTCMHNII	LSGRSDYH
  (SEQ ID NO: 1263)	(SEQ ID NO: 1169)
  QKRPCPDRKCHAHYN	LSGRSDNP
  (SEQ ID NO: 1264)	(SEQ ID NO: 1520)
  QNHRCPDRWCNKTTN	LSGRSANP
  (SEQ ID NO: 1265)	(SEQ ID NO: 1695)
  RLNLCPDKHCHMTNL	LSGRSANI
  (SEQ ID NO: 1266)	(SEQ ID NO: 1696)
  PQDRCPDKRCTNPGN	LSGRSDNI
  (SEQ ID NO: 1267)	(SEQ ID NO: 1697)
  SRWRCPDYKCEHGKY	MIAPVAYR
  (SEQ ID NO: 1268)	(SEQ ID NO: 1698)
  YENQCPDLYCNRYSM	RPSPMWAY
  (SEQ ID NO: 1269)	(SEQ ID NO: 1699)
  TARSCPVFNCPDNNS	WATPRPMR
  (SEQ ID NO: 1270)	(SEQ ID NO: 1700)
  MDQRCPDAWCTSKPK	FRLLDWQW
  (SEQ ID NO: 1271)	(SEQ ID NO: 1701)
  GDLRCPDRLCPRHSL	ISSGL
  (SEQ ID NO: 1272)	(SEQ ID NO: 1702)
  IQYLCPDYHCKASNN	ISSGLLS
  (SEQ ID NO: 1273)	(SEQ ID NO: 1703)
  QHHRCPDRYCNSNNN	ISSGLL
  (SEQ ID NO: 1274)	(SEQ ID NO: 1704)
  TVALCPDYSCYHINN	ISSGLLSGRSDNH
  (SEQ ID NO: 1275)	(SEQ ID NO: 214)
  SPWRCPDRYCLSNHD	AVGLLAPPGGLSGRSDNH
  (SEQ ID NO: 1276)	(SEQ ID NO: 318)
  SSKRCPDRFCNKTHA	ISSGLLSSGGSGGSLSGRSDNH
  (SEQ ID NO: 1277)	(SEQ ID NO: 346)
  HTDRCPDYKCSQNHF	ISSGLLSSGGSGGSLSGRSDNH
  (SEQ ID NO: 1278)	(SEQ ID NO: 346)
  SRSNCTPQRCNSDYH	AVGLLAPPGGTSTSGRSANPRG
  (SEQ ID NO: 1279)	(SEQ ID NO: 347)
  FAARCPDKYCAIHTN	TSTSGRSANPRGGGAVGLLAPP
  (SEQ ID NO: 1280)	(SEQ ID NO: 348)
  GSARCPDLVCQQTKQ	VHMPLGFLGPGGTSTSGRSANPRG
  (SEQ ID NO: 1281)	(SEQ ID NO: 349)
  RNLMCPDKFCNKNTK	TSTSGRSANPRGGGVHMPLGFLGP
  (SEQ ID NO: 1282)	(SEQ ID NO: 350)
  NIRLCPDKVCTPTWV	LSGRSDNHGGAVGLLAPP
  (SEQ ID NO: 1283)	(SEQ ID NO: 351)
  MTDLCPDAHCAKTHM	VHMPLGFLGPGGLSGRSDNH
  (SEQ ID NO: 1284)	(SEQ ID NO: 352)
  PYSRLCAYPCPDFVG	LSGRSDNHGGVHMPLGFLGP
  (SEQ ID NO: 1285)	(SEQ ID NO: 353)
  LCGCARSPDYCKCRG	LSGRSDNHGGSGGSISSGLLSS
  (SEQ ID NO: 1286)	(SEQ ID NO: 354)
  WGRCERVPDCCCPRG	LSGRSGNHGGSGGSISSGLLSS
  (SEQ ID NO: 1287)	(SEQ ID NO: 355)
  TRNTCHTRICYGMAC	ISSGLLSSGGSGGSLSGRSGNH
  (SEQ ID NO: 1288)	(SEQ ID NO: 356)
  CVCTSCSSYWTLCPD	LSGRSDNHGGSGGSQNQALRMA
  (SEQ ID NO: 1289)	(SEQ ID NO: 357)
  LCCSRGSNCPDRCTW	QNQALRMAGGSGGSLSGRSDNH
  (SEQ ID NO: 1290)	(SEQ ID NO: 358)
  CCPLCQANMCPDNQS	LSGRSGNHGGSGGSQNQALRMA
  (SEQ ID NO: 1291)	(SEQ ID NO: 359)
  ECKLCCPDLYCGGTM	QNQALRMAGGSGGSLSGRSGNH
  (SEQ ID NO: 1292)	(SEQ ID NO: 360)
  CSNPMCAYCCPDLIL	ISSGLLSGRSGNH
  (SEQ ID NO: 1293)	(SEQ ID NO: 361)
  CPRCNTYSKHDCYHQ	ISSGLLSSGGSGGSLSGRNH
  (SEQ ID NO: 1294)	(SEQ ID NO: 1091)
  FCCASKMPAPSNCHT	ISSGLLSGRSANPRG
  (SEQ ID NO: 1295)	(SEQ ID NO: 1092)
  	AVGLLAPPTSGRSANPRG
  	(SEQ ID NO: 1093)
  	AVGLLAPPSGRSANPRG
  	(SEQ ID NO: 1094)
  	ISSGLLSGRSDDH
  	(SEQ ID NO: 1095)
  	ISSGLLSGRSDIH
  	(SEQ ID NO: 1096)
  	ISSGLLSGRSDQH
  	(SEQ ID NO: 1097)
  	ISSGLLSGRSDTH
  	(SEQ ID NO: 1098)
  	ISSGLLSGRSDYH
  	(SEQ ID NO: 1099)
  	ISSGLLSGRSDNP
  	(SEQ ID NO: 1100)
  	ISSGLLSGRSANP
  	(SEQ ID NO: 1101)
  	ISSGLLSGRSANI
  	(SEQ ID NO: 1102)
  	AVGLLAPPGGLSGRSDDH
  	(SEQ ID NO: 1103)
  	AVGLLAPPGGLSGRSDIH
  	(SEQ ID NO: 1104)
  	AVGLLAPPGGLSGRSDQH
  	(SEQ ID NO: 1105)
  	AVGLLAPPGGLSGRSDTH
  	(SEQ ID NO: 1106)
  	AVGLLAPPGGLSGRSDYH
  	(SEQ ID NO: 1107)
  	AVGLLAPPGGLSGRSDNP
  	(SEQ ID NO: 1108)
  	AVGLLAPPGGLSGRSANP
  	(SEQ ID NO: 1109)
  	AVGLLAPPGGLSGRSANI
  	(SEQ ID NO: 1110)
  	ISSGLLSGRSDNI
  	(SEQ ID NO: 1111)
  	AVGLLAPPGGLSGRSDNI
  	(SEQ ID NO: 1112)

• TABLE 13C
  	VL	VH	VL CDRs	VH CDRs
  	SEQ	SEQ	SEQ ID NO:	SEQ ID NO:

  Mask Sequence	Substrates:	ID NO:	ID NO:	CDR1	CDR2	CDR3	CDR1	CDR2	CDR3

  GCDFTSAKHNCGSGW	LSGRSDNH	638	1514	VL CDRs of SEQ ID	VH CDRs of SEQ ID
  (SEQ ID NO: 1351)	(SEQ ID NO: 294)			NO: 638	NO: 1514

  VGSNCWTGPACALTS	TGRGPSWV			1711	1712	1713	1714	1715	1716
  (SEQ ID NO: 1352)	(SEQ ID NO: 295)
  FCAVMFDFLSDRCLH	PLTGRSGG
  (SEQ ID NO: 1353)	(SEQ ID NO: 296)
  FCPPWLDYLGNKCMT	TARGPSFK
  (SEQ ID NO: 1354)	(SEQ ID NO: 297)
  MSCWDFSSAQGCGQH	NTLSGRSENHSG
  (SEQ ID NO: 1355)	(SEQ ID NO: 298)
  LMCADLHYNHYNCKY	NTLSGRSGNHGS
  (SEQ ID NO: 1356)	(SEQ ID NO: 299)
  ELCGWQSFSGVCTSE	TSTSGRSANPRG
  (SEQ ID NO: 1357)	(SEQ ID NO: 300)
  WTYENCWASCQPHLE	TSGRSANP
  (SEQ ID NO: 1358)	(SEQ ID NO: 301)
  KLTEDFSSAA (SEQ	VHMPLGFLGP
  ID NO: 1359)	(SEQ ID NO: 302)
  VGQSCFSGLVCDRQL	AVGLLAPP
  (SEQ ID NO: 1360)	(SEQ ID NO: 303)
  ISHYCFSGKSCRD	AQNLLGMV
  (SEQ ID NO: 1361)	(SEQ ID NO: 304)
  HCIPDFTSAAGDCMR	QNQALRMA
  (SEQ ID NO: 1362)	(SEQ ID NO: 305)
  RLVSAYSFS (SEQ ID	LAAPLGLL
  NO: 1363)	(SEQ ID NO: 306)
  KFHHSHPLVHDFTSA	STFPFGMF
  (SEQ ID NO: 1364)	(SEQ ID NO: 307)
  ASYPDFSSANGVGLR	ISSGLLSS
  (SEQ ID NO: 1365)	(SEQ ID NO: 308)
  GLATTLSNVDFTSAG	PAGLWLDP
  (SEQ ID NO: 1366)	(SEQ ID NO: 309)
  DFTSANSAFSGDAST	VAGRSMRP
  (SEQ ID NO: 1367)	(SEQ ID NO: 310)
  GRLPGHSVVDFTSAW	VVPEGRRS
  (SEQ ID NO: 1368)	(SEQ ID NO: 311)
  SGSFYSSSAFDFTSA	ILPRSPAF
  (SEQ ID NO: 1369)	(SEQ ID NO: 312)
  CDDFTSAQHSRINEC	MVLGRSLL
  (SEQ ID NO: 1370)	(SEQ ID NO: 313)
  CDFTSAQGKKCRTAL	QGRAITFI
  (SEQ ID NO: 1371)	(SEQ ID NO: 314)
  YYIDKYQSPSYGPVL	SPRSIMLA
  (SEQ ID NO: 1372)	(SEQ ID NO: 315)
  FSVARARSSADFTSS	SMLRSMPL
  (SEQ ID NO: 1373)	(SEQ ID NO: 316)
  DSDFTSAGSADSRSR	SARGPSRW
  (SEQ ID NO: 1374)	(SEQ ID NO: 319)
  CDFTSATSISKRCDH	GWHTGRN
  (SEQ ID NO: 1375)	(SEQ ID NO: 320)
  IESSASSWGLQASRN	HTGRSGAL
  (SEQ ID NO: 1376)	(SEQ ID NO: 321)
  PRYHNLNFTTPALSPGS	AARGPAIH
  (SEQ ID NO: 1377)	(SEQ ID NO: 322)
  DLFARFPLDRDFTSA	RGPAFNPM
  (SEQ ID NO: 1378)	(SEQ ID NO: 323)
  HCNFTTPPYCSSTLW	SSRGPAYL
  (SEQ ID NO: 1379)	(SEQ ID NO: 324)
  NVPIILLTDRQLLSG	RGPATPIM
  (SEQ ID NO: 1380)	(SEQ ID NO: 325)
  NPTACDFTSSMATYC	RGPA
  (SEQ ID NO: 1381)	(SEQ ID NO: 326)
  FVRTVRFSNSMFSVP	GGQPSGMWGW
  (SEQ ID NO: 1382)	(SEQ ID NO: 327)
  YDFSSASNSSPSRQT	FPRPLGITGL
  (SEQ ID NO: 1383)	(SEQ ID NO: 328)
  AHPDFSSAMRGNLLG	SPLTGRSG
  (SEQ ID NO: 1384)	(SEQ ID NO: 329)
  SSHVVHKDFTSANSR	SAGFSLPA
  (SEQ ID NO: 1385)	(SEQ ID NO: 330)
  CPDFTSANGGGCWQM	LAPLGLQRR
  (SEQ ID NO: 1386)	(SEQ ID NO: 331)
  SLGQSYPTDFTCPGC	SGGPLGVR
  (SEQ ID NO: 1387)	(SEQ ID NO: 332)
  ASMRSHEQRDFTSAY	PLGL
  (SEQ ID NO: 1388)	(SEQ ID NO: 333)
  SCQFWFTLCSGGVFH	ISSGLSS
  (SEQ ID NO: 1389)	(SEQ ID NO: 334)
  PYPNNRTGMHDFTSA	PVGYTSSL
  (SEQ ID NO: 1390)	(SEQ ID NO: 335)
  KPFPIDFTSAGTSGT	DWLYWPGI
  (SEQ ID NO: 1391)	(SEQ ID NO: 336)
  SIKSFIPRDDFTSAA	LKAAPRWA
  (SEQ ID NO: 1392)	(SEQ ID NO: 337)
  GIKNPATPFVDFTSA	GPSHLVLT
  (SEQ ID NO: 1393)	(SEQ ID NO: 338)
  LSHTYPRGSSTIEAS	LPGGLSPW
  (SEQ ID NO: 1394)	(SEQ ID NO: 339)
  PSLDFSSAT (SEQ ID	MGLFSEAG
  NO: 1395)	(SEQ ID NO: 340)
  AFTPRIAPTFDVMKE	SPLPLRVP
  (SEQ ID NO: 1396)	(SEQ ID NO: 341)
  LCGLQIPPDCERS	RMHLRSLG
  (SEQ ID NO: 1397)	(SEQ ID NO: 342)
  AAKMVSHSERDFTSA	LLAPSHRA
  (SEQ ID NO: 1398)	(SEQ ID NO: 343)
  VSVECFSGMQCPHYY	GPRSFGL
  (SEQ ID NO: 1399)	(SEQ ID NO: 344)
  ASKCRLPCMASTQIY	GPRSFG
  (SEQ ID NO: 1400)	(SEQ ID NO: 345)
  GLRSCNIYFSIPCTY	LSGRSGNH
  (SEQ ID NO: 1401)	(SEQ ID NO: 1157)
  RGTSDGTLDFTTARS	SGRSANPRG
  (SEQ ID NO: 1402)	(SEQ ID NO: 1158)
  SMYPSASRLLHPQYP	LSGRSDDH
  (SEQ ID NO: 1403)	(SEQ ID NO: 1161)
  HCISCYDFTSAAGSF	LSGRSDIH
  (SEQ ID NO: 1404)	(SEQ ID NO: 1162)
  SSGRWGDAWACARIC	LSGRSDQH
  (SEQ ID NO: 1405)	(SEQ ID NO: 1165)
  RVFSDFTSASHSFGG	LSGRSDTH
  (SEQ ID NO: 1406)	(SEQ ID NO: 1166)
  TDRHSASGRDFTSAH	LSGRSDYH
  (SEQ ID NO: 1407)	(SEQ ID NO: 1169)
  AHCEDFSSAERIATMGC	LSGRSDNP
  (SEQ ID NO: 1408)	(SEQ ID NO: 1520)
  ACDPYSFSIPCDDRL	LSGRSANP
  (SEQ ID NO: 1409)	(SEQ ID NO: 1695)
  NSPFTLSHIYDR (SEQ	LSGRSANI
  ID NO: 1410)	(SEQ ID NO: 1696)
  IGINFTTPSAFVAFP	LSGRSDNI
  (SEQ ID NO: 1411)	(SEQ ID NO: 1697)
  RDAFPIYRNADFSTP	MIAPVAYR
  (SEQ ID NO: 1412)	(SEQ ID NO: 1698)
  SIPNASSYNFTSSSG	RPSPMWAY
  (SEQ ID NO: 1413)	(SEQ ID NO: 1699)
  AGIPDKRHTYDFTSA	WATPRPMR
  (SEQ ID NO: 1414)	(SEQ ID NO: 1700)
  WPLAHDSRDWNFTTP	FRLLDWQW
  (SEQ ID NO: 1415)	(SEQ ID NO: 1701)
  RHSPSSGHVDFTSAG	ISSGL
  (SEQ ID NO: 1416)	(SEQ ID NO: 1702)
  SCFAWTDPVWNRCSW	ISSGLLS
  (SEQ ID NO: 1417)	(SEQ ID NO: 1703)
  MPCDWTGPGKIWCGG	ISSGLL
  (SEQ ID NO: 1418)	(SEQ ID NO: 1704)
  RDCDFSTANFRSCNK	ISSGLLSGRSDNH
  (SEQ ID NO: 1419)	(SEQ ID NO: 214)
  LSCVVSPNYLHCNDH	AVGLLAPPGGLSGRSDNH
  (SEQ ID NO: 1420)	(SEQ ID NO: 318)
  FVCGLYSFSGVCQGV	ISSGLLSSGGSGGSLSGRSDNH
  (SEQ ID NO: 1421)	(SEQ ID NO: 346)
  IGLMCFSGLQCPMLA	ISSGLLSSGGSGGSLSGRSDNH
  (SEQ ID NO: 1422)	(SEQ ID NO: 346)
  PGMNCFSGEICQMST	AVGLLAPPGGTSTSGRSANPRG
  (SEQ ID NO: 1423)	(SEQ ID NO: 347)
  GDVGSCWASCGLQGG	TSTSGRSANPRGGGAVGLLAPP
  (SEQ ID NO: 1424)	(SEQ ID NO: 348)
  SQFQDCWASCGASFT	VHMPLGFLGPGGTSTSGRSANPRG
  (SEQ ID NO: 1425)	(SEQ ID NO: 349)
  VGSLNCWYSCGDIWL	TSTSGRSANPRGGGVHMPLGFLGP
  (SEQ ID NO: 1426)	(SEQ ID NO: 350)
  MCESWLNFLGDQCGM	LSGRSDNHGGAVGLLAPP
  (SEQ ID NO: 1427)	(SEQ ID NO: 351)
  RCMISQSSFSGMCGM	VHMPLGFLGPGGLSGRSDNH
  (SEQ ID NO: 1428)	(SEQ ID NO: 352)
  NCAPWTSNMSNHCLK	LSGRSDNHGGVHMPLGFLGP
  (SEQ ID NO: 1429)	(SEQ ID NO: 353)
  LCGVGSATGLELCGV	LSGRSDNHGGSGGSISSGLLSS
  (SEQ ID NO: 1430)	(SEQ ID NO: 354)
  GCDFSSLGGRQPCTP	LSGRSGNHGGSGGSISSGLLSS
  (SEQ ID NO: 1431)	(SEQ ID NO: 355)
  MGCNFTTYPYHTCNT	ISSGLLSSGGSGGSLSGRSGNH
  (SEQ ID NO: 1432)	(SEQ ID NO: 356)
  GSCDFTSGAGKKCGS	LSGRSDNHGGSGGSQNQALRMA
  (SEQ ID NO: 1433)	(SEQ ID NO: 357)
  VSCDFTSSHARMCSR	QNQALRMAGGSGGSLSGRSDNH
  (SEQ ID NO: 1434)	(SEQ ID NO: 358)
  MRCIDFYYNHINCIG	LSGRSGNHGGSGGSQNQALRMA
  (SEQ ID NO: 1435)	(SEQ ID NO: 359)
  RSCDFTSAANKYCAT	QNQALRMAGGSGGSLSGRSGNH
  (SEQ ID NO: 1436)	(SEQ ID NO: 360)
  LYCDSFSVPRPNCAP	ISSGLLSGRSGNH
  (SEQ ID NO: 1437)	(SEQ ID NO: 361)
  NSCDFTSARVSKCST	ISSGLLSSGGSGGSLSGRNH
  (SEQ ID NO: 1438)	(SEQ ID NO: 1091)
  STCSDNFTTPMPCNT	ISSGLLSGRSANPRG
  (SEQ ID NO: 1439)	(SEQ ID NO: 1092)
  DICNDRPNLTHCHYF	AVGLLAPPTSGRSANPRG
  (SEQ ID NO: 1440)	(SEQ ID NO: 1093)
  LRCDDFTSAIGCRGY	AVGLLAPPSGRSANPRG
  (SEQ ID NO: 1441)	(SEQ ID NO: 1094)
  EGCDFTSALHSCNNY	ISSGLLSGRSDDH
  (SEQ ID NO: 1442)	(SEQ ID NO: 1095)
  RKGCGDFTSASCFVV	ISSGLLSGRSDIH
  (SEQ ID NO: 1443)	(SEQ ID NO: 1096)
  GMLCAGSSFGLCESM	ISSGLLSGRSDQH
  (SEQ ID NO: 1444)	(SEQ ID NO: 1097)
  RESCFGSSLGLCTNK	ISSGLLSGRSDTH
  (SEQ ID NO: 1445)	(SEQ ID NO: 1098)
  ILRCYDIPTNCMNFN	ISSGLLSGRSDYH
  (SEQ ID NO: 1446)	(SEQ ID NO: 1099)
  NSECTFGAMYCRNKP	ISSGLLSGRSDNP
  (SEQ ID NO: 1447)	(SEQ ID NO: 1100)
  ASGCFDEDIRCSGGA	ISSGLLSGRSANP
  (SEQ ID NO: 1448)	(SEQ ID NO: 1101)
  HYFCNQSNPSCQTAP	ISSGLLSGRSANI
  (SEQ ID NO: 1449)	(SEQ ID NO: 1102)
  AMGCELGGAGCIGSP	AVGLLAPPGGLSGRSDDH
  (SEQ ID NO: 1450)	(SEQ ID NO: 1103)
  TLKCHMPRKLCANDP	AVGLLAPPGGLSGRSDIH
  (SEQ ID NO: 1451)	(SEQ ID NO: 1104)
  RPACRDLPHNCITST	AVGLLAPPGGLSGRSDQH
  (SEQ ID NO: 1452)	(SEQ ID NO: 1105)
  QMSCHGNFTTCHSNP	AVGLLAPPGGLSGRSDTH
  (SEQ ID NO: 1453)	(SEQ ID NO: 1106)
  LTGCARGARPCRLRV	AVGLLAPPGGLSGRSDYH
  (SEQ ID NO: 1454)	(SEQ ID NO: 1107)
  WSELCLAGPSCGWVG	AVGLLAPPGGLSGRSDNP
  (SEQ ID NO: 1455)	(SEQ ID NO: 1108)
  VTKSCWQLPHCITAP	AVGLLAPPGGLSGRSANP
  (SEQ ID NO: 1456)	(SEQ ID NO: 1109)
  KAASCPHNQICNMTA	AVGLLAPPGGLSGRSANI
  (SEQ ID NO: 1457)	(SEQ ID NO: 1110)
  VSKNCFSGMMCPVFA	ISSGLLSGRSDNI
  (SEQ ID NO: 1458)	(SEQ ID NO: 1111)
  NRSSCWTGPTCHVLH	AVGLLAPPGGLSGRSDNI
  (SEQ ID NO: 1459)	(SEQ ID NO: 1112)
  ARTGCSGPVCLNDVS
  (SEQ ID NO: 1460)
  STRTCLAFTCINGNT
  (SEQ ID NO: 1461)
  MLDGNCWYACSYKNT
  (SEQ ID NO: 1462)
  FSRSDCWSACAPWRV
  (SEQ ID NO: 1463)
  GGRMDCWASCQPLSR
  (SEQ ID NO: 1464)
  NSPHSCMTNCDFTSA
  (SEQ ID NO: 1465)

• TABLE 13D
  			LC CDRs	HC CDRs
  	LC	HC	SEQ ID NO:	SEQ ID NO:

  Mask Sequence	Substrates:	SEQ ID NO:	SEQ ID NO:	CDR1	CDR2	CDR3	CDR1	CDR2	CDR3

  DYTYCRWVNWCLSGV	LSGRSDNH	543	546	LC CDRs of	HC CDRs of
  (SEQ ID NO: 384)	(SEQ ID NO: 294)			SEQ ID NO: 543	SEQ ID NO: 546
  ILCPEDPWGHKCKLP	TGRGPSWV
  (SEQ ID NO: 385)	(SEQ ID NO: 295)
  TNIWSCQTYCDHKHK	PLTGRSGG
  (SEQ ID NO: 386)	(SEQ ID NO: 296)
  SDHKCKLQNCMNTKV	TARGPSFK
  (SEQ ID NO: 387)	(SEQ ID NO: 297)
  PGNCHPMQKEMCQFI	NTLSGRSENHSG
  (SEQ ID NO: 388)	(SEQ ID NO: 298)
  VEHLCYTHNKCKHPD	NTLSGRSGNHGS
  (SEQ ID NO: 389)	(SEQ ID NO: 299)
  TIPRCGQHPKCKDTL	TSTSGRSANPRG
  (SEQ ID NO: 390)	(SEQ ID NO: 300)
  ACRICQDHPKTKWNS	TSGRSANP
  (SEQ ID NO: 391)	(SEQ ID NO: 301)
  LIQCTGNLDHKCKHY	VHMPLGFLGP
  (SEQ ID NO: 392)	(SEQ ID NO: 302)
  IPCHHSADHKHKCTS	AVGLLAPP
  (SEQ ID NO: 393)	(SEQ ID NO: 303)
  SRQICADYNCHNKYK	AQNLLGMV
  (SEQ ID NO: 394)	(SEQ ID NO: 304)
  QPCNPQIDHKIKCIY	QNQALRMA
  (SEQ ID NO: 395)	(SEQ ID NO: 305)
  HYTICMTHNKCKDMA	LAAPLGLL
  (SEQ ID NO: 396)	(SEQ ID NO: 306)
  ANSCLAVEHKCKHNY	STFPFGMF
  (SEQ ID NO: 397)	(SEQ ID NO: 307)
  AALHCTEHKCKNHIK	ISSGLLSS
  (SEQ ID NO: 398)	(SEQ ID NO: 308)
  APCIINTVDWKSCEI	PAGLWLDP
  (SEQ ID NO: 399)	(SEQ ID NO: 309)
  ATNWCTHKQKCKQDM	VAGRSMRP
  (SEQ ID NO: 400)	(SEQ ID NO: 310)
  DCYNEHKLKTRVCNN	VVPEGRRS
  (SEQ ID NO: 401)	(SEQ ID NO: 311)
  DEMQCSHKQKCTNSK	ILPRSPAF
  (SEQ ID NO: 402)	(SEQ ID NO: 312)
  DVGICSQHNKCKPTK	MVLGRSLL
  (SEQ ID NO: 403)	(SEQ ID NO: 313)
  EKYCSSDDHKCKITL	QGRAITFI
  (SEQ ID NO: 404)	(SEQ ID NO: 314)
  ELECSHNKVKNCIQI	SPRSIMLA
  (SEQ ID NO: 405)	(SEQ ID NO: 315)
  ELHPCNTHKCKPIVN	SMLRSMPL
  (SEQ ID NO: 406)	(SEQ ID NO: 316)
  EVGSCNHPKCKSNNY	SARGPSRW
  (SEQ ID NO: 407)	(SEQ ID NO: 319)
  EYSPSLAHPKLKDNA	GWHTGRN
  (SEQ ID NO: 408)	(SEQ ID NO: 320)
  FESLHPKGKHPEDLG	HTGRSGAL
  (SEQ ID NO: 409)	(SEQ ID NO: 321)
  FPLCVRADRVCGDAQ	AARGPAIH
  (SEQ ID NO: 410)	(SEQ ID NO: 322)
  FQAPPASHNKLKPSL	RGPAFNPM
  (SEQ ID NO: 411)	(SEQ ID NO: 323)
  GAIDSCHHKCKSPHY	SSRGPAYL
  (SEQ ID NO: 412)	(SEQ ID NO: 324)
  GKIYTCEHNCTFGYS	RGPATPIM
  (SEQ ID NO: 413)	(SEQ ID NO: 325)
  HCTVNNHSSDHKCKI	RGPA
  (SEQ ID NO: 414)	(SEQ ID NO: 326)
  HGTQCTHNKCKPILS	GGQPSGMWGW
  (SEQ ID NO: 415)	(SEQ ID NO: 327)
  HIGWCLHPKCKTTTT	FPRPLGITGL
  (SEQ ID NO: 416)	(SEQ ID NO: 328)
  HLRTCIQKWCEHKMK	SPLTGRSG
  (SEQ ID NO: 417)	(SEQ ID NO: 329)
  HTDCTMMSNHKCKIN	SAGFSLPA
  (SEQ ID NO: 418)	(SEQ ID NO: 330)
  IRQQCTALACLLKVH	LAPLGLQRR
  (SEQ ID NO: 419)	(SEQ ID NO: 331)
  KGCSTHKMRAYCNQM	SGGPLGVR
  (SEQ ID NO: 420)	(SEQ ID NO: 332)
  KMFTPCKIWCNNSYN	PLGL
  (SEQ ID NO: 421)	(SEQ ID NO: 333)
  KTMCSGHKQKCNNSS	ISSGLSS
  (SEQ ID NO: 422)	(SEQ ID NO: 334)
  LACHSASLVDHKCKL	PVGYTSSL
  (SEQ ID NO: 423)	(SEQ ID NO: 335)
  LCNVSMDHKHKPCYL	DWLYWPGI
  (SEQ ID NO: 424)	(SEQ ID NO: 336)
  LGLNCFSEHKCKEHM	LKAAPRWA
  (SEQ ID NO: 425)	(SEQ ID NO: 337)
  LGTCTHKHKNCNYTL	GPSHLVLT
  (SEQ ID NO: 426)	(SEQ ID NO: 338)
  LHEGCTTHNKCKPIA	LPGGLSPW
  (SEQ ID NO: 427)	(SEQ ID NO: 339)
  LKRSCTGHWTCYTNW	MGLFSEAG
  (SEQ ID NO: 428)	(SEQ ID NO: 340)
  LQRCTHKEKYCHAIH	SPLPLRVP
  (SEQ ID NO: 429)	(SEQ ID NO: 341)
  LSHCYDHKRKCSYIV	RMHLRSLG
  (SEQ ID NO: 430)	(SEQ ID NO: 342)
  LSKCHNKEKNCSNNN	LLAPSHRA
  (SEQ ID NO: 431)	(SEQ ID NO: 343)
  MDTCEMHKQKCRPSF	GPRSFGL
  (SEQ ID NO: 432)	(SEQ ID NO: 344)
  MHNECLTHKCKVPIT	GPRSFG
  (SEQ ID NO: 433)	(SEQ ID NO: 345)
  MLTLCNTNACHKEKN	LSGRSGNH
  (SEQ ID NO: 434)	(SEQ ID NO: 1157)
  MRPCLNNLEHKCKHY	SGRSANPRG
  (SEQ ID NO: 435)	(SEQ ID NO: 1158)
  MSRCPTHKMKCSLNI	LSGRSDDH
  (SEQ ID NO: 436)	(SEQ ID NO: 1161)
  MWICQEHKLKCMTDT	LSGRSDIH
  (SEQ ID NO: 437)	(SEQ ID NO: 1162)
  MYYCKRRSAFYCTLN	LSGRSDQH
  (SEQ ID NO: 438)	(SEQ ID NO: 1165)
  NDCQHDKQMHKCKMH	LSGRSDTH
  (SEQ ID NO: 439)	(SEQ ID NO: 1166)
  NFGPCPMLLGCFGFR	LSGRSDYH
  (SEQ ID NO: 440)	(SEQ ID NO: 1169)
  NHTDCSHPKCKSHDS	LSGRSDNP
  (SEQ ID NO: 441)	(SEQ ID NO: 1520)
  NLNCPHKQKNCDKYH	LSGRSANP
  (SEQ ID NO: 442)	(SEQ ID NO: 1695)
  NPQCTPIDHKCKTHH	LSGRSANI
  (SEQ ID NO: 443)	(SEQ ID NO: 1696)
  NTTSCTHPKCKHQGK	LSGRSDNI
  (SEQ ID NO: 444)	(SEQ ID NO: 1697)
  NVGGCDNYGCHKLKN	MIAPVAYR
  (SEQ ID NO: 445)	(SEQ ID NO: 1698)
  PCSPGNLTWDHKCKY	RPSPMWAY
  (SEQ ID NO: 446)	(SEQ ID NO: 1699)
  PFTKCHGFNKCKEHT	WATPRPMR
  (SEQ ID NO: 447)	(SEQ ID NO: 1700)
  PGDKCTHKEKCYYNN	FRLLDWQW
  (SEQ ID NO: 448)	(SEQ ID NO: 1701)
  PNICNLDHKRKCRIN	ISSGL
  (SEQ ID NO: 449)	(SEQ ID NO: 1702)
  PQLACKHPKCKDAGN	ISSGLLS
  (SEQ ID NO: 450)	(SEQ ID NO: 1703)
  PSCTMWTHGGVCKHA	ISSGLL
  (SEQ ID NO: 451)	(SEQ ID NO: 1704)
  PSHRHPLAKPGFRVE	ISSGLLSGRSDNH
  (SEQ ID NO: 452)	(SEQ ID NO: 214)
  PTCFKTHNKSKCNRV	AVGLLAPPGGLSGRSDNH
  (SEQ ID NO: 453)	(SEQ ID NO: 318)
  PTPVCHHNFHCFGYD	ISSGLLSSGGSGGSLSGRSDNH
  (SEQ ID NO: 454)	(SEQ ID NO: 346)
  QATCQWKKRSKCHNK	ISSGLLSSGGSGGSLSGRSDNH
  (SEQ ID NO: 455)	(SEQ ID NO: 346)
  QHSWCQHKAKCNYGN	AVGLLAPPGGTSTSGRSANPRG
  (SEQ ID NO: 456)	(SEQ ID NO: 347)
  QNCSPTYTTHKCKLT	TSTSGRSANPRGGGAVGLLAPP
  (SEQ ID NO: 457)	(SEQ ID NO: 348)
  QSSNCEHKRKCSSIS	VHMPLGFLGPGGTSTSGRSANPRG
  (SEQ ID NO: 458)	(SEQ ID NO: 349)
  RPCLLGLVPDHKCKL	TSTSGRSANPRGGGVHMPLGFLGP
  (SEQ ID NO: 459)	(SEQ ID NO: 350)
  RRSCMRSINTCKQKY	LSGRSDNHGGAVGLLAPP
  (SEQ ID NO: 460)	(SEQ ID NO: 351)
  RSSCPTVTPQNCENQ	VHMPLGFLGPGGLSGRSDNH
  (SEQ ID NO: 461)	(SEQ ID NO: 352)
  RTMCLDLNHKCKPSN	LSGRSDNHGGVHMPLGFLGP
  (SEQ ID NO: 462)	(SEQ ID NO: 353)
  RTYWCTNHNKCKHNM	LSGRSDNHGGSGGSISSGLLSS
  (SEQ ID NO: 463)	(SEQ ID NO: 354)
  RVENCEHNQYCHKWK	LSGRSGNHGGSGGSISSGLLSS
  (SEQ ID NO: 464)	(SEQ ID NO: 355)
  SCHEDDHKNKNICSL	ISSGLLSSGGSGGSLSGRSGNH
  (SEQ ID NO: 465)	(SEQ ID NO: 356)
  SDTCVMNHPKCKRDN	LSGRSDNHGGSGGSQNQALRMA
  (SEQ ID NO: 466)	(SEQ ID NO: 357)
  SSTCFHPNQKECMTK	QNQALRMAGGSGGSLSGRSDNH
  (SEQ ID NO: 467)	(SEQ ID NO: 358)
  SSYCGGITMRCRRAM	LSGRSGNHGGSGGSQNQALRMA
  (SEQ ID NO: 468)	(SEQ ID NO: 359)
  STGYCTYVNWCNYTN	QNQALRMAGGSGGSLSGRSGNH
  (SEQ ID NO: 469)	(SEQ ID NO: 360)
  THKCKLHLQVCTQTT	ISSGLLSGRSGNH
  (SEQ ID NO: 470)	(SEQ ID NO: 361)
  TMNCTHPKQKCQHTN	ISSGLLSSGGSGGSLSGRNH
  (SEQ ID NO: 471)	(SEQ ID NO: 1091)
  TNVLCESHNCDHKNK	ISSGLLSGRSANPRG
  (SEQ ID NO: 472)	(SEQ ID NO: 1092)
  TQHAASLGVEHKSKI	AVGLLAPPTSGRSANPRG
  (SEQ ID NO: 473)	(SEQ ID NO: 1093)
  TQLPCFDDHKCKNTN	AVGLLAPPSGRSANPRG
  (SEQ ID NO: 474)	(SEQ ID NO: 1094)
  TSDSCMRQKCEHKEK	ISSGLLSGRSDDH
  (SEQ ID NO: 475)	(SEQ ID NO: 1095)
  TTCDDHKYKHKCAQL	ISSGLLSGRSDIH
  (SEQ ID NO: 476)	(SEQ ID NO: 1096)
  TTCGAHKEKQHCIYT	ISSGLLSGRSDQH
  (SEQ ID NO: 477)	(SEQ ID NO: 1097)
  TTYCAYWHNKCKFET	ISSGLLSGRSDTH
  (SEQ ID NO: 478)	(SEQ ID NO: 1098)
  VGPTCGHAKCKQSEV	ISSGLLSGRSDYH
  (SEQ ID NO: 479)	(SEQ ID NO: 1099)
  VSHPCNTHKCKTNIV	ISSGLLSGRSDNP
  (SEQ ID NO: 480)	(SEQ ID NO: 1100)
  WDCRNTSHPKLKCHN	ISSGLLSGRSANP
  (SEQ ID NO: 481)	(SEQ ID NO: 1101)
  WSPCNSDHKRKCNNG	ISSGLLSGRSANI
  (SEQ ID NO: 482)	(SEQ ID NO: 1102)
  YANMSCEYDCHKMKY	AVGLLAPPGGLSGRSDDH
  (SEQ ID NO: 483)	(SEQ ID NO: 1103)
  YANPCTHKEKCHFKN	AVGLLAPPGGLSGRSDIH
  (SEQ ID NO: 484)	(SEQ ID NO: 1104)
  YDCSPSWTHPKCKHK	AVGLLAPPGGLSGRSDQH
  (SEQ ID NO: 485)	(SEQ ID NO: 1105)
  YGWTCTTHPKCKTTN	AVGLLAPPGGLSGRSDTH
  (SEQ ID NO: 486)	(SEQ ID NO: 1106)
  YQKCHPKAKDCGNNT	AVGLLAPPGGLSGRSDYH
  (SEQ ID NO: 487)	(SEQ ID NO: 1107)
  YWECPNMEHNKCKNN	AVGLLAPPGGLSGRSDNP
  (SEQ ID NO: 488)	(SEQ ID NO: 1108)
  PMGNRYCVLDHPKLK	AVGLLAPPGGLSGRSANP
  (SEQ ID NO: 489)	(SEQ ID NO: 1109)
  GHKSCCQKHCEYTQT	AVGLLAPPGGLSGRSANI
  (SEQ ID NO: 490)	(SEQ ID NO: 1110)
  LYLEMCSCCCWESIT	ISSGLLSGRSDNI
  (SEQ ID NO: 491)	(SEQ ID NO: 1111)
  ACQAQHCYKTYACKP	AVGLLAPPGGLSGRSDNI
  (SEQ ID NO: 492)	(SEQ ID NO: 1112)
  CCYTCSVHPKCKNQL
  (SEQ ID NO: 493)
  CKHRCSHKEKCPANH
  (SEQ ID NO: 494)
  CHVLFCLMQCCRWSL
  (SEQ ID NO: 495)
  LNSSLVFDHPKAKPN
  (SEQ ID NO: 496)
  MCLLCRSKFGCKVKG
  (SEQ ID NO: 497)
  IICNDHKCKQNQCNN
  (SEQ ID NO: 498)
  IRCSLRDSLCGCERM
  (SEQ ID NO: 499)
  TSCQPPKHKCTCNHG
  (SEQ ID NO: 500)
  TQCPHRCVKPNCWLH
  (SEQ ID NO: 501)
  KCCETKRNHKHCTYK
  (SEQ ID NO: 502)
  LPHCCHKAKHCNHTS
  (SEQ ID NO: 503)
  PAMCAAIHEKCCIKV
  (SEQ ID NO: 504)
  PRSCGNQLCPCHYYK
  (SEQ ID NO: 505)
  TNKCSCNHNMKCINY
  (SEQ ID NO: 506)
  VETCCQHNKCKYPFI
  (SEQ ID NO: 507)
  IFCCSNHEDHKCKTN
  (SEQ ID NO: 508)
  VCRLICPLTCVIGVG
  (SEQ ID NO: 509)
  FHGCCSVYSCLTNPG
  (SEQ ID NO: 510)
  ALACHPKQKPLEGQL
  (SEQ ID NO: 511)
  SIICCATSSCPLKHL
  (SEQ ID NO: 512)
  APCCRPHKEKPIDSR
  (SEQ ID NO: 513)
  WELCCPSADCRVAMG
  (SEQ ID NO: 514)
  QDHPKTKWNS (SEQ
  ID NO: 548)
  ACRICQDHPATKWNS
  (SEQ ID NO: 549)
  ACRICQDHPKTAWNS
  (SEQ ID NO: 550)
  ACRICQDAPKTKWNS
  (SEQ ID NO: 551)
  ACRICQDHAKTKWNS
  (SEQ ID NO: 552)
  DHPATKWNS
  (SEQ ID NO: 553)
  DHPKTAWNS
  (SEQ ID NO: 554)
  DAPKTKWNS
  (SEQ ID NO: 555)
  DAPATKWNS
  (SEQ ID NO: 556)
  ACRICQDHP
  (SEQ ID NO: 557)
  HPQSKDTL
  (SEQ ID NO: 558)
  HPKSQDTL
  (SEQ ID NO: 559)
  TIPRCGQHPLCLDTL
  (SEQ ID NO: 560)
  HPLSLDTL
  (SEQ ID NO: 561)
  HPASKDTL
  (SEQ ID NO: 562)
  HPKSADTL
  (SEQ ID NO: 563)
  PGNCHPLQKELCQFI
  (SEQ ID NO: 564)
  HPLQKELAQFI
  (SEQ ID NO: 565)
  HPLALELAQFI
  (SEQ ID NO: 566)
  PGNCHPLQLELCQFI
  (SEQ ID NO: 567)
  TNIWSCQTYCDHAHA
  (SEQ ID NO: 568)
  TNIWSCQTYCDHAHL
  (SEQ ID NO: 569)
  TNIWSCQTYCDHLHA
  (SEQ ID NO: 570)
  TNIWSCQTYCDHKHA
  (SEQ ID NO: 571)

• Any of the combinations described in Tables 13A, 13B, 13C, and/or 13D can be combined with human immunoglobulin constant regions to result in fully humanized IgGs including IgG1, IgG2, IgG4 or mutated constant regions to result in human IgGs with altered functions such as IgG1 N297A, IgG1 N297Q, or IgG4 S228P. Additional examples are known to those skilled in the art. Examples of Ig heavy chain constant region amino acids in which mutations in at least one amino acid leads to reduced Fc function include, but are not limited to, mutations in amino acid 228, 233, 234, 235, 236, 237, 239, 252, 254, 256, 265, 270, 297, 318, 320, 322, 327, 329, 330, and 331 of the heavy constant region. Examples of combinations of mutated amino acids are also known in the art, such as, but not limited to a combination of mutations in amino acids 234, 235, and 331, such as L234F, L235E, and P331S or a combination of amino acids 318, 320, and 322, such as E318A, K320A, and K322A.
• As an example a masking moiety comprising SEQ ID NO: 66 can be combined with a substrate comprising SEQ ID NO: 294, and a VL region comprising SEQ ID NO: 39 in combination with a human kappa constant domain comprising SEQ ID NO: 61 to produce a light chain, which may or may not include linker regions. One such example is SEQ ID NO: 380, although other embodiments having longer linker sequences are also contemplated. In some embodiments, for example, a VH region comprising SEQ ID NO: 21 can be combined a with human immunoglobulin heavy chain constant domain to give an IgG1 heavy chain (SEQ ID NO: 2048), an IgG4 heavy chain (SEQ ID NO: 2051), an IgG4 S228P heavy chain (SEQ ID NO: 2047), a mutated IgG1 N297A heavy chain (SEQ ID NO: 2049) or a mutated IgG1 N297Q heavy chain (SEQ ID NO: 2050). Co-expression of SEQ ID NO: 380 with SEQ ID NO: 2048 will yield an IgG1 anti-PD-1 activatable antibody. Co-expression of SEQ ID NO: 380 with SEQ ID NO: 2051 will yield an IgG4 anti-PD-1 activatable antibody. Co-expression of SEQ ID NO: 380 with SEQ ID NO: 2047 will yield an IgG4S228P anti-PD-1 activatable antibody. Co-expression of SEQ ID NO: 380 with SEQ ID NO: 2049 will yield an IgG1 N297A anti-PD-1 activatable antibody. Co-expression of SEQ ID NO: 380 with SEQ ID NO: 2050 will yield an IgG1 N297Q anti-PD-1 activatable antibody.
• In some embodiments, a masking moiety comprising SEQ ID NO: 99 is combined with a substrate comprising SEQ ID NO: 214 and a VL region comprising SEQ ID NO: 47 in combination with a human kappa constant domain comprising SEQ ID NO: 61 to produce a light chain comprising SEQ ID NO: 2055. In some embodiments, spacer QGQSGQG (SEQ ID NO: 362) is added to the N-terminus of SEQ ID NO: 2055 to form SEQ ID NO: 2054. In some embodiments, a masking moiety comprising SEQ ID NO: 99 is combined with a substrate comprising SEQ ID NO: 1100 and a VL region comprising SEQ ID NO: 47 in combination with a human kappa constant domain comprising SEQ ID NO: 61 to produce a light chain comprising SEQ ID NO: 2057. In some embodiments, spacer QGQSGQG (SEQ ID NO: 362) is added to the N-terminus of SEQ ID NO: 2057 to form SEQ ID NO: 2056. In some embodiments, a masking moiety comprising SEQ ID NO: 99 is combined with a substrate comprising SEQ ID NO: 1101, and a VL region comprising SEQ ID NO: 47 in combination with a human kappa constant domain comprising SEQ ID NO: 61 to produce a light chain comprising SEQ ID NO: 2059. In some embodiments, spacer QGQSGQG (SEQ ID NO: 362) is added to the N-terminus of SEQ ID NO: 2059 to form SEQ ID NO: 2058. In some embodiments, a VH region comprising SEQ ID NO: 21 can be combined with an IgG4 S228P human immunoglobulin heavy chain constant domain comprising SEQ ID NO: 63 to produce a heavy chain comprising SEQ ID NO: 2052. In some embodiments, the C-terminal lysine of SEQ ID NO: 2052 is missing to form an amino acid sequence having SEQ ID NO: 2053. Co-expression of any one of these light chains with any one of these heavy chains will lead to production of an activatable antibody of the embodiments.
• Constant region amino acid sequences are shown below in SEQ ID NO: 381, 382, 383, and 1807.

• IgG1 Hc CH1-end amino acid sequence:
  (SEQ ID NO: 381)
  ASTKGPSVFPLAPSSKSTSGGTAALGCLVKDYFPEPVTVSWNSGALTSGVHTFPAVLQSSGLYS
  LSSVVTVPSSSLGTQTYICNVNHKPSNTKVDKKVEPKSCDKTHTCPPCPAPELLGGPSVFLFPP
  KPKDTLMISRTPEVTCVVVDVSHEDPEVKFNWYVDGVEVHNAKTKPREEQY STYRVVSVLTVL
  HQDWLNGKEYKCKVSNKALPAPIEKTISKAKGQPREPQVYTLPPSREEMTKNQVSLTCLVKGFY
  PSDIAVEWESNGQPENNYKTTPPVLDSDGSFFLYSKLTVDKSRWQQGNVFSCSVMHEALHNHYT
  QKSLSLSPG
  IgG1NA CH1-end amino acid sequence:
  (SEQ ID NO: 382)
  ASTKGPSVFPLAPSSKSTSGGTAALGCLVKDYFPEPVTVSWNSGALTSGVHTFPAVLQSSGLYS
  LSSVVTVPSSSLGTQTYICNVNHKPSNTKVDKKVEPKSCDKTHTCPPCPAPELLGGPSVFLFPP
  KPKDTLMISRTPEVTCVVVDVSHEDPEVKFNWYVDGVEVHNAKTKPREEQY STYRVVSVLTVL
  HQDWLNGKEYKCKVSNKALPAPIEKTISKAKGQPREPQVYTLPPSREEMTKNQVSLTCLVKGFY
  PSDIAVEWESNGQPENNYKTTPPVLDSDGSFFLYSKLTVDKSRWQQGNVFSCSVMHEALHNHYT
  QKSLSLSPG
  IgG1NQ CH1-end amino acid sequence:
  (SEQ ID NO: 1807)
  ASTKGPSVFPLAPSSKSTSGGTAALGCLVKDYFPEPVTVSWNSGALTSGVHTFPAVLQSSGLYS
  LSSVVTVPSSSLGTQTYICNVNHKPSNTKVDKKVEPKSCDKTHTCPPCPAPELLGGPSVFLFPP
  KPKDTLMISRTPEVICVVVDVSHEDPEVKFNWYVDGVEVHNAKTKPREEQY STYRVVSVLTVL
  HQDWLNGKEYKCKVSNKALPAPIEKTISKAKGQPREPQVYTLPPSREEMTKNQVSLTCLVKGFY
  PSDIAVEWESNGQPENNYKTTPPVLDSDGSFFLYSKLTVDKSRWQQGNVFSCSVMHEALHNHYT
  QKSLSLSPG
  IgG4 Hc CH1-end amino acid sequence:
  (SEQ ID NO: 383)
  ASTKGPSVFPLAPCSRSTSESTAALGCLVKDYFPEPVTVSWNSGALTSGVHTFPAVLQSSGLYS
  LSSVVTVPSSSLGTKTYTCNVDHKPSNTKVDKRVESKYGPPCP CPAPEFLGGPSVFLFPPKPK
  DTLMISRTPEVTCVVVDVSQEDPEVQFNWYVDGVEVHNAKTKPREEQFNSTYRVVSVLTVLHQD
  WLNGKEYKCKVSNKGLPSSIEKTISKAKGQPREPQVYTLPPSQEEMTKNQVSLTCLVKGFYPSD
  IAVEWESNGQPENNYKTTPPVLDSDGSFFLYSRLTVDKSRWQEGNVFSCSVMHEALHNHYTQKS
  LSLSLG
  Light Chain (Lc) amino acid sequence:
  AMSGCSWSAFCPYLA[X1]nLSGRSDNH[X2]nDIQLTQSPSSLSASVGDRVTITCRASESVD
  NYGISFMNWFQQKPGKAPKLLIYAASNQGSGVPSRFSGSGSGTDFTLTISSMQPEDFATYYC
  QQSKDVPWTFGQGTKLEIKRTVAAPSVFIFPPSDEQLKSGTASVVCLLNNFYPREAKVQWKV
  DNALQSGNSQESVTEQDSKDSTYSLSSTLTLSKADYEKHKVYACEVTHQGLSSPVTKSFNRG
  EC
  where each of [X1]n and [X2]n independently can be a
  linking peptide of between 0 and 20 amino acids (SEQ ID NO:
  380), or any other suitable length.
  IgG4 S228P Heavy Chain (Hc) amino acid sequence:
  (SEQ ID NO: 2047)
  EVQLVESGGGLVQPGGSLRLSCAASGFTFSGYAMSWVRQAPGKGLEWVAYISNSGGNAHYADSV
  KGRFTISRDNSKNTLYLQMNSLRAEDTAVYYCTREDYGTSPFVYWGQGTLVTVSSASTKGPSVF
  PLAPCSRSTSESTAALGCLVKDYFPEPVTVSWNSGALTSGVHTFPAVLQSSGLYSLSSVVTVPS
  SSLGTKTYTCNVDHKPSNTKVDKRVESKYGPPCPPCPAPEFLGGPSVFLFPPKPKDTLMISRTP
  EVTCVVVDVSQEDPEVQFNWYVDGVEVHNAKTKPREEQFNSTYRVVSVLTVLHQDWLNGKEYKC
  KVSNKGLPSSIEKTISKAKGQPREPQVYTLPPSQEEMTKNQVSLTCLVKGFYPSDIAVEWESNG
  QPENNYKTTPPVLDSDGSFFLYSRLTVDKSRWQEGNVFSCSVMHEALHNHYTQKSLSLSLGK
  IgG1 Heavy Chain (Hc) amino acid sequence:
  (SEQ ID NO: 2048)
  EVQLVESGGGLVQPGGSLRLSCAASGFTFSGYAMSWVRQAPGKGLEWVAYISNSGGNAHYADSV
  KGRFTISRDNSKNTLYLQMNSLRAEDTAVYYCTREDYGTSPFVYWGQGTLVTVSS
  ASTKGPSVFPLAPSSKSTSGGTAALGCLVKDYFPEPVTVSWNSGALTSGVHTFPAVLQSSGLYS
  LSSVVTVPSSSLGTQTYICNVNHKPSNTKVDKKVEPKSCDKTHTCPPCPAPELLGGPSVFLFPP
  KPKDTLMISRTPEVICVVVDVSHEDPEVKFNWYVDGVEVHNAKTKPREEQY STYRVVSVLTVL
  HQDWLNGKEYKCKVSNKALPAPIEKTISKAKGQPREPQVYTLPPSREEMTKNQVSLTCLVKGFY
  PSDIAVEWESNGQPENNYKTTPPVLDSDGSFFLYSKLTVDKSRWQQGNVFSCSVMHEALHNHYT
  QKSLSLSPG
  IgG1NA Hc amino acid sequence:
  (SEQ ID NO: 2049)
  EVQLVESGGGLVQPGGSLRLSCAASGFTFSGYAMSWVRQAPGKGLEWVAYISNSGGNAHYADSV
  KGRFTISRDNSKNTLYLQMNSLRAEDTAVYYCTREDYGTSPFVYWGQGTLVTVSS
  ASTKGPSVFPLAPSSKSTSGGTAALGCLVKDYFPEPVTVSWNSGALTSGVHTFPAVLQSSGLYS
  LSSVVTVPSSSLGTQTYICNVNHKPSNTKVDKKVEPKSCDKTHTCPPCPAPELLGGPSVFLFPP
  KPKDTLMISRTPEVICVVVDVSHEDPEVKFNWYVDGVEVHNAKTKPREEQY STYRVVSVLTVL
  HQDWLNGKEYKCKVSNKALPAPIEKTISKAKGQPREPQVYTLPPSREEMTKNQVSLTCLVKGFY
  PSDIAVEWESNGQPENNYKTTPPVLDSDGSFFLYSKLTVDKSRWQQGNVFSCSVMHEALHNHYT
  QKSLSLSPG
  IgG1NQ Hc amino acid sequence:
  (SEQ ID NO: 2050)
  EVQLVESGGGLVQPGGSLRLSCAASGFTFSGYAMSWVRQAPGKGLEWVAYISNSGGNAHYADSV
  KGRFTISRDNSKNTLYLQMNSLRAEDTAVYYCTREDYGTSPFVYWGQGTLVTVSS
  ASTKGPSVFPLAPSSKSTSGGTAALGCLVKDYFPEPVTVSWNSGALTSGVHTFPAVLQSSGLYS
  LSSVVTVPSSSLGTQTYICNVNHKPSNTKVDKKVEPKSCDKTHTCPPCPAPELLGGPSVFLFPP
  KPKDTLMISRTPEVICVVVDVSHEDPEVKFNWYVDGVEVHNAKTKPREEQY STYRVVSVLTVL
  HQDWLNGKEYKCKVSNKALPAPIEKTISKAKGQPREPQVYTLPPSREEMTKNQVSLTCLVKGFY
  PSDIAVEWESNGQPENNYKTIPPVLDSDGSFFLYSKLTVDKSRWQQGNVFSCSVMHEALHNHYT
  QKSLSLSPG
  IgG4 Hc amino acid sequence:
  (SEQ ID NO: 2051)
  EVQLVESGGGLVQPGGSLRLSCAASGFTFSGYAMSWVRQAPGKGLEWVAYISNSGGNAHYADSV
  KGRFTISRDNSKNTLYLQMNSLRAEDTAVYYCTREDYGTSPFVYWGQGTLVTVSS
  ASTKGPSVFPLAPCSRSTSESTAALGCLVKDYFPEPVTVSWNSGALTSGVHTFPAVLQSSGLYS
  LSSVVTVPSSSLGTKTYTCNVDHKPSNTKVDKRVESKYGPPCP CPAPEFLGGPSVFLFPPKPK
  DTLMISRTPEVTCVVVDVSQEDPEVQFNWYVDGVEVHNAKTKPREEQFNSTYRVVSVLTVLHQD
  WLNGKEYKCKVSNKGLPSSIEKTISKAKGQPREPQVYTLPPSQEEMTKNQVSLTCLVKGFYPSD
  IAVEWESNGQPENNYKTIPPVLDSDGSFFLYSRLTVDKSRWQEGNVFSCSVMHEALHNHYTQKS
  LSLSLG
  Heavy Chain 1 Amino Acid Sequence (SEQ ID NO: 2052):
  EVQLVESGGGLVQPGGSLRLSCAASGFTFSGYAMSWVRQAPGKGLEWVAYISNSGGNA
  HYADSVKGRFTISRDNSKNTLYLQMNSLRAEDTAVYYCTREDYGTSPFVYWGQGTLVT
  VSSASTKGPSVFPLAPCSRSTSESTAALGCLVKDYFPEPVTVSWNSGALTSGVHTFPAVL
  QSSGLYSLSSVVTVPSSSLGTKTYTCNVDHKPSNTKVDKRVESKYGPPCPPCPAPEFLGG
  PSVFLFPPKPKDTLMISRTPEVTCVVVDVSQEDPEVQFNWYVDGVEVHNAKTKPREEQF
  NSTYRVVSVLTVLHQDWLNGKEYKCKVSNKGLPSSIEKTISKAKGQPREPQVYTLPPSQ
  EEMTKNQVSLTCLVKGFYPSDIAVEWESNGQPENNYKTTPPVLDSDGSFFLYSRLTVDK
  SRWQEGNVFSCSVMHEALHNHYTQKSLSLSLGK
  Heavy Chain 2 Amino Acid Sequence (SEQ ID NO: 2053):
  EVQLVESGGGLVQPGGSLRLSCAASGFTFSGYAMSWVRQAPGKGLEWVAYISNSGGNA
  HYADSVKGRFTISRDNSKNTLYLQMNSLRAEDTAVYYCTREDYGTSPFVYWGQGTLVT
  VSSASTKGPSVFPLAPCSRSTSESTAALGCLVKDYFPEPVTVSWNSGALTSGVHTFPAVL
  QSSGLYSLSSVVTVPSSSLGTKTYTCNVDHKPSNTKVDKRVESKYGPPCPPCPAPEFLGG
  PSVFLFPPKPKDTLMISRTPEVTCVVVDVSQEDPEVQFNWYVDGVEVHNAKTKPREEQF
  NSTYRVVSVLTVLHQDWLNGKEYKCKVSNKGLPSSIEKTISKAKGQPREPQVYTLPPSQ
  EEMTKNQVSLTCLVKGFYPSDIAVEWESNGQPENNYKTTPPVLDSDGSFFLYSRLTVDK
  SRWQEGNVFScSVMHEALHNHYTQKSLSLSLG
  Light Chain 1 Amino Acid Sequence with spacer (SEQ ID NO: 2054):
  [QGQSGQG][TSYCSIEHYPCNTHHGGGSSGGSISSGLLSGRSDNHGGGSDIQLTQSPSSLS
  ASVGDRVTITCRASESVDAYGISFMNWFQQKPGKAPKLLIYAASNQGSGVPSRFSGSGS
  GTDFTLTISSMQPEDFATYYCQQSKDVPWTFGQGTKLEIKRTVAAPSVFIFPPSDEQLKS
  GTASVVCLLNNFYPREAKVQWKVDNALQSGNSQESVTEQDSKDSTYSLSSTLTLSKAD
  YEKHKVYACEVTHQGLSSPVTKSFNRGEC]
  Light Chain 1 Amino Acid Sequence without spacer (SEQ ID NO: 2055):
  TSYCSIEHYPCNTHHGGGSSGGSISSGLLSGRSDNHGGGSDIQLTQSPSSLSASVGDRVTI
  TCRASESVDAYGISFMNWFQQKPGKAPKLLIYAASNQGSGVPSRFSGSGSGTDFTLTISS
  MQPEDFATYYCQQSKDVPWTFGQGTKLEIKRTVAAPSVFIFPPSDEQLKSGTASVVCLL
  NNFYPREAKVQWKVDNALQSGNSQESVTEQDSKDSTYSLSSTLTLSKADYEKHKVYAC
  EVTHQGLSSPVTKSFNRGEC
  Light Chain 2 Amino Acid Sequence with spacer (SEQ ID NO: 2056):
  [QGQSGQG][TSYCSIEHYPCNTHHGGGSSGGSISSGLLSGRSDNPGGGSDIQLTQSPSSLS
  ASVGDRVTITCRASESVDAYGISFMNWFQQKPGKAPKLLIYAASNQGSGVPSRFSGSGS
  GTDFTLTISSMQPEDFATYYCQQSKDVPWTFGQGTKLEIKRTVAAPSVFIFPPSDEQLKS
  GTASVVCLLNNFYPREAKVQWKVDNALQSGNSQESVTEQDSKDSTYSLSSTLTLSKAD
  YEKHKVYACEVTHQGLSSPVTKSFNRGEC]
  Light Chain 2 Amino Acid Sequence without spacer (SEQ ID NO: 2057):
  TSYCSIEHYPCNTHHGGGSSGGSISSGLLSGRSDNPGGGSDIQLTQSPSSLSASVGDRVTIT
  CRASESVDAYGISFMNWFQQKPGKAPKLLIYAASNQGSGVPSRFSGSGSGTDFTLTISSM
  QPEDFATYYCQQSKDVPWTFGQGTKLEIKRTVAAPSVFIFPPSDEQLKSGTASVVCLLNN
  FYPREAKVQWKVDNALQSGNSQESVTEQDSKDSTYSLSSTLTLSKADYEKHKVYACEV
  THQGLSSPVTKSFNRGEC
  Light Chain 3 Amino Acid Sequence with spacer (SEQ ID NO: 2058):
  [QGQSGQG][TSYCSIEHYPCNTHHGGGSSGGSISSGLLSGRSANPGGGSDIQLTQSPSSLS
  ASVGDRVTITCRASESVDAYGISFMNWFQQKPGKAPKLLIYAASNQGSGVPSRFSGSGS
  GTDFTLTISSMQPEDFATYYCQQSKDVPWTFGQGTKLEIKRTVAAPSVFIFPPSDEQLKS
  GTASVVCLLNNFYPREAKVQWKVDNALQSGNSQESVTEQDSKDSTYSLSSTLTLSKAD
  YEKHKVYACEVTHQGLSSPVTKSFNRGEC]
  Light Chain 3 Amino Acid Sequence without spacer (SEQ ID NO: 2059):
  TSYCSIEHYPCNTHHGGGSSGGSISSGLLSGRSANPGGGSDIQLTQSPSSLSASVGDRVTIT
  CRASESVDAYGISFMNWFQQKPGKAPKLLIYAASNQGSGVPSRFSGSGSGTDFTLTISSM
  QPEDFATYYCQQSKDVPWTFGQGTKLEIKRTVAAPSVFIFPPSDEQLKSGTASVVCLLNN
  FYPREAKVQWKVDNALQSGNSQESVTEQDSKDSTYSLSSTLTLSKADYEKHKVYACEV
  THQGLSSPVTKSFNRGEC

Example 10: Evaluation of Efficiency of Masking Moieties
• This example describes activatable anti-PD-1 antibodies of the disclosure with reduced binding to hPD-1.
• Masking the ability of an antibody to bind to its antigen is an example of inhibition of binding. The extent of inhibition is dependent on the affinity of the antibody for its antigen, the affinity of the masking moiety (also referred to herein as the mask) for the antibody and the concentration of all reactants. Local concentrations of the tethered peptide mask (inhibitor) is very high in the activatable antibody context, on the order of 10 mM, therefore moderate affinity peptides would effectively mask activatable antibody antigen binding.
• Masking efficiencies were evaluated by standard plate ELISA. Briefly, human PD-1-Fc (R and D systems, Minneapolis, Minn.) was adsorbed to the wells of a 96-well ELISA plate. Purified anti-PD-1 antibodies and activatable antibodies were applied to the plate in serial dilution and allowed to bind. Bound antibody and activatable antibodies were detected with anti-human IgG-HRP conjugate, FAb-specific (Sigma, St Louis, Mo.) and visualized with the chromogenic substrate TMB (Thermo Scientific, Rockford, Ill.). Shown are plots of binding isotherms for anti-PD-1 A1.4 and anti-PD-1 A1.5 activatable antibodies (FIGS. 14-18). Plots were generated in Prizm (Sigma Plot); the data were fit to a model of single site saturation binding, and the equilibrium dissociation constant, K_d, was determined. Masking efficiency was calculated by dividing the K_d for binding of the activatable antibodies by the K_d of the parental antibody. The masking efficiency (ME) values for the tested antibodies are shown in Table 14 and Table 15 below (masking moiety PD001 is also referred to herein as PD01 and/or PD-01; masking moiety PD002 is also referred to herein as PD02 and/or PD-02, and so on), and the apparent K_d (nM) and masking efficiency (ME) values for the tested activatable antibodies are shown in Table 26:

• TABLE 14
  Masking efficiency values for activatable
  antibodies tested in FIG. 14

  	Mask	ME
  	PD01	25
  	PD02	18
  	PD03	5
  	PD08	13
  	PD09	2
  	PD-10	13

• TABLE 15
  Masking efficiency values for activatable antibodies tested in FIG. 18

  Mask	ME
  None	1
  PD06	30
  PD09	2
  PD-12	10
  PD-17	20
  PD-19	30
  PD25	30
  PD26	20
  PD28	25
  PD34	42

• TABLE 26
  Apparent Kd and Masking efficiency values for activatable
  antibodies tested in FIG. 15

  Molecule	Apparent KD, nM	Masking Efficiency

  A1.5 (n = 5 avg)	1.8
  PD01	348	193
  PD02	21	12
  PD03	109	61
  PD05	68	38
  PD06	71	39
  PD08	55	31
  PD09	10	6
  PD10	54	30
  PD11	67	37
  PD12	25	14
  PD13	151	84
  PD14	100	56
  PD15	117	65
  PD16	57	32
  PD17	22	12
  PD18	75	42
  PD19	93	52
  PD20	77	43
  PD21	49	27
  PD22	41	23
  PD23	31	17
  PD24	92	51

Example 11: Anti-PD-1 Activatable Antibodies of the Embodiments are Functionally Masked in a Human T-Cell Restimulation Assay
• This example describes the effect of masking moieties on the biological function of the anti-PD-1 antibody. (FIG. 19)
• PBMCs from a CMV-positive donor (Hemacare) were plated at 2×10⁵ cells/well in the presence of CMV viral lysate (Astarte) and either anti-PD-1 antibody A1.5, an anti-PD-1 activatable antibody of the disclosure, or hIgG4 isotype control antibody. After four days, supernatant was removed from each well and IFN-gamma levels were assayed using IFN-gamma ELISA kit (Life Technologies, Carlsbad, Calif.). Anti-PD-1 A1.5 activatable antibodies increased CMV-stimulated IFN-gamma secretion compared with control hIgG4 but with decreased potency relative to anti-PD-1 A1.5 parental antibody (FIG. 19).
Example 12: Anti Mouse PD-1 J43v2 mIgG2a Antibody Binds Mouse PD-1 and Blocks Mouse PD-L1 and Mouse PD-L2 Binding
• This example demonstrates that Armenian hamster anti mouse PD-1 J43 antibody (U.S. Pat. No. 7,858,746; Agata et al, 1996, International Immunology, Vol. 8 No. 5 pp 765-77) can be functionally expressed as a mouse IgG2a antibody.
• Anti-mouse PD-1 antibody J43 was reformatted as a hamster LC (SEQ ID NO: 543 amino acid; SEQ ID NO: 544 or SEQ ID NO: 545 nucleotide), mouse IgG2a antibody by fusion of the heavy chain variable domain to mIgG2a, resulting in amino acid SEQ ID NO 546, nucleotide sequence SEQ ID NO 547. Full length J43v2 mIgG2a (also referred to as J43v2, J43 m2a and J43v2 m2a) was expressed by transient transfection of HEK293 cells and purified from the culture supernatant by Protein G chromatography. One embodiment of this disclosure is an antibody comprising a light chain comprising amino acid sequence SEQ ID NO: 543. One embodiment of this disclosure is an antibody comprising a heavy chain comprising amino acid sequence SEQ ID NO: 546. One embodiment of this disclosure is an antibody comprising a light chain comprising amino acid sequence SEQ ID NO: 543 and a heavy chain comprising amino acid sequence SEQ ID NO: 546. One embodiment of this disclosure is an antibody comprising the CDRs of an antibody comprising a light chain comprising amino acid sequence SEQ ID NO: 543 and a heavy chain comprising amino acid sequence SEQ ID NO: 546.
• Functionality was assayed by binding of J43v2 m2a to HEK293 cells expressing mouse PD-1 and confirmation that binding of J43v2 m2a to HEK293-mPD-1 inhibited binding of biotinylated mPD-L1 and biotinylated mPD-L2 to HEK293-mPD-1 (FIG. 20). About 100,000 mPD-1 HEK293 cells were transferred to a U-bottom 96-well plate. For the binding experiment, a 1:4 titration of J43v2 m2a antibody starting at 150 nM was added to cells. For blocking experiments, 20 nM of biotinylated-mPD-L1-Fc or 20 nM of biotinylated-mPD-L2-Fc were premixed with a 1:4 titration of J43v2 m2a starting at 150 nM and added to cells. Both were incubated for 1 hour on ice and cells were washed 3 times. J43v2 m2a antibody binding was detected using an anti-mouse secondary antibody (Jackson Immunoresearch, West Grove, Pa.). For the blocking experiment, biotinylated-PD-L1 or biotinylated-PD-L2 was detected using streptavidin-PE (Life Technologies, Carlsbad, Calif.). Both binding and blocking were incubated for 30 minutes on ice and were washed and read on a flow cytometer (MACSQuant).
Example 13: J43v2 m2a Induces Diabetes in NOD Mouse Model
• In this Example, anti-PD-1 J43v2 m2a antibody was confirmed to induce diabetes in the NOD mouse model.
• Antibody J43v2 m2a was confirmed to induce diabetes in NOD mice as follows. The NOD mice, substrain NOD/ShiLtJ were obtained from Jackson Laboratory at 8 weeks and acclimated on site for 2 weeks. At 10 weeks, mice were checked for diabetes prior to enrollment, grouped, and dosed as set forth in Table 16. FIG. 21 shows the dose-dependent induction of diabetes in NOD mice by J43v2 m2a. At day eight after a single dose, 100% of mice in the mIgG2a isotype control group remained non-diabetic, while 0%, 14% and 86% of the 20 mg/kg, 3 mg/kg and 1 mg/kg groups, respectively, remained non-diabetic.

• TABLE 16
  Study design

  					Dose
  				Dose	volume
  Group	Count	Gender	Treatment	(mg/kg)	(mL/kg)	Schedule	Route

  1	7	F	mIgG2a (C1.18.4)	20	10	q7dx1	IP
  2	7	F	Anti-PD-1 (J43v2)	20	10	q7dx1	IP
  3	7	F	Anti-PD-1 (J43v2)	5	10	q7dx1	IP
  4	7	F	Anti-PD-1 (J43v2)	1	10	q7dx1	IP

Example 14: Activatable Anti-Mouse PD-1 J43 Masking Moieties
• This example describes identification of masking moieties (MM) that reduce binding of anti-PD-1 J43 antibody to its target.
• Anti-PD-1 J43v2 mIgG2a was used to screen libraries using a method similar to that described in PCT International Publication Number WO 2010/081173, published 15 Jul. 2010. The screening consisted of one round of MACS and three rounds of FACS sorting. For the initial MACS, approximately 1×10¹² cells were incubated with J43v2 m2a antibody at a concentration of 200 nM, and approximately 9×10⁷ binders were collected using Protein-G Dynabeads (Life Technologies, Carlsbad, Calif.). FACS rounds were conducted labeling cells with DyLight 650 (Thermo-Fisher) labeled J43v2 m2a antibody and collecting cells with strongest fluorescence as follows: 200 nM J43-650 collecting brightest 3% for FACS round 1 (F1), 20 nM J43-650 collecting brightest 8% for FACS round 2 (F2) and 1 nM J43-650 collecting two populations, the brightest 20% and the brightest 0.5% for FACS round 3 (F3-20 and F3-0.5). Individual peptide clones from F2, F3-20 and F3-0.5 were identified by sequence analysis (Table 17), and selected peptide clones MP001-MP014 were subsequently verified for their ability to bind J43-650 (masking moiety MP001 is also referred to herein as MP01 and/or MP-01; masking moiety MP002 is also referred to herein as MP02 and/or MP-02, and so on).

• TABLE 17
  Masking moiety sequences

  	Mask	Amino Acid Sequence	SEQ ID NO:
  	MP001	DYTYCRWVNWCLSGV	384
  	MP002	ILCPEDPWGHKCKLP	385
  	MP003	TNIWSCQTYCDHKHK	386
  	MP004	SDHKCKLQNCMNTKV	387
  	MP005	PGNCHPMQKEMCQFI	388
  	MP006	VEHLCYTHNKCKHPD	389
  	MP007	TIPRCGQHPKCKDTL	390
  	MP008	ACRICQDHPKTKWNS	391
  	MP009	LIQCTGNLDHKCKHY	392
  	MP010	IPCHHSADHKHKCTS	393
  	MP011	SRQICADYNCHNKYK	394
  	MP012	QPCNPQIDHKIKCIY	395
  	MP013	HYTICMTHNKCKDMA	396
  	MP014	ANSCLAVEHKCKHNY	397
  	MP015	AALHCTEHKCKNHIK	398
  	MP016	APCIINTVDWKSCEI	399
  	MP017	ATNWCTHKQKCKQDM	400
  	MP018	DCYNEHKLKTRVCNN	401
  	MP019	DEMQCSHKQKCTNSK	402
  	MP020	DVGICSQHNKCKPTK	403
  	MP021	EKYCSSDDHKCKITL	404
  	MP022	ELECSHNKVKNCIQI	405
  	MP023	ELHPCNTHKCKPIVN	406
  	MP024	EVGSCNHPKCKSNNY	407
  	MP025	EYSPSLAHPKLKDNA	408
  	MP026	FESLHPKGKHPEDLG	409
  	MP027	FPLCVRADRVCGDAQ	410
  	MP028	FQAPPASHNKLKPSL	411
  	MP029	GAIDSCHHKCKSPHY	412
  	MP030	GKIYTCEHNCTFGYS	413
  	MP031	HCTVNNHSSDHKCKI	414
  	MP032	HGTQCTHNKCKPILS	415
  	MP033	HIGWCLHPKCKTTTT	416
  	MP034	HLRTCIQKWCEHKMK	417
  	MP035	HTDCTMMSNHKCKIN	418
  	MP036	IRQQCTALACLLKVH	419
  	MP037	KGCSTHKMRAYCNQM	420
  	MP038	KMFTPCKIWCNNSYN	421
  	MP039	KTMCSGHKQKCNNSS	422
  	MP040	LACHSASLVDHKCKL	423
  	MP041	LCNVSMDHKHKPCYL	424
  	MP042	LGLNCFSEHKCKEHM	425
  	MP043	LGTCTHKHKNCNYTL	426
  	MP044	LHEGCTTHNKCKPIA	427
  	MP045	LKRSCTGHWTCYTNW	428
  	MP046	LQRCTHKEKYCHAIH	429
  	MP047	LSHCYDHKRKCSYIV	430
  	MP048	LSKCHNKEKNCSNNN	431
  	MP049	MDTCEMHKQKCRPSF	432
  	MP050	MHNECLTHKCKVPIT	433
  	MP051	MLTLCNTNACHKEKN	434
  	MP052	MRPCLNNLEHKCKHY	435
  	MP053	MSRCPTHKMKCSLNI	436
  	MP054	MWICQEHKLKCMTDT	437
  	MP055	MYYCKRRSAFYCTLN	438
  	MP056	NDCQHDKQMHKCKMH	439
  	MP057	NFGPCPMLLGCFGFR	440
  	MP058	NHTDCSHPKCKSHDS	441
  	MP059	NLNCPHKQKNCDKYH	442
  	MP060	NPQCTPIDHKCKTHH	443
  	MP061	NTTSCTHPKCKHQGK	444
  	MP062	NVGGCDNYGCHKLKN	445
  	MP063	PCSPGNLTWDHKCKY	446
  	MP064	PFTKCHGFNKCKEHT	447
  	MP065	PGDKCTHKEKCYYNN	448
  	MP066	PNICNLDHKRKCRIN	449
  	MP067	PQLACKHPKCKDAGN	450
  	MP068	PSCTMWTHGGVCKHA	451
  	MP069	PSHRHPLAKPGFRVE	452
  	MP070	PTCFKTHNKSKCNRV	453
  	MP071	PTPVCHHNFHCFGYD	454
  	MP072	QATCQWKKRSKCHNK	455
  	MP073	QHSWCQHKAKCNYGN	456
  	MP074	QNCSPTYTTHKCKLT	457
  	MP075	QSSNCEHKRKCSSTS	458
  	MP076	RPCLLGLVPDHKCKL	459
  	MP077	RRSCMRSINTCKQKY	460
  	MP078	RSSCPTVTPQNCENQ	461
  	MP079	RTMCLDLNHKCKPSN	462
  	MP080	RTYWCTNHNKCKHNM	463
  	MP081	RVENCEHNQYCHKWK	464
  	MP082	SCHEDDHKNKNICSL	465
  	MP083	SDTCVMNHPKCKRDN	466
  	MP084	SSTCFHPNQKECMTK	467
  	MP085	SSYCGGITMRCRRAM	468
  	MP086	STGYCTYVNWCNYTN	469
  	MP087	THKCKLHLQVCTQTT	470
  	MP088	TMNCTHPKQKCQHTN	471
  	MP089	TNVLCESHNCDHKNK	472
  	MP090	TQHAASLGVEHKSKI	473
  	MP091	TQLPCFDDHKCKNTN	474
  	MP092	TSDSCMRQKCEHKEK	475
  	MP093	TTCDDHKYKHKCAQL	476
  	MP094	TTCGAHKEKQHCIYT	477
  	MP095	TTYCAYWHNKCKFET	478
  	MP096	VGPTCGHAKCKQSEV	479
  	MP097	VSHPCNTHKCKTNIV	480
  	MP098	WDCRNTSHPKLKCHN	481
  	MP099	WSPCNSDHKRKCNNG	482
  	MP100	YANMSCEYDCHKMKY	483
  	MP101	YANPCTHKEKCHFKN	484
  	MP102	YDCSPSWTHPKCKHK	485
  	MP103	YGWTCTTHPKCKTTN	486
  	MP104	YQKCHPKAKDCGNNT	487
  	MP105	YWECPNMEHNKCKNN	488
  	MP106	PMGNRYCVLDHPKLK	489
  	MP107	GHKSCCQKHCEYTQT	490
  	MP108	LYLEMCSCCCWESIT	491
  	MP109	ACQAQHCYKTYACKP	492
  	MP110	CCYTCSVHPKCKNQL	493
  	MP111	CKHRCSHKEKCPANH	494
  	MP112	CHVLFCLMQCCRWSL	495
  	MP113	LNSSLVFDHPKAKPN	496
  	MP114	MCLLCRSKFGCKVKG	497
  	MP115	IICNDHKCKQNQCNN	498
  	MP116	IRCSLRDSLCGCERM	499
  	MP117	TSCQPPKHKCTCNHG	500
  	MP118	TQCPHRCVKPNCWLH	501
  	MP119	KCCETKRNHKHCTYK	502
  	MP120	LPHCCHKAKHCNHTS	503
  	MP121	PAMCAAIHEKCCIKV	504
  	MP122	PRSCGNQLCPCHYYK	505
  	MP123	TNKCSCNHNMKCINY	506
  	MP124	VETCCQHNKCKYPFI	507
  	MP125	IFCCSNHEDHKCKTN	508
  	MP126	VCRLICPLTCVIGVG	509
  	MP127	FHGCCSVYSCLTNPG	510
  	MP128	ALACHPKQKPLEGQL	511
  	MP129	SIICCATSSCPLKHL	512
  	MP130	APCCRPHKEKPIDSR	513
  	MP131	WELCCPSADCRVAMG	514

Example 15: Characterization of Activatable Anti-Mouse PD-1 Antibodies
• This example describes activatable anti-PD-1 antibodies of the disclosure with reduced binding to hPD-1 compared to binding by parental antibody.
• Masking efficiencies were evaluated by standard plate ELISA. Briefly, mouse PD-1-Fc (R and D systems, Minneapolis, Minn.) was adsorbed to the wells of a 96-well ELISA plate. Purified J43v2 and activatable J43v2 antibodies comprising the indicated masks, cleavable moiety 2001, and antibody J43v2 were applied to the plate in serial dilution and allowed to bind. Bound antibody and activatable antibodies were detected with anti-mouse IgG-HRP conjugate (Sigma, St Louis, Mo.) and visualized with the chromogenic substrate TMB (Thermo Scientific, Rockford, Ill.). Plots were generated in Prizm (Sigma Plot). All activatable J43 antibodies showed strongly decreased binding compared with the parental J43 (FIG. 22).
• In some embodiments, the activatable antibody also includes a spacer sequence. In some embodiments, the spacer is joined directly to the MM of the activatable antibody. In some embodiments, the spacer is joined directly to the MM of the activatable antibody in the structural arrangement from N-terminus to C-terminus of spacer-MM-CM-AB. In some embodiments, the spacer joined directly to the N-terminus of MM of the activatable antibody is selected from the group consisting of QGQSGQG (SEQ ID NO: 362), QGQSGQ (SEQ ID NO: 913), QGQSG (SEQ ID NO: 914), QGQS (SEQ ID NO: 915), QGQ (SEQ ID NO: 916), QG (SEQ ID NO: 917), and Q. In some embodiments, the spacer includes at least the amino acid sequence QGQSGQG (SEQ ID NO: 362). In some embodiments, the spacer includes at least the amino acid sequence QGQSGQ (SEQ ID NO: 913). In some embodiments, the spacer includes at least the amino acid sequence QGQSG (SEQ ID NO: 914). In some embodiments, the spacer includes at least the amino acid sequence QGQS (SEQ ID NO: 915), In some embodiments, the spacer includes at least the amino acid sequence QGQ (SEQ ID NO: 916). In some embodiments, the spacer includes at least the amino acid sequence QG (SEQ ID NO: 917). In some embodiments, the spacer includes at least the amino acid residue Q. In some embodiments, the activatable antibody does not include a spacer sequence.
• Additional examples of spacers include GQSGQG (SEQ ID NO: 2042), QSGQG (SEQ ID NO: 2043), SGQG (SEQ ID NO: 2044), GQG(SEQ ID NO: 2045), QG(SEQ ID NO: 2046), and G.
• While the sequences shown below include the spacer sequence of SEQ ID NO: 362, those of ordinary skill in the art appreciate that the activatable anti-PD-1 antibodies of the disclosure can include any suitable spacer sequence, such as, for example, a spacer sequence selected from the group consisting of QGQSGQG (SEQ ID NO: 362), QGQSGQ (SEQ ID NO: 913), QGQSG (SEQ ID NO: 914), QGQS (SEQ ID NO: 915), QGQ (SEQ ID NO: 916), QG (SEQ ID NO: 917), and Q. Additional examples of spacers include GQSGQG (SEQ ID NO: 2042), QSGQG (SEQ ID NO: 2043), SGQG (SEQ ID NO: 2044), GQG(SEQ ID NO: 2045), QG(SEQ ID NO: 2046), and G. While the sequences shown below include the spacer sequence of SEQ ID NO: 362, those of ordinary skill in the art will also appreciate that activatable anti-PD-1 antibodies of the disclosure in some embodiments do not include a spacer sequence.
Activatable Anti-Mouse PD-1 Light Chain Variable Domains

• [spacer (SEQ ID NO: 362)][J43 MP001 2001 (SEQ ID NO: 999)] amino acid sequence:
  (SEQ ID NO: 515)
  [QGQSGQG][DYTYCRWVNWCLSGVGGGSSGGSISSGLLSGRSDNHGGGSYELTQPPSASVNVG
  ETVKITCSGDQLPKYFADWFHQRSDQTILQVIYDDNKRPSGIPERISGSSSGTTATLTIRDVRA
  EDEGDYYCFSGYVDSDSKLYVFGSGTQLTVL]
  J43 MP001 2001 amino acid sequence:
  (SEQ ID NO: 1077)
  DYTYCRWVNWCLSGVGGGSSGGSISSGLLSGRSDNHGGGSYELTQPPSASVNVGETVKITCSGD
  QLPKYFADWFHQRSDQTILQVIYDDNKRPSGIPERISGSSSGTTATLTIRDVRAEDEGDYYCFS
  GYVDSDSKLYVFGSGTQLTVL
  [spacer (SEQ ID NO: 918)][J43 MP001 2001 (SEQ ID NO: 1000)] nucleic acid sequence:
  (SEQ ID NO: 516)
  [CAAGGCCAGTCTGGCCAAGGT]GATTATACGTATTGCCGTTGGGTTAATTGGTGCTTGTCTG
  GGGTGGGAGGTGGCTCGAGCGGCGGCTCTATCTCTTCCGGACTGCTGTCCGGCAGATCCGACAA
  TCACGGCGGAGGCTCTTATGAGCTGACTCAGCCACCTTCAGCATCAGTCAATGTAGGAGAGACT
  GTCAAAATCACCTGCTCTGGGGACCAATTGCCGAAATATTTTGCAGATTGGTTTCATCAAAGGT
  CAGACCAGACCATTTTGCAAGTGATATATGATGATAATAAGCGCCCCTCGGGTATCCCTGAAAG
  AATCTCTGGGTCCAGCTCAGGGACAACAGCCACCTTGACCATCAGAGATGTCCGGGCTGAGGAT
  GAAGGTGACTATTACTGTTTCTCAGGATATGTTGATAGTGATAGCAAATTGTATGTTTTTGGCA
  GCGGAACCCAGCTCACCGTCCT
  [spacer (SEQ ID NO: 362)][J43 MP002 2001 (SEQ ID NO: 1001)] amino acid sequence:
  (SEQ ID NO: 517)
  [QGQSGQG][ILCPEDPWGHKCKLPGGGSSGGSISSGLLSGRSDNHGGGSYELTQPPSASVNVG
  ETVKITCSGDQLPKYFADWFHQRSDQTILQVIYDDNKRPSGIPERISGSSSGTTATLTIRDVRA
  EDEGDYYCFSGYVDSDSKLYVFGSGTQLTVL]
  J43 MP002 2001 amino acid sequence:
  (SEQ ID NO: 1078)
  ILCPEDPWGHKCKLPGGGSSGGSISSGLLSGRSDNHGGGSYELTQPPSASVNVGETVKITCSGD
  QLPKYFADWFHQRSDQTILQVIYDDNKRPSGIPERISGSSSGTTATLTIRDVRAEDEGDYYCFS
  GYVDSDSKLYVFGSGTQLTVL
  [spacer (SEQ ID NO: 918)][J43 MP002 2001 (SEQ ID NO: 1002)] nucleic acid sequence:
  (SEQ ID NO: 518)
  [CAAGGCCAGTCTGGCCAAGGT][ATTCTGTGCCCGGAGGATCCGTGGGGGCATAAGTGCAAGC
  TGCCTGGAGGTGGCTCGAGCGGCGGCTCTATCTCTTCCGGACTGCTGTCCGGCAGATCCGACAA
  TCACGGCGGAGGCTCTTATGAGCTGACTCAGCCACCTTCAGCATCAGTCAATGTAGGAGAGACT
  GTCAAAATCACCTGCTCTGGGGACCAATTGCCGAAATATTTTGCAGATTGGTTTCATCAAAGGT
  CAGACCAGACCATTTTGCAAGTGATATATGATGATAATAAGCGCCCCTCGGGTATCCCTGAAAG
  AATCTCTGGGTCCAGCTCAGGGACAACAGCCACCTTGACCATCAGAGATGTCCGGGCTGAGGAT
  GAAGGTGACTATTACTGTTTCTCAGGATATGTTGATAGTGATAGCAAATTGTATGTTTTTGGCA
  GCGGAACCCAGCTCACCGTCCTA
  [spacer (SEQ ID NO: 362)][J43 MP003 2001 (SEQ ID NO: 1003)] amino acid sequence:
  (SEQ ID NO: 519)
  [QGQSGQG][TNIWSCQTYCDHKHKGGGSSGGSISSGLLSGRSDNHGGGSYELTQPPSASVNVG
  ETVKITCSGDQLPKYFADWFHQRSDQTILQVIYDDNKRPSGIPERISGSSSGTTATLTIRDVRA
  EDEGDYYCFSGYVDSDSKLYVFGSGTQLTVL]
  J43 MP003 2001 amino acid sequence:
  (SEQ ID NO: 1079)
  TNIWSCQTYCDHKHKGGGSSGGSISSGLLSGRSDNHGGGSYELTQPPSASVNVGETVKITCSGD
  QLPKYFADWFHQRSDQTILQVIYDDNKRPSGIPERISGSSSGTTATLTIRDVRAEDEGDYYCFS
  GYVDSDSKLYVFGSGTQLTVL
  [spacer (SEQ ID NO: 918)][J43 MP003 2001 (SEQ ID NO: 1004)] nucleic acid sequence:
  (SEQ ID NO: 520)
  [CAAGGCCAGTCTGGCCAAGGT][ACGAATATTTGGAGTTGCCAGACTTATTGCGATCATAAGC
  ATAAGGGAGGTGGCTCGAGCGGCGGCTCTATCTCTTCCGGACTGCTGTCCGGCAGATCCGACAA
  TCACGGCGGAGGCTCTTATGAGCTGACTCAGCCACCTTCAGCATCAGTCAATGTAGGAGAGACT
  GTCAAAATCACCTGCTCTGGGGACCAATTGCCGAAATATTTTGCAGATTGGTTTCATCAAAGGT
  CAGACCAGACCATTTTGCAAGTGATATATGATGATAATAAGCGCCCCTCGGGTATCCCTGAAAG
  AATCTCTGGGTCCAGCTCAGGGACAACAGCCACCTTGACCATCAGAGATGTCCGGGCTGAGGAT
  GAAGGTGACTATTACTGTTTCTCAGGATATGTTGATAGTGATAGCAAATTGTATGTTTTTGGCA
  GCGGAACCCAGCTCACCGTCCTA
  [spacer (SEQ ID NO: 362)][J43 MP004 2001 (SEQ ID NO: 1005)] amino acid sequence:
  (SEQ ID NO: 521)
  [QGQSGQG][SDHKCKLQNCMNTKVGGGSSGGSISSGLLSGRSDNHGGGSYELTQPPSASVNVG
  ETVKITCSGDQLPKYFADWFHQRSDQTILQVIYDDNKRPSGIPERISGSSSGTTATLTIRDVRA
  EDEGDYYCFSGYVDSDSKLYVFGSGTQLTVL]
  J43 MP004 2001 amino acid sequence:
  (SEQ ID NO: 1080)
  SDHKCKLQNCMNTKVGGGSSGGSISSGLLSGRSDNHGGGSYELTQPPSASVNVGETVKITCSGD
  QLPKYFADWFHQRSDQTILQVIYDDNKRPSGIPERISGSSSGTTATLTIRDVRAEDEGDYYCFS
  GYVDSDSKLYVFGSGTQLTVL
  [spacer (SEQ ID NO: 918)][J43 MP004 2001 (SEQ ID NO: 1006)] nucleic acid sequence:
  (SEQ ID NO: 522)
  [CAAGGCCAGTCTGGCCAAGGT][AGTGATCATAAGTGCAAGCTTCAGAATTGCATGAATACTA
  AGGTTGGAGGTGGCTCGAGCGGCGGCTCTATCTCTTCCGGACTGCTGTCCGGCAGATCCGACAA
  TCACGGCGGAGGCTCTTATGAGCTGACTCAGCCACCTTCAGCATCAGTCAATGTAGGAGAGACT
  GTCAAAATCACCTGCTCTGGGGACCAATTGCCGAAATATTTTGCAGATTGGTTTCATCAAAGGT
  CAGACCAGACCATTTTGCAAGTGATATATGATGATAATAAGCGCCCCTCGGGTATCCCTGAAAG
  AATCTCTGGGTCCAGCTCAGGGACAACAGCCACCTTGACCATCAGAGATGTCCGGGCTGAGGAT
  GAAGGTGACTATTACTGTTTCTCAGGATATGTTGATAGTGATAGCAAATTGTATGTTTTTGGCA
  GCGGAACCCAGCTCACCGTCCTA
  [spacer (SEQ ID NO: 362)][J43 MP005 2001 (SEQ ID NO: 1007)] amino acid sequence:
  (SEQ ID NO: 523)
  [QGQSGQG][PGNCHPMQKEMCQFIGGGSSGGSISSGLLSGRSDNHGGGSYELTQPPSASVNVG
  ETVKITCSGDQLPKYFADWFHQRSDQTILQVIYDDNKRPSGIPERISGSSSGTTATLTIRDVRA
  EDEGDYYCFSGYVDSDSKLYVFGSGTQLTVL]
  J43 MP005 2001 amino acid sequence:
  (SEQ ID NO: 1081)
  PGNCHPMQKEMCQFIGGGSSGGSISSGLLSGRSDNHGGGSYELTQPPSASVNVGETVKITCSGD
  QLPKYFADWFHQRSDQTILQVIYDDNKRPSGIPERISGSSSGTTATLTIRDVRAEDEGDYYCFS
  GYVDSDSKLYVFGSGTQLTVL
  [spacer (SEQ ID NO: 918)][J43 MP005 2001 (SEQ ID NO: 1008)] nucleic acid sequence:
  (SEQ ID NO: 524)
  [CAAGGCCAGTCTGGCCAAGGT][CCTGGTAATTGCCATCCTATGCAGAAGGAGATGTGCCAGT
  TTATTGGAGGTGGCTCGAGCGGCGGCTCTATCTCTTCCGGACTGCTGTCCGGCAGATCCGACAA
  TCACGGCGGAGGCTCTTATGAGCTGACTCAGCCACCTTCAGCATCAGTCAATGTAGGAGAGACT
  GTCAAAATCACCTGCTCTGGGGACCAATTGCCGAAATATTTTGCAGATTGGTTTCATCAAAGGT
  CAGACCAGACCATTTTGCAAGTGATATATGATGATAATAAGCGCCCCTCGGGTATCCCTGAAAG
  AATCTCTGGGTCCAGCTCAGGGACAACAGCCACCTTGACCATCAGAGATGTCCGGGCTGAGGAT
  GAAGGTGACTATTACTGTTTCTCAGGATATGTTGATAGTGATAGCAAATTGTATGTTTTTGGCA
  GCGGAACCCAGCTCACCGTCCTA
  [spacer (SEQ ID NO: 362)][J43 MP006 2001 (SEQ ID NO: 1009)] amino acid sequence:
  (SEQ ID NO: 525)
  [QGQSGQG][VEHLCYTHNKCKHPDGGGSSGGSISSGLLSGRSDNHGGGSYELTQPPSASVNVG
  ETVKITCSGDQLPKYFADWFHQRSDQTILQVIYDDNKRPSGIPERISGSSSGTTATLTIRDVRA
  EDEGDYYCFSGYVDSDSKLYVFGSGTQLTVL]
  J43 MP006 2001 amino acid sequence:
  (SEQ ID NO: 1082)
  VEHLCYTHNKCKHPDGGGSSGGSISSGLLSGRSDNHGGGSYELTQPPSASVNVGETVKITCSGD
  QLPKYFADWFHQRSDQTILQVIYDDNKRPSGIPERISGSSSGTTATLTIRDVRAEDEGDYYCFS
  GYVDSDSKLYVFGSGTQLTVL
  [spacer (SEQ ID NO: 918)][J43 MP006 2001 (SEQ ID NO: 1010)] nucleic acid sequence:
  (SEQ ID NO: 526)
  [CAAGGCCAGTCTGGCCAAGGT][GTTGAGCATTTGTGCTATACGCATAATAAGTGCAAGCATC
  CTGATGGAGGTGGCTCGAGCGGCGGCTCTATCTCTTCCGGACTGCTGTCCGGCAGATCCGACAA
  TCACGGCGGAGGCTCTTATGAGCTGACTCAGCCACCTTCAGCATCAGTCAATGTAGGAGAGACT
  GTCAAAATCACCTGCTCTGGGGACCAATTGCCGAAATATTTTGCAGATTGGTTTCATCAAAGGT
  CAGACCAGACCATTTTGCAAGTGATATATGATGATAATAAGCGCCCCTCGGGTATCCCTGAAAG
  AATCTCTGGGTCCAGCTCAGGGACAACAGCCACCTTGACCATCAGAGATGTCCGGGCTGAGGAT
  GAAGGTGACTATTACTGTTTCTCAGGATATGTTGATAGTGATAGCAAATTGTATGTTTTTGGCA
  GCGGAACCCAGCTCACCGTCCTA
  [spacer (SEQ ID NO: 362)][J43 MP007 2001 (SEQ ID NO: 1011)] amino acid sequence:
  (SEQ ID NO: 527)
  [QGQSGQG][TIPRCGQHPKCKDTLGGGSSGGSISSGLLSGRSDNHGGGSYELTQPPSASVNVG
  ETVKITCSGDQLPKYFADWFHQRSDQTILQVIYDDNKRPSGIPERISGSSSGTTATLTIRDVRA
  EDEGDYYCFSGYVDSDSKLYVFGSGTQLTVL]
  J43 MP007 2001 amino acid sequence:
  (SEQ ID NO: 1083)
  TIPRCGQHPKCKDTLGGGSSGGSISSGLLSGRSDNHGGGSYELTQPPSASVNVGETVKITCSGD
  QLPKYFADWFHQRSDQTILQVIYDDNKRPSGIPERISGSSSGTTATLTIRDVRAEDEGDYYCFS
  GYVDSDSKLYVFGSGTQLTVL
  [spacer (SEQ ID NO: 918)][J43 MP007 2001 (SEQ ID NO: 1012)] nucleic acid sequence:
  (SEQ ID NO: 528)
  [CAAGGCCAGTCTGGCCAAGGT][ACTATTCCGAGGTGCGGTCAGCATCCGAAGTGCAAGGATA
  CTTTGGGAGGTGGCTCGAGCGGCGGCTCTATCTCTTCCGGACTGCTGTCCGGCAGATCCGACAA
  TCACGGCGGAGGCTCTTATGAGCTGACTCAGCCACCTTCAGCATCAGTCAATGTAGGAGAGACT
  GTCAAAATCACCTGCTCTGGGGACCAATTGCCGAAATATTTTGCAGATTGGTTTCATCAAAGGT
  CAGACCAGACCATTTTGCAAGTGATATATGATGATAATAAGCGCCCCTCGGGTATCCCTGAAAG
  AATCTCTGGGTCCAGCTCAGGGACAACAGCCACCTTGACCATCAGAGATGTCCGGGCTGAGGAT
  GAAGGTGACTATTACTGTTTCTCAGGATATGTTGATAGTGATAGCAAATTGTATGTTTTTGGCA
  GCGGAACCCAGCTCACCGTCCTA
  [spacer (SEQ ID NO: 362)][J43 MP008 2001 (SEQ ID NO: 1013)] amino acid sequence:
  (SEQ ID NO: 529)
  [QGQSGQG][ACRICQDHPKTKWNSGGGSSGGSISSGLLSGRSDNHGGGSYELTQPPSASVNVG
  ETVKITCSGDQLPKYFADWFHQRSDQTILQVIYDDNKRPSGIPERISGSSSGTTATLTIRDVRA
  EDEGDYYCFSGYVDSDSKLYVFGSGTQLTVL]
  J43 MP008 2001 amino acid sequence:
  (SEQ ID NO: 1084)
  ACRICQDHPKTKWNSGGGSSGGSISSGLLSGRSDNHGGGSYELTQPPSASVNVGETVKITCSGD
  QLPKYFADWFHQRSDQTILQVIYDDNKRPSGIPERISGSSSGTTATLTIRDVRAEDEGDYYCFS
  GYVDSDSKLYVFGSGTQLTVL
  [spacer (SEQ ID NO: 918)][J43 MP008 2001 (SEQ ID NO: 1014)] nucleic acid sequence:
  (SEQ ID NO: 530)
  [CAAGGCCAGTCTGGCCAAGGT][GCGTGCCGTATTTGTCAGGATCATCCTAAGACGAAGTGGA
  ATTCTGGAGGTGGCTCGAGCGGCGGCTCTATCTCTTCCGGACTGCTGTCCGGCAGATCCGACAA
  TCACGGCGGAGGCTCTTATGAGCTGACTCAGCCACCTTCAGCATCAGTCAATGTAGGAGAGACT
  GTCAAAATCACCTGCTCTGGGGACCAATTGCCGAAATATTTTGCAGATTGGTTTCATCAAAGGT
  CAGACCAGACCATTTTGCAAGTGATATATGATGATAATAAGCGCCCCTCGGGTATCCCTGAAAG
  AATCTCTGGGTCCAGCTCAGGGACAACAGCCACCTTGACCATCAGAGATGTCCGGGCTGAGGAT
  GAAGGTGACTATTACTGTTTCTCAGGATATGTTGATAGTGATAGCAAATTGTATGTTTTTGGCA
  GCGGAACCCAGCTCACCGTCCTA
  [spacer (SEQ ID NO: 362)][J43 MP009 2001 (SEQ ID NO: 1015)] amino acid sequence:
  (SEQ ID NO: 531)
  [QGQSGQG][LIQCTGNLDHKCKHYGGGSSGGSISSGLLSGRSDNHGGGSYELTQPPSASVNVG
  ETVKITCSGDQLPKYFADWFHQRSDQTILQVIYDDNKRPSGIPERISGSSSGTTATLTIRDVRA
  EDEGDYYCFSGYVDSDSKLYVFGSGTQLTVL]
  J43 MP009 2001 amino acid sequence:
  (SEQ ID NO: 1085)
  LIQCTGNLDHKCKHYGGGSSGGSISSGLLSGRSDNHGGGSYELTQPPSASVNVGETVKITCSGD
  QLPKYFADWFHQRSDQTILQVIYDDNKRPSGIPERISGSSSGTTATLTIRDVRAEDEGDYYCFS
  GYVDSDSKLYVFGSGTQLTVL
  [spacer (SEQ ID NO: 918)][J43 MP009 2001 (SEQ ID NO: 1016)] nucleic acid sequence:
  (SEQ ID NO: 532)
  [CAAGGCCAGTCTGGCCAAGGT][CTTATTCAGTGCACTGGTAATCTTGATCATAAGTGCAAGC
  ATTATGGAGGTGGCTCGAGCGGCGGCTCTATCTCTTCCGGACTGCTGTCCGGCAGATCCGACAA
  TCACGGCGGAGGCTCTTATGAGCTGACTCAGCCACCTTCAGCATCAGTCAATGTAGGAGAGACT
  GTCAAAATCACCTGCTCTGGGGACCAATTGCCGAAATATTTTGCAGATTGGTTTCATCAAAGGT
  CAGACCAGACCATTTTGCAAGTGATATATGATGATAATAAGCGCCCCTCGGGTATCCCTGAAAG
  AATCTCTGGGTCCAGCTCAGGGACAACAGCCACCTTGACCATCAGAGATGTCCGGGCTGAGGAT
  GAAGGTGACTATTACTGTTTCTCAGGATATGTTGATAGTGATAGCAAATTGTATGTTTTTGGCA
  GCGGAACCCAGCTCACCGTCCT
  [spacer (SEQ ID NO: 362)][J43 MP010 2001 (SEQ ID NO: 1017)] amino acid sequence:
  (SEQ ID NO: 533)
  [QGQSGQG][IPCHHSADHKHKCTSGGGSSGGSISSGLLSGRSDNHGGGSYELTQPPSASVNVG
  ETVKITCSGDQLPKYFADWFHQRSDQTILQVIYDDNKRPSGIPERISGSSSGTTATLTIRDVRA
  EDEGDYYCFSGYVDSDSKLYVFGSGTQLTVL]
  J43 MP010 2001 amino acid sequence:
  (SEQ ID NO: 1086)
  IPCHHSADHKHKCTSGGGSSGGSISSGLLSGRSDNHGGGSYELTQPPSASVNVGETVKITCSGD
  QLPKYFADWFHQRSDQTILQVIYDDNKRPSGIPERISGSSSGTTATLTIRDVRAEDEGDYYCFS
  GYVDSDSKLYVFGSGTQLTVL
  [spacer (SEQ ID NO: 918)][J43 MP010 2001 (SEQ ID NO: 1018)] nucleic acid sequence:
  (SEQ ID NO: 534)
  [CAAGGCCAGTCTGGCCAAGGT][ATTCCTTGCCATCATAGTGCTGATCATAAGCATAAGTGCA
  CGAGTGGAGGTGGCTCGAGCGGCGGCTCTATCTCTTCCGGACTGCTGTCCGGCAGATCCGACAA
  TCACGGCGGAGGCTCTTATGAGCTGACTCAGCCACCTTCAGCATCAGTCAATGTAGGAGAGACT
  GTCAAAATCACCTGCTCTGGGGACCAATTGCCGAAATATTTTGCAGATTGGTTTCATCAAAGGT
  CAGACCAGACCATTTTGCAAGTGATATATGATGATAATAAGCGCCCCTCGGGTATCCCTGAAAG
  AATCTCTGGGTCCAGCTCAGGGACAACAGCCACCTTGACCATCAGAGATGTCCGGGCTGAGGAT
  GAAGGTGACTATTACTGTTTCTCAGGATATGTTGATAGTGATAGCAAATTGTATGTTTTTGGCA
  GCGGAACCCAGCTCACCGTCCTA
  [spacer (SEQ ID NO: 362)][J43 MP011 2001 (SEQ ID NO: 1019)] amino acid sequence:
  (SEQ ID NO: 535)
  [QGQSGQG][SRQICADYNCHNKYKGGGSSGGSISSGLLSGRSDNHGGGSYELTQPPSASVNVG
  ETVKITCSGDQLPKYFADWFHQRSDQTILQVIYDDNKRPSGIPERISGSSSGTTATLTIRDVRA
  EDEGDYYCFSGYVDSDSKLYVFGSGTQLTVL]
  J43 MP011 2001 amino acid sequence:
  (SEQ ID NO: 1087)
  SRQICADYNCHNKYKGGGSSGGSISSGLLSGRSDNHGGGSYELTQPPSASVNVGETVKITCSGD
  QLPKYFADWFHQRSDQTILQVIYDDNKRPSGIPERISGSSSGTTATLTIRDVRAEDEGDYYCFS
  GYVDSDSKLYVFGSGTQLTVL
  [spacer (SEQ ID NO: 918)][J43 MP011 2001 (SEQ ID NO: 1020)] nucleic acid sequence:
  (SEQ ID NO: 536)
  [CAAGGCCAGTCTGGCCAAGGT][TCGCGGCAGATTTGCGCTGATTATAATTGCCATAATAAGT
  ATAAGGGAGGTGGCTCGAGCGGCGGCTCTATCTCTTCCGGACTGCTGTCCGGCAGATCCGACAA
  TCACGGCGGAGGCTCTTATGAGCTGACTCAGCCACCTTCAGCATCAGTCAATGTAGGAGAGACT
  GTCAAAATCACCTGCTCTGGGGACCAATTGCCGAAATATTTTGCAGATTGGTTTCATCAAAGGT
  CAGACCAGACCATTTTGCAAGTGATATATGATGATAATAAGCGCCCCTCGGGTATCCCTGAAAG
  AATCTCTGGGTCCAGCTCAGGGACAACAGCCACCTTGACCATCAGAGATGTCCGGGCTGAGGAT
  GAAGGTGACTATTACTGTTTCTCAGGATATGTTGATAGTGATAGCAAATTGTATGTTTTTGGCA
  GCGGAACCCAGCTCACCGTCCTA
  [spacer (SEQ ID NO: 362)][J43 MP012 2001 (SEQ ID NO: 1021)] amino acid sequence:
  (SEQ ID NO: 537)
  [QGQSGQG][QPCNPQIDHKIKCIYGGGSSGGSISSGLLSGRSDNHGGGSYELTQPPSASVNVG
  ETVKITCSGDQLPKYFADWFHQRSDQTILQVIYDDNKRPSGIPERISGSSSGTTATLTIRDVRA
  EDEGDYYCFSGYVDSDSKLYVFGSGTQLTVL
  J43 MP012 2001 amino acid sequence:
  (SEQ ID NO: 1088)
  QPCNPQIDHKIKCIYGGGSSGGSISSGLLSGRSDNHGGGSYELTQPPSASVNVGETVKITCSGD
  QLPKYFADWFHQRSDQTILQVIYDDNKRPSGIPERISGSSSGTTATLTIRDVRAEDEGDYYCFS
  GYVDSDSKLYVFGSGTQLTVL
  [spacer (SEQ ID NO: 918)][J43 MP012 2001 (SEQ ID NO: 1022)] nucleic acid sequence:
  (SEQ ID NO: 538)
  [CAAGGCCAGTCTGGCCAAGGT][CAGCCTTGCAATCCGCAGATTGATCATAAGATTAAGTGCA
  TTTATGGAGGTGGCTCGAGCGGCGGCTCTATCTCTTCCGGACTGCTGTCCGGCAGATCCGACAA
  TCACGGCGGAGGCTCTTATGAGCTGACTCAGCCACCTTCAGCATCAGTCAATGTAGGAGAGACT
  GTCAAAATCACCTGCTCTGGGGACCAATTGCCGAAATATTTTGCAGATTGGTTTCATCAAAGGT
  CAGACCAGACCATTTTGCAAGTGATATATGATGATAATAAGCGCCCCTCGGGTATCCCTGAAAG
  AATCTCTGGGTCCAGCTCAGGGACAACAGCCACCTTGACCATCAGAGATGTCCGGGCTGAGGAT
  GAAGGTGACTATTACTGTTTCTCAGGATATGTTGATAGTGATAGCAAATTGTATGTTTTTGGCA
  GCGGAACCCAGCTCACCGTCCTA
  [spacer (SEQ ID NO: 362)][J43 MP013 2001 (SEQ ID NO: 1023)] amino acid sequence:
  (SEQ ID NO: 539)
  [QGQSGQG][HYTICMTHNKCKDMAGGGSSGGSISSGLLSGRSDNHGGGSYELTQPPSASVNVG
  ETVKITCSGDQLPKYFADWFHQRSDQTILQVIYDDNKRPSGIPERISGSSSGTTATLTIRDVRA
  EDEGDYYCFSGYVDSDSKLYVFGSGTQLTVL]
  J43 MP013 2001 amino acid sequence:
  (SEQ ID NO: 1089)
  HYTICMTHNKCKDMAGGGSSGGSISSGLLSGRSDNHGGGSYELTQPPSASVNVGETVKITCSGD
  QLPKYFADWFHQRSDQTILQVIYDDNKRPSGIPERISGSSSGTTATLTIRDVRAEDEGDYYCFS
  GYVDSDSKLYVFGSGTQLTVL
  [spacer (SEQ ID NO: 918)][J43 MP013 2001 (SEQ ID NO: 1024)] nucleic acid sequence:
  (SEQ ID NO: 540)
  [CAAGGCCAGTCTGGCCAAGGT][CATTATACTATTTGCATGACGCATAATAAGTGCAAGGATA
  TGGCGGGAGGTGGCTCGAGCGGCGGCTCTATCTCTTCCGGACTGCTGTCCGGCAGATCCGACAA
  TCACGGCGGAGGCTCTTATGAGCTGACTCAGCCACCTTCAGCATCAGTCAATGTAGGAGAGACT
  GTCAAAATCACCTGCTCTGGGGACCAATTGCCGAAATATTTTGCAGATTGGTTTCATCAAAGGT
  CAGACCAGACCATTTTGCAAGTGATATATGATGATAATAAGCGCCCCTCGGGTATCCCTGAAAG
  AATCTCTGGGTCCAGCTCAGGGACAACAGCCACCTTGACCATCAGAGATGTCCGGGCTGAGGAT
  GAAGGTGACTATTACTGTTTCTCAGGATATGTTGATAGTGATAGCAAATTGTATGTTTTTGGCA
  GCGGAACCCAGCTCACCGTCCTA
  [spacer (SEQ ID NO: 362)][J43 MP014 2001 (SEQ ID NO: 1025)] amino acid sequence:
  (SEQ ID NO: 541)
  [QGQSGQG[]ANSCLAVEHKCKHNYGGGSSGGSISSGLLSGRSDNHGGGSYELTQPPSASVNVG
  ETVKITCSGDQLPKYFADWFHQRSDQTILQVIYDDNKRPSGIPERISGSSSGTTATLTIRDVRA
  EDEGDYYCFSGYVDSDSKLYVFGSGTQLTVL]
  J43 MP014 2001 amino acid sequence:
  (SEQ ID NO: 1090)
  ANSCLAVEHKCKHNYGGGSSGGSISSGLLSGRSDNHGGGSYELTQPPSASVNVGETVKITCSGD
  QLPKYFADWFHQRSDQTILQVIYDDNKRPSGIPERISGSSSGTTATLTIRDVRAEDEGDYYCFS
  GYVDSDSKLYVFGSGTQLTVL
  [spacer (SEQ ID NO: 918)][J43 MP014 2001 (SEQ ID NO: 1026)] nucleic acid sequence:
  (SEQ ID NO: 542)
  [CAAGGCCAGTCTGGCCAAGGT][GCTAATAGTTGCCTTGCTGTTGAGCATAAGTGCAAGCATA
  ATTATGGAGGTGGCTCGAGCGGCGGCTCTATCTCTTCCGGACTGCTGTCCGGCAGATCCGACAA
  TCACGGCGGAGGCTCTTATGAGCTGACTCAGCCACCTTCAGCATCAGTCAATGTAGGAGAGACT
  GTCAAAATCACCTGCTCTGGGGACCAATTGCCGAAATATTTTGCAGATTGGTTTCATCAAAGGT
  CAGACCAGACCATTTTGCAAGTGATATATGATGATAATAAGCGCCCCTCGGGTATCCCTGAAAG
  AATCTCTGGGTCCAGCTCAGGGACAACAGCCACCTTGACCATCAGAGATGTCCGGGCTGAGGAT
  GAAGGTGACTATTACTGTTTCTCAGGATATGTTGATAGTGATAGCAAATTGTATGTTTTTGGCA
  GCGGAACCCAGCTCACCGTCCTA

Reformatted Anti-Mouse PD-1 Heavy and Light Chains:

• J43v2 light chain (LC) amino acid sequence:

  (SEQ ID NO: 543)

  YELTQPPSASVNVGETVKITCSGDQLPKYFADWFHQRSDQTILQVIYDDN

  KRPSGIPERISGSSSGTTATLTIRDVRAEDEGDYYCFSGYVDSDSKLYVF

  GSGTQLTVLGGPKSSPKVTVFPPSPEELRTNKATLVCLVNDFYPGSATVT

  WKANGATINDGVKTTKPSKQGQNYMTSSYLSLTADQWKSHNRVSCQVTHE

  GETVEKSLSPAECL

  J43v2 LC nucleotide sequence 1:

  (SEQ ID NO: 544)

  TATGAGCTGACTCAGCCACCTTCAGCATCAGTCAATGTAGGAGAGACTGT

  CAAAATCACCTGCTCTGGGGACCAATTGCCGAAATATTTTGCAGATTGGT

  TTCATCAAAGGTCAGACCAGACCATTTTGCAAGTGATATATGATGATAAT

  AAGCGCCCCTCGGGTATCCCTGAAAGAATCTCTGGGTCCAGCTCAGGGAC

  AACAGCCACCTTGACCATCAGAGATGTCCGGGCTGAGGATGAAGGTGACT

  ATTACTGTTTCTCAGGATATGTTGATAGTGATAGCAAATTGTATGTTTTT

  GGCAGCGGAACCCAGCTCACCGTCCTAGGTGGACCCAAGTCTTCTCCCAA

  AGTCACAGTGTTTCCACCTTCACCTGAGGAGCTCCGGACAAACAAAGCCA

  CACTGGTGTGTCTGGTTAATGACTTCTACCCGGGTTCTGCAACAGTGACC

  TGGAAGGCAAATGGAGCAACTATCAATGATGGGGTGAAGACTACAAAGCC

  TTCCAAACAGGGCCAAAACTACATGACCAGCAGCTACCTAAGTTTGACAG

  CAGACCAGTGGAAATCTCACAACAGGGTTTCCTGCCAAGTTACCCATGAA

  GGGGAAACTGTGGAGAAGAGTTTGTCCCCTGCAGAATGTCTT

  J43v2 LC nucleotide sequence 2:

  (SEQ ID NO: 545)

  TACGAGCTGACCCAGCCTCCTAGCGCCTCCGTGAATGTGGGCGAGACAGT

  GAAGATCACCTGTAGCGGCGACCAGCTGCCCAAGTACTTCGCCGACTGGT

  TCCACCAGCGGAGCGACCAGACAATCCTGCAAGTGATCTACGACGACAAC

  AAGCGGCCCAGCGGCATCCCCGAGAGAATCAGCGGAAGCAGCAGCGGCAC

  CACCGCCACCCTGACCATTAGAGATGTGCGGGCCGAGGACGAGGGCGACT

  ACTACTGCTTTAGCGGCTACGTGGACAGCGACAGCAAGCTGTACGTGTTC

  GGCTCCGGTACCCAGCTGACAGTGCTGGGCGGACCTAAGAGCAGCCCCAA

  AGTGACCGTGTTCCCCCCAAGCCCCGAGGAACTGAGGACCAACAAGGCCA

  CCCTCGTGTGCCTCGTGAACGACTTCTACCCTGGCAGCGCCACCGTGACC

  TGGAAAGCCAATGGCGCCACCATCAACGACGGCGTGAAAACCACCAAGCC

  CAGCAAGCAGGGCCAGAACTACATGACCAGCAGCTACCTGAGCCTGACCG

  CCGACCAGTGGAAGTCCCACAACAGAGTGTCCTGCCAAGTGACCCACGAG

  GGGGAAACCGTGGAAAAGAGCCTGAGCCCTGCCGAGTGCCTG

  J43v2 mIgG2a heavy chain (HC) amino acid sequence:

  (SEQ ID NO: 546)

  EVRLLESGGGLVKPEGSLKLSCVASGFTFSDYFMSWVRQAPGKGLEWVAH

  IYTKSYNYATYYSGSVKGRFTISRDDSRSMVYLQMNNLRTEDTATYYCTR

  DGSGYPSLDFWGQGTQVTVSSAKTTAPSVYPLAPVCGDTTGSSVTLGCLV

  KGYFPEPVTLTWNSGSLSSGVHTFPAVLQSDLYTLSSSVTVTSSTWPSQS

  ITCNVAHPASSTKVDKKIEPRGPTIKPCPPCKCPAPNLLGGPSVFIFPPK

  IKDVLMISLSPIVTCVVVDVSEDDPDVQISWFVNNVEVHTAQTQTHREDY

  NSTLRVVSALPIQHQDWMSGKEFKCKVNNKDLPAPIERTISKPKGSVRAP

  QVYVLPPPEEEMTKKQVILTCMVTDPMPEDIYVEWINNGKTELNYKNTEP

  VLDSDGSYFMYSKLRVEKKNWVERNSYSCSVVHEGLHNHHTTKSFSRTPG

  K

  J43v2 mIgG2a HC nucleic acid sequence:

  (SEQ ID NO: 547)

  GAGGTGCGGCTTCTGGAGTCTGGTGGAGGATTAGTGAAGCCTGAGGGGTC

  ACTGAAACTCTCCTGTGTGGCCTCTGGATTCACCTTCAGTGACTATTTCA

  TGAGCTGGGTCCGCCAGGCTCCAGGGAAGGGGCTGGAGTGGGTTGCTCAC

  ATATACACGAAAAGTTATAATTATGCAACTTATTACTCGGGTTCGGTGAA

  AGGCAGATTCACCATCTCCAGAGATGATTCCCGAAGCATGGTCTACCTGC

  AAATGAACAACCTGAGAACTGAGGACACGGCCACTTATTACTGTACAAGA

  GATGGAAGCGGATATCCCTCTCTGGATTTCTGGGGTCAAGGGACCCAAGT

  CACTGTCTCCTCAGCTAAAACAACAGCCCCATCGGTCTATCCACTGGCCC

  CTGTGTGTGGAGATACAACTGGCTCCTCGGTGACTCTAGGATGCCTGGTC

  AAGGGTTATTTCCCTGAGCCAGTGACCTTGACCTGGAACTCTGGATCCCT

  GTCCAGTGGTGTGCACACCTTCCCAGCTGTCCTGCAGTCTGACCTCTACA

  CCCTCAGCAGCTCAGTGACTGTAACCTCGAGCACCTGGCCCAGCCAGTCC

  ATCACCTGCAATGTGGCCCACCCGGCAAGCAGCACCAAGGTGGACAAGAA

  AATTGAGCCCAGAGGGCCCACAATCAAGCCCTGTCCTCCATGCAAATGCC

  CAGCACCTAACCTCTTGGGTGGACCATCCGTCTTCATCTTCCCTCCAAAG

  ATCAAGGATGTACTCATGATCTCCCTGAGCCCCATAGTCACATGTGTGGT

  GGTGGATGTGAGCGAGGATGACCCAGATGTCCAGATCAGCTGGTTTGTGA

  ACAACGTGGAAGTACACACAGCTCAGACACAAACCCATAGAGAGGATTAC

  AACAGTACTCTCCGGGTGGTCAGTGCCCTCCCCATCCAGCACCAGGACTG

  GATGAGTGGCAAGGAGTTCAAATGCAAGGTCAACAACAAAGACCTCCCAG

  CGCCCATCGAGAGAACCATCTCAAAACCCAAAGGGTCAGTAAGAGCTCCA

  CAGGTATATGTCTTGCCTCCACCAGAAGAAGAGATGACTAAGAAACAGGT

  CACTCTGACCTGCATGGTCACAGACTTCATGCCTGAAGACATTTACGTGG

  AGTGGACCAACAACGGGAAAACAGAGCTAAACTACAAGAACACTGAACCA

  GTCCTGGACTCTGATGGTTCTTACTTCATGTACAGCAAGCTGAGAGTGGA

  AAAGAAGAACTGGGTGGAAAGAAATAGCTACTCCTGTTCAGTGGTCCACG

  AGGGTCTGCACAATCACCACACGACTAAGAGCTTCTCCCGGACTCCGGGT

  AAA

Example 16: Activatable Anti-mPD-1 Antibodies with a Range of Masking Efficiencies
• This example describes the modulation of anti-mPD-1 antibody masking efficiencies by masking moiety truncation and single amino-acid substitution.
• Four J43 activatable antibodies were selected to generate families of activatable anti-mPD-1 antibodies by masking moiety truncation or amino acid substitution of one or more MM residues. Table 18 lists the designed MMs. Activatable J43v2 antibodies with the designed MM and 2001 substrate were produced by transfection of 30 mL HEK293 cells and selected activatable antibodies (sequences MPtrunc ELISA activatable antibody LCs) were evaluated for masking by ELISA as described in Example 15 (FIG. 23).
• In some embodiments, the activatable antibody also includes a spacer sequence. In some embodiments, the spacer is joined directly to the MM of the activatable antibody. In some embodiments, the spacer is joined directly to the MM of the activatable antibody in the structural arrangement from N-terminus to C-terminus of spacer-MM-CM-AB. In some embodiments, the spacer joined directly to the N-terminus of MM of the activatable antibody is selected from the group consisting of QGQSGQG (SEQ ID NO: 362), QGQSGQ (SEQ ID NO: 913), QGQSG (SEQ ID NO: 914), QGQS (SEQ ID NO: 915), QGQ (SEQ ID NO: 916), QG (SEQ ID NO: 917), and Q. In some embodiments, the spacer includes at least the amino acid sequence QGQSGQG (SEQ ID NO: 362). In some embodiments, the spacer includes at least the amino acid sequence QGQSGQ (SEQ ID NO: 913). In some embodiments, the spacer includes at least the amino acid sequence QGQSG (SEQ ID NO: 914). In some embodiments, the spacer includes at least the amino acid sequence QGQS (SEQ ID NO: 915). In some embodiments, the spacer includes at least the amino acid sequence QGQ (SEQ ID NO: 916). In some embodiments, the spacer includes at least the amino acid sequence QG (SEQ ID NO: 917). In some embodiments, the spacer includes at least the amino acid residue Q. In some embodiments, the activatable antibody does not include a spacer sequence.
• While the sequences shown below include the spacer sequence of SEQ ID NO: 362, those of ordinary skill in the art appreciate that the activatable anti-PD-1 antibodies of the disclosure can include any suitable spacer sequence, such as, for example, a spacer sequence selected from the group consisting of QGQSGQG (SEQ ID NO: 362), QGQSGQ (SEQ ID NO: 913), QGQSG (SEQ ID NO: 914), QGQS (SEQ ID NO: 915), QGQ (SEQ ID NO: 916), QG (SEQ ID NO: 917), and Q. While the sequences shown below include the spacer sequence of SEQ ID NO: 362, those of ordinary skill in the art will also appreciate that activatable anti-PD-1 antibodies of the disclosure in some embodiments do not include a spacer sequence.

• TABLE 18
  Masking moiety sequences

  	Mask	Amino Acid Sequence	SEQ ID NO:
  	MP8-1	QDHPKTKWNS	548
  	MP8-2	ACRICQDHPATKWNS	549
  	MP8-3	ACRICQDHPKTAWNS	550
  	MP8-4	ACRICQDAPKTKWNS	551
  	MP8-5	ACRICQDHAKTKWNS	552
  	MP8-6	DHPATKWNS	553
  	MP8-7	DHPKTAWNS	554
  	MP8-8	DAPKTKWNS	555
  	MP8-9	DAPATKWNS	556
  	MP8-10	ACRICQDHP	557
  	MP7-1	HPQSKDTL	558
  	MP7-2	HPKSQDTL	559
  	MP7-3	TIPRCGQHPLCLDTL	560
  	MP7-4	HPLSLDTL	561
  	MP7-5	HPASKDTL	562
  	MP7-6	HPKSADTL	563
  	MP5-1	PGNCHPLQKELCQFI	564
  	MP5-2	HPLQKELAQFI	565
  	MP5-3	HPLALELAQFI	566
  	MP5-4	PGNCHPLQLELCQFI	567
  	MP3-1	TNIWSCQTYCDHAHA	568
  	MP3-2	TNIWSCQTYCDHAHL	569
  	MP3-3	TNIWSCQTYCDHLHA	570
  	MP3-4	TNIWSCQTYCDHKHA	571

• [Spacer (SEQ ID NO: 362)]

  [J43 MP5-2 2001 (SEQ ID NO: 1027)]

  Amino Acid Sequence:

  (SEQ ID NO: 572)

  [QGQSGQG][HPLQKELAQFIGGGSSGGSISSGLLSGRSDNHGGGSYE

  LTQPPSASVNVGETVKITCSGDQLPKYFADWFHQRSDQTILQVIYDDNK

  RPSGIPERISGSSSGTTATLTIRDVRAEDEGDYYCFSGYVDSDSKLYV

  FGSGTQLTVL]

  J43 MP5-2 2001 Amino Acid Sequence:

  (SEQ ID NO: 1113)

  HPLQKELAQFIGGGSSGGSISSGLLSGRSDNHGGGSYELTQPPSASVNVG

  ETVKITCSGDQLPKYFADWFHQRSDQTILQVIYDDNKRPSGIPERISGSS

  SGTTATLTIRDVRAEDEGDYYCFSGYVDSDSKLYVFGSGTQLTVL

  [Spacer (SEQ ID NO: 918)]

  [J43 MP5-2 2001 (SEQ ID NO: 1038)]

  Nucleic Acid Sequence:

  (SEQ ID NO: 573)

  [CAAGGCCAGTCTGGCCAAGGT][CATCCTCTGCAGAAGGAGCTGGCCCA

  GTTTATTGGAGGTGGCTCGAGCGGCGGCTCTATCTCTTCCGGACTGCTGT

  CCGGCAGATCCGACAATCACGGCGGAGGCTCTTACGAGCTGACCCAGCCT

  CCTAGCGCCTCCGTGAATGTGGGCGAGACAGTGAAGATCACCTGTAGCGG

  CGACCAGCTGCCCAAGTACTTCGCCGACTGGTTCCACCAGCGGAGCGACC

  AGACAATCCTGCAAGTGATCTACGACGACAACAAGCGGCCCAGCGGCATC

  CCCGAGAGAATCAGCGGAAGCAGCAGCGGCACCACCGCCACCCTGACCAT

  TAGAGATGTGCGGGCCGAGGACGAGGGCGACTACTACTGCTTTAGCGGCT

  ACGTGGACAGCGACAGCAAGCTGTACGTGTTCGGCTCCGGTACCCAGCTG

  ACAGTGCTGGGCGGACCTAAGAGCAGCCCCAAAGTGACCGTGTTCCCCCC

  AAGCCCCGAGGAACTGAGGACCAACAAGGCCACCCTCGTGTGCCTCGTGA

  ACGACTTCTACCCTGGCAGCGCCACCGTGACCTGGAAAGCCAATGGCGCC

  ACCATCAACGACGGCGTGAAAACCACCAAGCCCAGCAAGCAGGGCCAGAA

  CTACATGACCAGCAGCTACCTGAGCCTGACCGCCGACCAGTGGAAGTCCC

  ACAACAGAGTGTCCTGCCAAGTGACCCACGAGGGGGAAACCGTGGAAAAG

  AGCCTGAGCCCTGCCGAGTGCCTG

  [Spacer (SEQ ID NO: 362)]

  [J43 MP7-1 2001 (SEQ ID NO: 1039)]

  Amino Acid Sequence:

  (SEQ ID NO: 574)

  [QGQSGQG][HPQSKDTLGGGSSGGSISSGLLSGRSDNHGGGSYELTQPP

  SASVNVGETVKITCSGDQLPKYFADWFHQRSDQTILQVIYDDNKRPSGIP

  ERISGSSSGTTATLTIRDVRAEDEGDYYCFSGYVDSDSKLYVFGSGTQLT

  VL]

  J43 MP7-1 2001 Amino Acid Sequence:

  (SEQ ID NO: 1114)

  HPQSKDTLGGGSSGGSISSGLLSGRSDNHGGGSYELTQPPSASVNVGETV

  KITCSGDQLPKYFADWFHQRSDQTILQVIYDDNKRPSGIPERISGSSSGT

  TATLTIRDVRAEDEGDYYCFSGYVDSDSKLYVFGSGTQLTVL

  [Spacer (SEQ ID NO: 918)]

  [J43 MP7-1 2001 (SEQ ID NO: 2062

  Nucleic Acid Sequence:

  (SEQ ID NO: 575)

  [CAAGGCCAGTCTGGCCAAGGT][CATCCGCAGTCTAAGGATACTTTGGG

  AGGTGGCTCGAGCGGCGGCTCTATCTCTTCCGGACTGCTGTCCGGCAGAT

  CCGACAATCACGGCGGAGGCTCTTACGAGCTGACCCAGCCTCCTAGCGCC

  TCCGTGAATGTGGGCGAGACAGTGAAGATCACCTGTAGCGGCGACCAGCT

  GCCCAAGTACTTCGCCGACTGGTTCCACCAGCGGAGCGACCAGACAATCC

  TGCAAGTGATCTACGACGACAACAAGCGGCCCAGCGGCATCCCCGAGAGA

  ATCAGCGGAAGCAGCAGCGGCACCACCGCCACCCTGACCATTAGAGATGT

  GCGGGCCGAGGACGAGGGCGACTACTACTGCTTTAGCGGCTACGTGGACA

  GCGACAGCAAGCTGTACGTGTTCGGCTCCGGTACCCAGCTGACAGTGCTG

  GGCGGACCTAAGAGCAGCCCCAAAGTGACCGTGTTCCCCCCAAGCCCCGA

  GGAACTGAGGACCAACAAGGCCACCCTCGTGTGCCTCGTGAACGACTTCT

  ACCCTGGCAGCGCCACCGTGACCTGGAAAGCCAATGGCGCCACCATCAAC

  GACGGCGTGAAAACCACCAAGCCCAGCAAGCAGGGCCAGAACTACATGAC

  CAGCAGCTACCTGAGCCTGACCGCCGACCAGTGGAAGTCCCACAACAGAG

  TGTCCTGCCAAGTGACCCACGAGGGGGAAACCGTGGAAAAGAGCCTGAGC

  CCTGCCGAGTGCCTG

MPtrunc ELISA Activatable Antibody LCs:

• [Spacer (SEQ ID NO: 362)]

  [J43 MP7-5 2001 (SEQ ID NO: 1115)]

  Amino Acid Sequence:

  (SEQ ID NO: 576)

  [QGQSGQG][HPASKDTLGGGSSGGSISSGLLSGRSDNHGGGSYELTQPP

  SASVNVGETVKITCSGDQLPKYFADWFHQRSDQTILQVIYDDNKRPSGIP

  ERISGSSSGTTATLTIRDVRAEDEGDYYCFSGYVDSDSKLYVFGSGTQLT

  VL]

  J43 MP7-5 2001 Amino Acid Sequence:

  (SEQ ID NO: 1115)

  HPASKDTLGGGSSGGSISSGLLSGRSDNHGGGSYELTQPPSASVNVGETV

  KITCSGDQLPKYFADWFHQRSDQTILQVIYDDNKRPSGIPERISGSSSGT

  TATLTIRDVRAEDEGDYYCFSGYVDSDSKLYVFGSGTQLTVL

  [Spacer (SEQ ID NO: 918)]

  [J43 MP7-5 2001 (SEQ ID NO: 2061]

  Nucleic Acid Sequence:

  (SEQ ID NO: 577)

  [CAAGGCCAGTCTGGCCAAGGT][CATCCGGCGTCTAAGGATACTTTGGG

  AGGTGGCTCGAGCGGCGGCTCTATCTCTTCCGGACTGCTGTCCGGCAGAT

  CCGACAATCACGGCGGAGGCTCTTACGAGCTGACCCAGCCTCCTAGCGCC

  TCCGTGAATGTGGGCGAGACAGTGAAGATCACCTGTAGCGGCGACCAGCT

  GCCCAAGTACTTCGCCGACTGGTTCCACCAGCGGAGCGACCAGACAATCC

  TGCAAGTGATCTACGACGACAACAAGCGGCCCAGCGGCATCCCCGAGAGA

  ATCAGCGGAAGCAGCAGCGGCACCACCGCCACCCTGACCATTAGAGATGT

  GCGGGCCGAGGACGAGGGCGACTACTACTGCTTTAGCGGCTACGTGGACA

  GCGACAGCAAGCTGTACGTGTTCGGCTCCGGTACCCAGCTGACAGTGCTG

  GGCGGACCTAAGAGCAGCCCCAAAGTGACCGTGTTCCCCCCAAGCCCCGA

  GGAACTGAGGACCAACAAGGCCACCCTCGTGTGCCTCGTGAACGACTTCT

  ACCCTGGCAGCGCCACCGTGACCTGGAAAGCCAATGGCGCCACCATCAAC

  GACGGCGTGAAAACCACCAAGCCCAGCAAGCAGGGCCAGAACTACATGAC

  CAGCAGCTACCTGAGCCTGACCGCCGACCAGTGGAAGTCCCACAACAGAG

  TGTCCTGCCAAGTGACCCACGAGGGGGAAACCGTGGAAAAGAGCCTGAGC

  CCTGCCGAGTGCCTG

  [Spacer (SEQ ID NO: 362)]

  [J43 MP8-2 2001 (SEQ ID NO: 1032)]

  Amino Acid Sequence:

  (SEQ ID NO: 578)

  [QGQSGQG][ACRICQDHPATKWNSGGGSSGGSISSGLLSGRSDNHGGGS

  YELTQPPSASVNVGETVKITCSGDQLPKYFADWFHQRSDQTILQVIYDDN

  KRPSGIPERISGSSSGTTATLTIRDVRAEDEGDYYCFSGYVDSDSKLYVF

  GSGTQLTVL]

  J43 MP8-2 2001 Amino Acid Sequence:

  (SEQ ID NO: 1116)

  ACRICQDHPATKWNSGGGSSGGSISSGLLSGRSDNHGGGSYELTQPPSAS

  VNVGETVKITCSGDQLPKYFADWFHQRSDQTILQVIYDDNKRPSGIPERI

  SGSSSGTTATLTIRDVRAEDEGDYYCFSGYVDSDSKLYVFGSGTQLTVL

  [Spacer (SEQ ID NO: 918)] J43 MP8-2 2001 (SEQ ID

  NO: 1033)] Nucleic Acid Sequence:

  (SEQ ID NO: 579)

  [CAAGGCCAGTCTGGCCAAGGT][GCGTGCCGTATTTGTCAGGATCATCC

  TGCGACGAAGTGGAATTCTGGAGGTGGCTCGAGCGGCGGCTCTATCTCTT

  CCGGACTGCTGTCCGGCAGATCCGACAATCACGGCGGAGGCTCTACGAGC

  TGACCCAGCCTCCTAGCGCCTCCGTGAATGTGGGCGAGACAGTGAAGATC

  ACCTGTAGCGGCGACCAGCTGCCCAAGTACTTCGCCGACTGGTTCCACCA

  GCGGAGCGACCAGACAATCCTGCAAGTGATCTACGACGACAACAAGCGGC

  CCAGCGGCATCCCCGAGAGAATCAGCGGAAGCAGCAGCGGCACCACCGCC

  ACCCTGACCATTAGAGATGTGCGGGCCGAGGACGAGGGCGACTACTACTG

  CTTTAGCGGCTACGTGGACAGCGACAGCAAGCTGTACGTGTTCGGCTCCG

  GTACCCAGCTGACAGTGCTGGGCGGACCTAAGAGCAGCCCCAAAGTGACC

  GTGTTCCCCCCAAGCCCCGAGGAACTGAGGACCAACAAGGCCACCCTCGT

  GTGCCTCGTGAACGACTTCTACCCTGGCAGCGCCACCGTGACCTGGAAAG

  CCAATGGCGCCACCATCAACGACGGCGTGAAAACCACCAAGCCCAGCAAG

  CAGGGCCAGAACTACATGACCAGCAGCTACCTGAGCCTGACCGCCGACCA

  GTGGAAGTCCCACAACAGAGTGTCCTGCCAAGTGACCCACGAGGGGGAAA

  CCGTGGAAAAGAGCCTGAGCCCTGCCGAGTGCCTG

  [Spacer (SEQ ID NO: 362)]

  [J43 MP8-8 2001 (SEQ ID NO: 1034)]

  Amino Acid Sequence:

  (SEQ ID NO: 580)

  [QGQSGQG][DAPKTKWNSGGGSSGGSISSGLLSGRSDNHGGGSYELTQP

  PSASVNVGETVKITCSGDQLPKYFADWFHQRSDQTILQVIYDDNKRPSGI

  PERISGSSSGTTATLTIRDVRAEDEGDYYCFSGYVDSDSKLYVFGSGTQL

  TVL]

  J43 MP8-8 2001 Amino Acid Sequence:

  (SEQ ID NO: 1117)

  DAPKTKWNSGGGSSGGSISSGLLSGRSDNHGGGSYELTQPPSASVNVGET

  VKITCSGDQLPKYFADWFHQRSDQTILQVIYDDNKRPSGIPERISGSSSG

  TTATLTIRDVRAEDEGDYYCFSGYVDSDSKLYVFGSGTQLTVL

  [Spacer (SEQ ID NO: 918)] J43 MP8-8 2001 (SEQ ID

  NO: 1035)] Nucleic Acid Sequence:

  (SEQ ID NO: 581)

  [CAAGGCCAGTCTGGCCAAGGT][GATGCTCCTAAGACGAAGTGGAATTC

  TGGAGGTGGCTCGAGCGGCGGCTCTATCTCTTCCGGACTGCTGTCCGGCA

  GATCCGACAATCACGGCGGAGGCTCTTACGAGCTGACCCAGCCTCCTAGC

  GCCTCCGTGAATGTGGGCGAGACAGTGAAGATCACCTGTAGCGGCGACCA

  GCTGCCCAAGTACTTCGCCGACTGGTTCCACCAGCGGAGCGACCAGACAA

  TCCTGCAAGTGATCTACGACGACAACAAGCGGCCCAGCGGCATCCCCGAG

  AGAATCAGCGGAAGCAGCAGCGGCACCACCGCCACCCTGACCATTAGAGA

  TGTGCGGGCCGAGGACGAGGGCGACTACTACTGCTTTAGCGGCTACGTGG

  ACAGCGACAGCAAGCTGTACGTGTTCGGCTCCGGTACCCAGCTGACAGTG

  CTGGGCGGACCTAAGAGCAGCCCCAAAGTGACCGTGTTCCCCCCAAGCCC

  CGAGGAACTGAGGACCAACAAGGCCACCCTCGTGTGCCTCGTGAACGACT

  TCTACCCTGGCAGCGCCACCGTGACCTGGAAAGCCAATGGCGCCACCATC

  AACGACGGCGTGAAAACCACCAAGCCCAGCAAGCAGGGCCAGAACTACAT

  GACCAGCAGCTACCTGAGCCTGACCGCCGACCAGTGGAAGTCCCACAACA

  GAGTGTCCTGCCAAGTGACCCACGAGGGGGAAACCGTGGAAAAGAGCCTG

  AGCCCTGCCGAGTGCCTG

  [Spacer (SEQ ID NO: 362)]

  [J43 MP8-9 2001 (SEQ ID NO: 1036)]

  Amino Acid Sequence:

  (SEQ ID NO: 582)

  [QGQSGQG][DAPATKWNSGGGSSGGSISSGLLSGRSDNHGGGSYELTQP

  PSASVNVGETVKITCSGDQLPKYFADWFHQRSDQTILQVIYDDNKRPSGI

  PERISGSSSGTTATLTIRDVRAEDEGDYYCFSGYVDSDSKLYVFGSGTQL

  TVL]

  J43 MP8-9 2001 Amino Acid Sequence:

  (SEQ ID NO: 1118)

  DAPATKWNSGGGSSGGSISSGLLSGRSDNHGGGSYELTQPPSASVNVGET

  VKITCSGDQLPKYFADWFHQRSDQTILQVIYDDNKRPSGIPERISGSSSG

  TTATLTIRDVRAEDEGDYYCFSGYVDSDSKLYVFGSGTQLTVL

  [Spacer (SEQ ID NO: 918)]

  [J43 MP8-9 2001 (SEQ ID NO: 1037)]

  Nucleic Acid Sequence:

  (SEQ ID NO: 583)

  [CAAGGCCAGTCTGGCCAAGGT][GATGCTCCTGCGACGAAGTGGAATTC

  TGGAGGTGGCTCGAGCGGCGGCTCTATCTCTTCCGGACTGCTGTCCGGCA

  GATCCGACAATCACGGCGGAGGCTCTTACGAGCTGACCCAGCCTCCTAGC

  GCCTCCGTGAATGTGGGCGAGACAGTGAAGATCACCTGTAGCGGCGACCA

  GCTGCCCAAGTACTTCGCCGACTGGTTCCACCAGCGGAGCGACCAGACAA

  TCCTGCAAGTGATCTACGACGACAACAAGCGGCCCAGCGGCATCCCCGAG

  AGAATCAGCGGAAGCAGCAGCGGCACCACCGCCACCCTGACCATTAGAGA

  TGTGCGGGCCGAGGACGAGGGCGACTACTACTGCTTTAGCGGCTACGTGG

  ACAGCGACAGCAAGCTGTACGTGTTCGGCTCCGGTACCCAGCTGACAGTG

  CTGGGCGGACCTAAGAGCAGCCCCAAAGTGACCGTGTTCCCCCCAAGCCC

  CGAGGAACTGAGGACCAACAAGGCCACCCTCGTGTGCCTCGTGAACGACT

  TCTACCCTGGCAGCGCCACCGTGACCTGGAAAGCCAATGGCGCCACCATC

  AACGACGGCGTGAAAACCACCAAGCCCAGCAAGCAGGGCCAGAACTACAT

  GACCAGCAGCTACCTGAGCCTGACCGCCGACCAGTGGAAGTCCCACAACA

  GAGTGTCCTGCCAAGTGACCCACGAGGGGGAAACCGTGGAAAAGAGCCTG

  AGCCCTGCCGAGTGCCTG

  [Spacer (SEQ ID NO: 362)]

  [J43 MP8-2 2003 (SEQ ID NO: 1119)

  Amino Acid Sequence:

  (SEQ ID NO: 1120)

  [QGQSGQG][ACRICQDHPATKWNSGGGSSGGSISSGLLSGRSANPRGGGS

  YELTQPPSASVNVGETVKITCSGDQLPKYFADWFHQRSDQTILQVIYDDN

  KRPSGIPERISGSSSGTTATLTIRDVRAEDEGDYYCFSGYVDSDSKLYVF

  GSGTQLTVL]

  J43 MP8-2 2003 Amino Acid Sequence:

  (SEQ ID NO: 1119)

  ACRICQDHPATKWNSGGGSSGGSISSGLLSGRSANPRGGGSYELTQPPSA

  SVNVGETVKITCSGDQLPKYFADWFHQRSDQTILQVIYDDNKRPSGIPER

  ISGSSSGTTATLTIRDVRAEDEGDYYCFSGYVDSDSKLYVFGSGTQLTVL

  (SEQ ID NO: 1122)

  [CAAGGCCAGTCTGGCCAAGGT][GCGTGCCGTATTTGTCAGGATCATCC

  TGCGACGAAGTGGAATTCTGGAGGTGGCTCGAGCGGCGGCTCTATCTCTT

  CCGGACTGCTGTCCGGCAGATCCGCCAATCCTCGTGGCGGAGGATCCTAC

  GAGCTGACCCAGCCTCCTAGCGCCTCCGTGAATGTGGGCGAGACAGTGAA

  GATCACCTGTAGCGGCGACCAGCTGCCCAAGTACTTCGCCGACTGGTTCC

  ACCAGCGGAGCGACCAGACAATCCTGCAAGTGATCTACGACGACAACAAG

  CGGCCCAGCGGCATCCCCGAGAGAATCAGCGGAAGCAGCAGCGGCACCAC

  CGCCACCCTGACCATTAGAGATGTGCGGGCCGAGGACGAGGGCGACTACT

  ACTGCTTTAGCGGCTACGTGGACAGCGACAGCAAGCTGTACGTGTTCGGC

  TCCGGTACCCAGCTGACAGTGCTG]

  [Spacer (SEQ ID NO: 362)]

  [J43 MP8-2 2005 (SEQ ID NO: 1123)

  Amino Acid Sequence:

  (SEQ ID NO: 1124)

  [QGQSGQG][ACRICQDHPATKWNSGGGSSGGAVGLLAPPSGRSANPRGG

  GSYELTQPPSASVNVGETVKITCSGDQLPKYFADWFHQRSDQTILQVIYD

  DNKRPSGIPERISGSSSGTTATLTIRDVRAEDEGDYYCFSGYVDSDSKLY

  VFGSGTQLTVL]

  J43 MP8-2 2005 Amino Acid Sequence:

  (SEQ ID NO: 1123)

  ACRICQDHPATKWNSGGGSSGGAVGLLAPPSGRSANPRGGGSYELTQPPS

  ASVNVGETVKITCSGDQLPKYFADWFHQRSDQTILQVIYDDNKRPSGIPE

  RISGSSSGTTATLTIRDVRAEDEGDYYCFSGYVDSDSKLYVFGSGTQLTV

  L

  [Spacer (SEQ ID NO: 362)]

  [J43 MP8-2 2008 (SEQ ID NO: 1127)

  Amino Acid Sequence:

  (SEQ ID NO: 1128)

  [QGQSGQG][ACRICQDHPATKWNSGGGSSGGSISSGLLSGRSDGHGGGS

  YELTQPPSASVNVGETVKITCSGDQLPKYFADWFHQRSDQTILQVIYDDN

  KRPSGIPERISGSSSGTTATLTIRDVRAEDEGDYYCFSGYVDSDSKLYVF

  GSGTQLTVL]

  J43 MP8-2 2008 Amino Acid Sequence:

  (SEQ ID NO: 1127)

  ACRICQDHPATKWNSGGGSSGGSISSGLLSGRSDGHGGGSYELTQPPSAS

  VNVGETVKITCSGDQLPKYFADWFHQRSDQTILQVIYDDNKRPSGIPERI

  SGSSSGTTATLTIRDVRAEDEGDYYCFSGYVDSDSKLYVFGSGTQLTVL

  [Spacer (SEQ ID NO: 918)]

  [J43 MP8-2 2008 (SEQ ID NO: 1129)

  Nucleotide Sequence:

  (SEQ ID NO: 1130)

  [CAAGGCCAGTCTGGCCAAGGT][GCGTGCCGTATTTGTCAGGATCATCC

  TGCGACGAAGTGGAATTCTGGAGGTGGCTCGAGCGGCGGCTCTATCTCTT

  CCGGACTGCTGTCCGGCAGATCCGACCAGCACGGCGGAGGATCCTACGA

  GCTGACCCAGCCTCCTAGCGCCTCCGTGAATGTGGGCGAGACAGTGAAG

  ATCACCTGTAGCGGCGACCAGCTGCCCAAGTACTTCGCCGACTGGTTCC

  ACCAGCGGAGCGACCAGACAATCCTGCAAGTGATCTACGACGACAACA

  AGCGGCCCAGCGGCATCCCCGAGAGAATCAGCGGAAGCAGCAGCGGC

  ACCACCGCCACCCTGACCATTAGAGATGTGCGGGCCGAGGACGAGGG

  CGACTACTACTGCTTTAGCGGCTACGTGGACAGCGACAGCAAGCTGTAC

  GTGTTCGGCTCCGGTACCCAGCTGACAGTGCTG]

  [Spacer (SEQ ID NO: 362)]

  [J43 MP8-2 2012 (SEQ ID NO: 1131)

  Amino Acid Sequence:

  (SEQ ID NO: 1132)

  [QGQSGQG][ACRICQDHPATKWNSGGGSSGGSISSGLLSGRSANPGGG

  SYELTQPPSASVNVGETVKITCSGDQLPKYFADWFHQRSDQTILQVIYDD

  NKRPSGIPERISGSSSGTTATLTIRDVRAEDEGDYYCFSGYVDSDSKLYV

  FGSGTQLTVL]

  J43 MP8-2 2012 Amino Acid Sequence:

  (SEQ ID NO: 1131)

  ACRICQDHPATKWNSGGGSSGGSISSGLLSGRSANPGGGSYELTQPPSAS

  VNVGETVKITCSGDQLPKYFADWFHQRSDQTILQVIYDDNKRPSGIPERI

  SGSSSGTTATLTIRDVRAEDEGDYYCFSGYVDSDSKLYVFGSGTQLTVL

  [Spacer (SEQ ID NO: 918)]

  [J43 MP8-2 2012 (SEQ ID NO: 616)

  Nucleotide Sequence:

  (SEQ ID NO: 1133)

  [CAAGGCCAGTCTGGCCAAGGT][GCGTGCCGTATTTGTCAGGATCATC

  CTGCGACGAAGTGGAATTCTGGAGGTGGCTCGAGCGGCGGCTCTATC

  TCTTCCGGACTGCTGTCCGGCAGATCCGCTAATCCCGGCGGAGGA

  TCCTACGAGCTGACCCAGCCTCCTAGCGCCTCCGTGAATGTGGGCGAGA

  CAGTGAAGATCACCTGTAGCGGCGACCAGCTGCCCAAGTACTTCGCCGA

  CTGGTTCCACCAGCGGAGCGACCAGACAATCCTGCAAGTGATCTACGAC

  GACAACAAGCGGCCCAGCGGCATCCCCGAGAGAATCAGCGGAAGCAGCA

  GCGGCACCACCGCCACCCTGACCATTAGAGATGTGCGGGCCGAGGACGA

  GGGCGACTACTACTGCTTTAGCGGCTACGTGGACAGCGACAGCAAGCTG

  TACGTGTTCGGCTCCGGTACCCAGCTGACAGTGCTG]

  [Spacer (SEQ ID NO: 362)]

  [J43 MP8-2 2011 (SEQ ID NO: 1134)

  Amino Acid Sequence:

  (SEQ ID NO: 1135)

  [QGQSGQG][ACRICQDHPATKWNSGGGSSGGSISSGLLSGRSDNP

  GGGSYELTQPPSASVNVGETVKITCSGDQLPKYFADWFHQRSDQTI

  LQVIYDDNKRPSGIPERISGSSSGTTATLTIRDVRAEDEGDYYCFSGYV

  DSDSKLYVFGSGTQLTVL]

  J43 MP8-2 2011 Amino Acid Sequence:

  (SEQ ID NO: 1134)

  ACRICQDHPATKWNSGGGSSGGSISSGLLSGRSDNPGGGSYELTQPPSAS

  VNVGETVKITCSGDQLPKYFADWFHQRSDQTILQVIYDDNKRPSGIPERI

  SGSSSGTTATLTIRDVRAEDEGDYYCFSGYVDSDSKLYVFGSGTQLTVL

  [Spacer (SEQ ID NO: 918)]

  [J43 MP8-2 2011 (SEQ ID NO: 1136)

  Nucleotide Sequence:

  (SEQ ID NO: 1137)

  [CAAGGCCAGTCTGGCCAAGGT][GCGTGCCGTATTTGTCAGGATCA

  TCCTGCGACGAAGTGGAATTCTGGAGGTGGCTCGAGCGGCGGCTC

  TATCTCTTCCGGACTGCTGTCCGGCAGATCCGACAATCCCGGCGGAGGA

  TCCTACGAGCTGACCCAGCCTCCTAGCGCCTCCGTGAATGTGGGCGAGA

  CAGTGAAGATCACCTGTAGCGGCGACCAGCTGCCCAAGTACTTCGCCGA

  CTGGTTCCACCAGCGGAGCGACCAGACAATCCTGCAAGTGATCTACGAC

  GACAACAAGCGGCCCAGCGGCATCCCCGAGAGAATCAGCGGAAGCAGCA

  GCGGCACCACCGCCACCCTGACCATTAGAGATGTGCGGGCCGAGGACGA

  GGGCGACTACTACTGCTTTAGCGGCTACGTGGACAGCGACAGCAAGCTG

  TACGTGTTCGGCTCCGGTACCCAGCTGACAGTGCTG]

Example 17: Activatable Anti-Mouse PD-1 J43 Antibodies Reduce Incidence of Diabetes in NOD Mice
• In this Example, anti-PD-1 J43 activatable antibodies were analyzed for the ability to protect from anti-PD-1 induction of diabetes in NOD mice. The NOD mice, substrain NOD/ShiLtJ, were obtained from Jackson Laboratory at 8 weeks and acclimated on site for 2 weeks. At 10 weeks, mice were checked for diabetes prior to enrollment, grouped, and dosed as set forth in Table 4.

• TABLE 4
  Dosing regimen

  					Dose
  				Dose	volume
  Group	Count	Gender	Treatment	(mg/kg)	(mL/kg)	Schedule	Route

  1	7	F	mIgG2a (C1.18.4)	10	10	q7dx1	IP
  2	7	F	Anti-PD-1 J43 m2a	10	10	q7dx1	IP
  3	7	F	Anti-PD-1 J43 m2a	3	10	q7dx1	IP
  4	7	F	Anti-PD-1 J43 m2a	1	10	q7dx1	IP
  5	7	F	J43 MP7-1 2001 m2a	10	10	q7dx1	IP
  6	7	F	J43 MP7-1 2001 m2a	3	10	q7dx1	IP
  7	7	F	J43 MP8-2 2001 m2a	10	10	q7dx1	IP
  8	7	F	J43 MP8-2 2001 m2a	3	10	q7dx1	IP

• FIG. 24 which plots % non-diabetic versus number of days post dose, shows that anti-PD-1 J43 antibody induced diabetes in NOD mice with increased frequency as dosage increased. At day fourteen post dose, the percentage of non-diabetic mice for the antibody-treated groups was 14%, 43% and 71% for the 20 mg/kg, 3 mg/kg and 1 mg/kg dose groups, respectively. Activatable antibodies J43 MP7-1 2001 m2a and J43 MP8-2 2001 m2a required increased doses to induce diabetes at frequencies comparable to the parental antibody. At day fourteen post dose with J43 MP7-1 2001 m2a, 57% of the 20 mg/kg group remained non-diabetic and all of the 3 mg/kg were non-diabetic. At day fourteen post dose with J43 MP8-2 2001 m2a, 71% of the 20 mg/kg group and 86% of the 3 mg/kg group remained non-diabetic.
Example 18: Evaluation of Efficiency of Masking Moieties
• This example describes additional activatable anti-PD-1 antibodies that exhibit reduced binding to hPD-1.
• Examples of additional activatable antibodies of the disclosure comprising anti-PD1 antibody A1.5 and a variety of mask and substrate combinations were produced using techniques as described herein. The amino acid and nucleic acid sequences of these activatable anti-PD-1 antibody variable domains of the disclosure are provided below. Antibodies were produced as hIgG4 containing a single amino acid substitution, S228P (Angal, et al. 1993. Mol Immunol 30:105-8.) HC and hK LC format.
• Masking efficiencies of several of these activatable antibodies were determined as described herein. The results are shown in FIGS. 25A and 25B.
• In some embodiments, the activatable antibody also includes a spacer sequence. In some embodiments, the spacer is joined directly to the MM of the activatable antibody. In some embodiments, the spacer is joined directly to the MM of the activatable antibody in the structural arrangement from N-terminus to C-terminus of spacer-MM-CM-AB. In some embodiments, the spacer joined directly to the N-terminus of MM of the activatable antibody is selected from the group consisting of QGQSGQG (SEQ ID NO: 362), QGQSGQ (SEQ ID NO: 913), QGQSG (SEQ ID NO: 914), QGQS (SEQ ID NO: 915), QGQ (SEQ ID NO: 916), QG (SEQ ID NO: 917), and Q. In some embodiments, the spacer includes at least the amino acid sequence QGQSGQG (SEQ ID NO: 362). In some embodiments, the spacer includes at least the amino acid sequence QGQSGQ (SEQ ID NO: 913). In some embodiments, the spacer includes at least the amino acid sequence QGQSG (SEQ ID NO: 914). In some embodiments, the spacer includes at least the amino acid sequence QGQS (SEQ ID NO: 915), In some embodiments, the spacer includes at least the amino acid sequence QGQ (SEQ ID NO: 916). In some embodiments, the spacer includes at least the amino acid sequence QG (SEQ ID NO: 917). In some embodiments, the spacer includes at least the amino acid residue Q. In some embodiments, the activatable antibody does not include a spacer sequence. Additional examples of spacers include GQSGQG (SEQ ID NO: 2042), QSGQG (SEQ ID NO: 2043), SGQG (SEQ ID NO: 2044), GQG(SEQ ID NO: 2045), QG(SEQ ID NO: 2046), and G.
• While the sequences shown below include the spacer sequence of SEQ ID NO: 362, those of ordinary skill in the art appreciate that the activatable anti-PD-1 antibodies of the disclosure can include any suitable spacer sequence, such as, for example, a spacer sequence selected from the group consisting of QGQSGQG (SEQ ID NO: 362), QGQSGQ (SEQ ID NO: 913), QGQSG (SEQ ID NO: 914), QGQS (SEQ ID NO: 915), QGQ (SEQ ID NO: 916), QG (SEQ ID NO: 917), and Q. Additional examples of spacers include GQSGQG (SEQ ID NO: 2042), QSGQG (SEQ ID NO: 2043), SGQG (SEQ ID NO: 2044), GQG(SEQ ID NO: 2045), QG(SEQ ID NO: 2046), and G While the sequences shown below include the spacer sequence of SEQ ID NO: 362, those of ordinary skill in the art will also appreciate that activatable anti-PD-1 antibodies of the disclosure in some embodiments do not include a spacer sequence.

• [Spacer (SEQ ID NO: 362)]

  [PD1 1.5 PD01 2003 (SEQ ID NO: 1138)

  Amino Acid Sequence:

  (SEQ ID NO: 1139)

  [QGQSGQG][AMSGCSWSAFCPYLAGGGSSGGSISSGLLSGRSANPR

  GGGSDIQLTQSPSSLSASVGDRVTITCRASESVDAYGISFMNWFQ

  QKPGKAPKLLIYAASNQGSGVPSRFSGSGSGTDFTLTISSMQPEDFATY

  YCQQSKDVPWTFGQGTKLEIK]

  PD1 1.5 PD01 2003 Amino Acid Sequence:

  (SEQ ID NO: 1138)

  AMSGCSWSAFCPYLAGGGSSGGSISSGLLSGRSANPRGGGSDIQLTQSPS

  SLSASVGDRVTITCRASESVDAYGISFMNWFQQKPGKAPKLLIYAASNQG

  SGVPSRFSGSGSGTDFTLTISSMQPEDFATYYCQQSKDVPWTFGQGTKLE

  IK

  [Spacer (SEQ ID NO: 918)]

  [PD1 1.5 PD001 2003 (SEQ ID NO: 1141)]

  Nucleotide Sequence:

  (SEQ ID NO: 1142)

  [CAAGGCCAGTCTGGCCAAGGT][GCGATGAGTGGGTGCTCGTGGT

  CTGCTTTTTGCCCGTATTTGGCGGGAGGTGGCTCGAGCGGCGGCTC

  TATCTCTTCCGGACTGCTGTCCGGCAGATCCGCCAATCCTCGTGGCGGA

  GGATCCGATATCCAGCTGACCCAGAGCCCTAGCAGCCTGTCTGCCAGCG

  TGGGCGACAGAGTGACCATCACCTGTAGAGCCAGCGAGAGCGTGGACGC

  TTACGGCATCAGCTTCATGAACTGGTTCCAGCAGAAGCCCGGCAAGGCC

  CCCAAGCTGCTGATCTACGCCGCCAGCAATCAGGGCAGCGGCGTGCCAA

  GCAGATTTTCCGGCTCTGGCAGCGGCACCGACTTCACCCTGACCATCAG

  CAGCATGCAGCCCGAGGACTTCGCCACCTACTACTGCCAGCAGAGCAAG

  GACGTGCCCTGGACCTTTGGCCAGGGTACCAAGCTGGAAATCAAG]

  [Spacer (SEQ ID NO: 362)]

  [PD1 1.5 PD01 2012 (SEQ ID NO: 1144)

  Amino Acid Sequence:

  (SEQ ID NO: 1143)

  [QGQSGQG][AMSGCSWSAFCPYLGGGSSGGSISSGLLSGRSANPGG

  GSDIQLTQSPSSLSASVGDRVTITCRASESVDAYGISFMNWFQQK

  PGKAPKLLIYAASNQGSGVPSRFSGSGSGTDFTLTISSMQPEDFATYYC

  QQSKDVPWTFGQGTKLEIK]

  PD1 1.5 PD01 2012 Amino Acid Sequence:

  (SEQ ID NO: 1144)

  AMSGCSWSAFCPYLGGGSSGGSISSGLLSGRSANPGGGSDIQLTQSPSSL

  SASVGDRVTITCRASESVDAYGISFMNWFQQKPGKAPKLLIYAASNQGSG

  VPSRFSGSGSGTDFTLTISSMQPEDFATYYCQQSKDVPWTFGQGTKLEIK

  [Spacer (SEQ ID NO: 918)]

  [PD1 1.5 PD01 2012 (SEQ ID NO: 1145)]

  Nucleotide Sequence:

  (SEQ ID NO: 1146)

  [CAAGGCCAGTCTGGCCAAGGT][GCGATGAGTGGGTGCTCGTGGTC

  TGCTTTTTGCCCGTATTTGGCGGGAGGTGGCTCGAGCGGCGGCTC

  TATCTCTTCCGGACTGCTGTCCGGCAGATCCGCTAATCCCGGCGGAGGA

  TCCGATATCCAGCTGACCCAGAGCCCTAGCAGCCTGTCTGCCAGCGTGG

  GCGACAGAGTGACCATCACCTGTAGAGCCAGCGAGAGCGTGGACGCTTA

  CGGCATCAGCTTCATGAACTGGTTCCAGCAGAAGCCCGGCAAGGCCCCC

  AAGCTGCTGATCTACGCCGCCAGCAATCAGGGCAGCGGCGTGCCAAGCA

  GATTTTCCGGCTCTGGCAGCGGCACCGACTTCACCCTGACCATCAGCAG

  CATGCAGCCCGAGGACTTCGCCACCTACTACTGCCAGCAGAGCAAGGAC

  GTGCCCTGGACCTTTGGCCAGGGTACCAAGCTGGAAATCAAG]

  [Spacer (SEQ ID NO: 362)]

  [PD1 1.5 PD01 2011 (SEQ ID NO: 1148)

  Amino Acid Sequence:

  (SEQ ID NO: 1147)

  [QGQSGQG][AMSGCSWSAFCPYLGGGSSGGSISSGLLSGRSDNPG

  GGSDIQLTQSPSSLSASVGDRVTITCRASESVDAYGISFMNWFQQK

  PGKAPKLLIYAASNQGSGVPSRFSGSGSGTDFTLTISSMQPEDFATYYC

  QQSKDVPWTFGQGTKLEIK]

  PD1 1.5 PD01 2011 Amino Acid Sequence:

  (SEQ ID NO: 1148)

  AMSGCSWSAFCPYLGGGSSGGSISSGLLSGRSDNPGGGSDIQLTQSPSSL

  SASVGDRVTITCRASESVDAYGISFMNWFQQKPGKAPKLLIYAASNQGSG

  VPSRFSGSGSGTDFTLTISSMQPEDFATYYCQQSKDVPWTFGQGTKLEIK

  [Spacer (SEQ ID NO: 918)]

  [PD1 1.5 PD01 2011 (SEQ ID NO: 1149)]

  Nucleotide Sequence:

  (SEQ ID NO: 1150)

  [CAAGGCCAGTCTGGCCAAGGT][GCGATGAGTGGGTGCTCGTGGTCTGC

  TTTTTGCCCGTATTTGGCGGGAGGTGGCTCGAGCGGCGGCTCTATCTCTT

  CCGGACTGCTGTCCGGCAGATCCGACAATCCCGGCGGAGGATCCGATATC

  CAGCTGACCCAGAGCCCTAGCAGCCTGTCTGCCAGCGTGGGCGACAGAGT

  GACCATCACCTGTAGAGCCAGCGAGAGCGTGGACGCTTACGGCATCAGCT

  TCATGAACTGGTTCCAGCAGAAGCCCGGCAAGGCCCCCAAGCTGCTGATC

  TACGCCGCCAGCAATCAGGGCAGCGGCGTGCCAAGCAGATTTTCCGGCTC

  TGGCAGCGGCACCGACTTCACCCTGACCATCAGCAGCATGCAGCCCGAGG

  ACTTCGCCACCTACTACTGCCAGCAGAGCAAGGACGTGCCCTGGACCTTT

  GGCCAGGGTACCAAGCTGGAAATCAAG]

  [Spacer (SEQ ID NO: 362)]

  [PD1 1.5 PD34 2001 (SEQ ID NO: 1152)

  Amino Acid Sequence:

  (SEQ ID NO: 1151)

  [QGQSGQG][TSYCSIEHYPCNTHHGGGSSGGSISSGLLSGRSDNHGGGS

  DIQLTQSPSSLSASVGDRVTITCRASESVDAYGISFMNWFQQKPGKAPKL

  LIYAASNQGSGVPSRFSGSGSGTDFTLTISSMQPEDFATYYCQQSKDVPW

  TFGQGTKLEIK]

  PD1 1.5 PD34 2001 Amino Acid Sequence:

  (SEQ ID NO: 1152)

  TSYCSIEHYPCNTHHGGGSSGGSISSGLLSGRSDNHGGGSDIQLTQSPSS

  LSASVGDRVTITCRASESVDAYGISFMNWFQQKPGKAPKLLIYAASNQGS

  GVPSRFSGSGSGTDFTLTISSMQPEDFATYYCQQSKDVPWTFGQGTKLEI

  K

  [Spacer (SEQ ID NO: 1125)]

  [PD1 1.5 PD034 2001 (SEQ ID NO: 1153)]

  Nucleotide Sequence:

  (SEQ ID NO: 1154)

  [CAGGGGCAATCTGGCCAGGGG][ACGTCTTACTGCAGTATTGAGCATTA

  CCCCTGCAATACACATCATGGAGGTGGCTCGAGCGGCGGCTCTATCTCTT

  CCGGACTGCTGTCCGGCAGATCCGACAATCACGGCGGAGGATCCGATATC

  CAGCTGACCCAGAGCCCTAGCAGCCTGTCTGCCAGCGTGGGCGACAGAGT

  GACCATCACCTGTAGAGCCAGCGAGAGCGTGGACGCTTACGGCATCAGCT

  TCATGAACTGGTTCCAGCAGAAGCCCGGCAAGGCCCCCAAGCTGCTGATC

  TACGCCGCCAGCAATCAGGGCAGCGGCGTGCCAAGCAGATTTTCCGGCTC

  TGGCAGCGGCACCGACTTCACCCTGACCATCAGCAGCATGCAGCCCGAGG

  ACTTCGCCACCTACTACTGCCAGCAGAGCAAGGACGTGCCCTGGACCTTT

  GGCCAGGGTACCAAGCTGGAAATCAAG]

  [Spacer (SEQ ID NO: 362)]

  [PD1 1.5 PD34 1004/GG/0001 (SEQ ID NO: 1156)

  Amino Acid

  Sequence:

  (SEQ ID NO: 1155)

  [QGQSGQG][TSYCSIEHYPCNTHHGGGSSGGSAVGLLAPPGGLSGRSDN

  HGGGSDIQLTQSPSSLSASVGDRVTITCRASESVDAYGISFMNWFQQKPG

  KAPKLLIYAASNQGSGVPSRFSGSGSGTDFTLTISSMQPEDFATYYCQQS

  KDVPWTFGQGTKLEIK]

  PD1 1.5 PD34 1004/GG/0001 Amino Acid Sequence:

  (SEQ ID NO: 1156)

  TSYCSIEHYPCNTHHGGGSSGGSAVGLLAPPGGLSGRSDNHGGGSDIQLT

  QSPSSLSASVGDRVTITCRASESVDAYGISFMNWFQQKPGKAPKLLIYAA

  SNQGSGVPSRFSGSGSGTDFTLTISSMQPEDFATYYCQQSKDVPWTFGQG

  TKLEIK

  [Spacer (SEQ ID NO: 362)]

  [PD1 1.5 PD34 2005 (SEQ ID NO: 1160)

  Amino Acid Sequence:

  (SEQ ID NO: 1159)

  [QGQSGQG][TSYCSIEHYPCNTHHGGGSSGGSAVGLLAPPSGRSANPRG

  GGGSDIQLTQSPSSLSASVGDRVTITCRASESVDAYGISFMNWFQQKPGK

  APKLLIYAASNQGSGVPSRFSGSGSGTDFTLTISSMQPEDFATYYCQQSK

  DVPWTFGQGTKLEIK]

  PD1 1.5 PD34 2005 Amino Acid Sequence:

  (SEQ ID NO: 1160)

  TSYCSIEHYPCNTHHGGGSSGGSAVGLLAPPSGRSANPRGGGGSDIQLTQ

  SPSSLSASVGDRVTITCRASESVDAYGISFMNWFQQKPGKAPKLLIYAAS

  NQGSGVPSRFSGSGSGTDFTLTISSMQPEDFATYYCQQSKDVPWTFGQGT

  KLEIK

  [Spacer (SEQ ID NO: 362)]

  [PD1 1.5 PD34 2010 (SEQ ID NO: 1164)

  Amino Acid Sequence:

  (SEQ ID NO: 1163)

  [QGQSGQG][TSYCSIEHYPCNTHHGGGSSGGSISSGLLSGRSDYHGGGS

  DIQLTQSPSSLSASVGDRVTITCRASESVDAYGISFMNWFQQKPGKAPKL

  LIYAASNQGSGVPSRFSGSGSGTDFTLTISSMQPEDFATYYCQQSKDVPW

  TFGQGTKLEIK]

  PD1 1.5 PD34 2010 Amino Acid Sequence:

  (SEQ ID NO: 1164)

  TSYCSIEHYPCNTHHGGGSSGGSISSGLLSGRSDYHGGGSDIQLTQSPSS

  LSASVGDRVTITCRASESVDAYGISFMNWFQQKPGKAPKLLIYAASNQGS

  GVPSRFSGSGSGTDFTLTISSMQPEDFATYYCQQSKDVPWTFGQGTKLEI

  K

  [Spacer (SEQ ID NO: 362)]

  [PD1 1.5 PD34 2014 (SEQ ID NO: 1168)

  Amino Acid Sequence:

  (SEQ ID NO: 1167)

  [QGQSGQG][TSYCSIEHYPCNTHHGGGSSGGSISSGLLSGRSDNIGGGS

  DIQLTQSPSSLSASVGDRVTITCRASESVDAYGISFMNWFQQKPGKAPKL

  LIYAASNQGSGVPSRFSGSGSGTDFTLTISSMQPEDFATYYCQQSKDVPW

  TFGQGTKLEIK]

  PD1 1.5 PD34 2014 Amino Acid Sequence:

  (SEQ ID NO: 1168)

  TSYCSIEHYPCNTHHGGGSSGGSISSGLLSGRSDNIGGGSDIQLTQSPSS

  LSASVGDRVTITCRASESVDAYGISFMNWFQQKPGKAPKLLIYAASNQGS

  GVPSRFSGSGSGTDFTLTISSMQPEDFATYYCQQSKDVPWTFGQGTKLEI

  K

  [Spacer (SEQ ID NO: 362)]

  [PD1 1.5 PD34 2003 (SEQ ID NO: 1170)

  Amino Acid Sequence:

  (SEQ ID NO: 1171)

  [QGQSGQG][TSYCSIEHYPCNTHHGGGSSGGSISSGLLSGRSANPRGGG

  SDIQLTQSPSSLSASVGDRVTITCRASESVDAYGISFMNWFQQKPGKAPK

  LLIYAASNQGSGVPSRFSGSGSGTDFTLTISSMQPEDFATYYCQQSKDVP

  WTFGQGTKLEIK]

  PD1 1.5 PD34 2003 Amino Acid Sequence:

  (SEQ ID NO: 1170)

  TSYCSIEHYPCNTHHGGGSSGGSISSGLLSGRSANPRGGGSDIQLTQSPS

  SLSASVGDRVTITCRASESVDAYGISFMNWFQQKPGKAPKLLIYAASNQG

  SGVPSRFSGSGSGTDFTLTISSMQPEDFATYYCQQSKDVPWTFGQGTKLE

  IK

  [Spacer (SEQ ID NO: 1125)]

  [PD1 1.5 PD034 2003 (SEQ ID NO: 1172)]

  Nucleotide Sequence:

  (SEQ ID NO: 1173)

  [CAGGGGCAATCTGGCCAGGGG][ACGTCTTACTGCAGTATTGAGCATTA

  CCCCTGCAATACACATCATGGAGGTGGCTCGAGCGGCGGCTCTATCTCTT

  CCGGACTGCTGTCCGGCAGATCCGCCAATCCTCGTGGCGGAGGATCCGAT

  ATCCAGCTGACCCAGAGCCCTAGCAGCCTGTCTGCCAGCGTGGGCGACAG

  AGTGACCATCACCTGTAGAGCCAGCGAGAGCGTGGACGCTTACGGCATCA

  GCTTCATGAACTGGTTCCAGCAGAAGCCCGGCAAGGCCCCCAAGCTGCTG

  ATCTACGCCGCCAGCAATCAGGGCAGCGGCGTGCCAAGCAGATTTTCCGG

  CTCTGGCAGCGGCACCGACTTCACCCTGACCATCAGCAGCATGCAGCCCG

  AGGACTTCGCCACCTACTACTGCCAGCAGAGCAAGGACGTGCCCTGGACC

  TTTGGCCAGGGTACCAAGCTGGAAATCAAG]

  [Spacer (SEQ ID NO: 362)]

  [PD1 1.5 PD34 2006 (SEQ ID NO: 1174)

  Amino Acid Sequence:

  (SEQ ID NO: 1175)

  [QGQSGQG][TSYCSIEHYPCNTHHGGGSSGGSISSGLLSGRSDDHGGGS

  DIQLTQSPSSLSASVGDRVTITCRASESVDAYGISFMNWFQQKPGKAPKL

  LIYAASNQGSGVPSRFSGSGSGTDFTLTISSMQPEDFATYYCQQSKDVPW

  TFGQGTKLEIK]

  PD1 1.5 PD34 2006 Amino Acid Sequence:

  (SEQ ID NO: 1174)

  TSYCSIEHYPCNTHHGGGSSGGSISSGLLSGRSDDHGGGSDIQLTQSPSS

  LSASVGDRVTITCRASESVDAYGISFMNWFQQKPGKAPKLLIYAASNQGS

  GVPSRFSGSGSGTDFTLTISSMQPEDFATYYCQQSKDVPWTFGQGTKLEI

  K

  [Spacer (SEQ ID NO: 1125)]

  [PD1 1.5 PD034 2006 (SEQ ID NO: 1176)]

  Nucleotide Sequence:

  (SEQ ID NO: 1177)

  [CAGGGGCAATCTGGCCAGGGG][ACGTCTTACTGCAGTATTGAGCATTA

  CCCCTGCAATACACATCATGGAGGTGGCTCGAGCGGCGGCTCTATCTCTT

  CCGGACTGCTGTCCGGCAGATCCGACGATCACGGCGGAGGATCCGATATC

  CAGCTGACCCAGAGCCCTAGCAGCCTGTCTGCCAGCGTGGGCGACAGAGT

  GACCATCACCTGTAGAGCCAGCGAGAGCGTGGACGCTTACGGCATCAGCT

  TCATGAACTGGTTCCAGCAGAAGCCCGGCAAGGCCCCCAAGCTGCTGATC

  TACGCCGCCAGCAATCAGGGCAGCGGCGTGCCAAGCAGATTTTCCGGCTC

  TGGCAGCGGCACCGACTTCACCCTGACCATCAGCAGCATGCAGCCCGAGG

  ACTTCGCCACCTACTACTGCCAGCAGAGCAAGGACGTGCCCTGGACCTTT

  GGCCAGGGTACCAAGCTGGAAATCAAG]

  [Spacer (SEQ ID NO: 362)]

  [PD1 1.5 PD34 2007 (SEQ ID NO: 1178)

  Amino Acid Sequence:

  (SEQ ID NO: 1179)

  [QGQSGQG][TSYCSIEHYPCNTHHGGGSSGGSISSGLLSGRSDIHGGGS

  DIQLTQSPSSLSASVGDRVTITCRASESVDAYGISFMNWFQQKPGKAPKL

  LIYAASNQGSGVPSRFSGSGSGTDFTLTISSMQPEDFATYYCQQSKDVPW

  TFGQGTKLEIK]

  PD1 1.5 PD34 2007 Amino Acid Sequence:

  (SEQ ID NO: 1178)

  TSYCSIEHYPCNTHHGGGSSGGSISSGLLSGRSDIHGGGSDIQLTQSPSS

  LSASVGDRVTITCRASESVDAYGISFMNWFQQKPGKAPKLLIYAASNQGS

  GVPSRFSGSGSGTDFTLTISSMQPEDFATYYCQQSKDVPWTFGQGTKLEI

  K

  [Spacer (SEQ ID NO: 1125)]

  [PD1 1.5 PD034 2007 (SEQ ID NO: 1180)]

  Nucleotide Sequence:

  (SEQ ID NO: 1181)

  [CAGGGGCAATCTGGCCAGGGG][ACGTCTTACTGCAGTATTGAGCATTA

  CCCCTGCAATACACATCATGGAGGTGGCTCGAGCGGCGGCTCTATCTCTT

  CCGGACTGCTGTCCGGCAGATCCGACATTCACGGCGGAGGATCCGATATC

  CAGCTGACCCAGAGCCCTAGCAGCCTGTCTGCCAGCGTGGGCGACAGAGT

  GACCATCACCTGTAGAGCCAGCGAGAGCGTGGACGCTTACGGCATCAGCT

  TCATGAACTGGTTCCAGCAGAAGCCCGGCAAGGCCCCCAAGCTGCTGATC

  TACGCCGCCAGCAATCAGGGCAGCGGCGTGCCAAGCAGATTTTCCGGCTC

  TGGCAGCGGCACCGACTTCACCCTGACCATCAGCAGCATGCAGCCCGAGG

  ACTTCGCCACCTACTACTGCCAGCAGAGCAAGGACGTGCCCTGGACCTTT

  GGCCAGGGTACCAAGCTGGAAATCAAG]

  [Spacer (SEQ ID NO: 362)]

  [PD1 1.5 PD34 2009 (SEQ ID NO: 1182)

  Amino Acid Sequence:

  (SEQ ID NO: 1183)

  [QGQSGQG][TSYCSIEHYPCNTHHGGGSSGGSISSGLLSGRSDTHGGGS

  DIQLTQSPSSLSASVGDRVTITCRASESVDAYGISFMNWFQQKPGKAPKL

  LIYAASNQGSGVPSRFSGSGSGTDFTLTISSMQPEDFATYYCQQSKDVPW

  TFGQGTKLEIK]

  [PD1 1.5 PD34 2009 Amino Acid Sequence:

  (SEQ ID NO: 1182)

  TSYCSIEHYPCNTHHGGGSSGGSISSGLLSGRSDTHGGGSDIQLTQSPSS

  LSASVGDRVTITCRASESVDAYGISFMNWFQQKPGKAPKLLIYAASNQGS

  GVPSRFSGSGSGTDFTLTISSMQPEDFATYYCQQSKDVPWTFGQGTKLEI

  K

  [Spacer (SEQ ID NO: 1125)]

  [PD1 1.5 PD034 2009 (SEQ ID NO: 1184)]

  Nucleotide Sequence:

  (SEQ ID NO: 1185)

  [CAGGGGCAATCTGGCCAGGGG][ACGTCTTACTGCAGTATTGAGCATTA

  CCCCTGCAATACACATCATGGAGGTGGCTCGAGCGGCGGCTCTATCTCTT

  CCGGACTGCTGTCCGGCAGATCCGACACTCACGGCGGAGGATCCGATATC

  CAGCTGACCCAGAGCCCTAGCAGCCTGTCTGCCAGCGTGGGCGACAGAGT

  GACCATCACCTGTAGAGCCAGCGAGAGCGTGGACGCTTACGGCATCAGCT

  TCATGAACTGGTTCCAGCAGAAGCCCGGCAAGGCCCCCAAGCTGCTGATC

  TACGCCGCCAGCAATCAGGGCAGCGGCGTGCCAAGCAGATTTTCCGGCTC

  TGGCAGCGGCACCGACTTCACCCTGACCATCAGCAGCATGCAGCCCGAGG

  ACTTCGCCACCTACTACTGCCAGCAGAGCAAGGACGTGCCCTGGACCTTT

  GGCCAGGGTACCAAGCTGGAAATCAAG]

  [Spacer (SEQ ID NO: 362)]

  [PD1 1.5 PD34 2008 (SEQ ID NO: 1186)

  Amino Acid Sequence:

  (SEQ ID NO: 1187)

  [QGQSGQG][TSYCSIEHYPCNTHHGGGSSGGSISSGLLSGRSDQHGGGS

  DIQLTQSPSSLSASVGDRVTITCRASESVDAYGISFMNWFQQKPGKAPKL

  LIYAASNQGSGVPSRFSGSGSGTDFTLTISSMQPEDFATYYCQQSKDVPW

  TFGQGTKLEIK]

  PD1 1.5 PD34 2008 Amino Acid Sequence:

  (SEQ ID NO: 1186)

  TSYCSIEHYPCNTHHGGGSSGGSISSGLLSGRSDQHGGGSDIQLTQSPSS

  LSASVGDRVTITCRASESVDAYGISFMNWFQQKPGKAPKLLIYAASNQGS

  GVPSRFSGSGSGTDFTLTISSMQPEDFATYYCQQSKDVPWTFGQGTKLEI

  K

  [Spacer (SEQ ID NO: 1125)]

  [PD1 1.5 PD034 2008 (SEQ ID NO: 1188)]

  Nucleotide Sequence:

  (SEQ ID NO: 1189)

  [CAGGGGCAATCTGGCCAGGGG][ACGTCTTACTGCAGTATTGAGCATTA

  CCCCTGCAATACACATCATGGAGGTGGCTCGAGCGGCGGCTCTATCTCTT

  CCGGACTGCTGTCCGGCAGATCCGACCAGCACGGCGGAGGATCCGATATC

  CAGCTGACCCAGAGCCCTAGCAGCCTGTCTGCCAGCGTGGGCGACAGAGT

  GACCATCACCTGTAGAGCCAGCGAGAGCGTGGACGCTTACGGCATCAGCT

  TCATGAACTGGTTCCAGCAGAAGCCCGGCAAGGCCCCCAAGCTGCTGATC

  TACGCCGCCAGCAATCAGGGCAGCGGCGTGCCAAGCAGATTTTCCGGCTC

  TGGCAGCGGCACCGACTTCACCCTGACCATCAGCAGCATGCAGCCCGAGG

  ACTTCGCCACCTACTACTGCCAGCAGAGCAAGGACGTGCCCTGGACCTTT

  GGCCAGGGTACCAAGCTGGAAATCAAG]

  [Spacer (SEQ ID NO: 362)]

  [PD1 1.5 PD34 2012 (SEQ ID NO: 1190)

  Amino Acid Sequence:

  (SEQ ID NO: 1191)

  [QGQSGQG][TSYCSIEHYPCNTHHGGGSSGGSISSGLLSGRSANPGGGS

  DIQLTQSPSSLSASVGDRVTITCRASESVDAYGISFMNWFQQKPGKAPKL

  LIYAASNQGSGVPSRFSGSGSGTDFTLTISSMQPEDFATYYCQQSKDVPW

  TFGQGTKLEIK]

  PD1 1.5 PD34 2012 Amino Acid Sequence:

  (SEQ ID NO: 1190)

  TSYCSIEHYPCNTHHGGGSSGGSISSGLLSGRSANPGGGSDIQLTQSPSS

  LSASVGDRVTITCRASESVDAYGISFMNWFQQKPGKAPKLLIYAASNQGS

  GVPSRFSGSGSGTDFTLTISSMQPEDFATYYCQQSKDVPWTFGQGTKLEI

  K

  [Spacer (SEQ ID NO: 1125)]

  [PD1 1.5 PD034 2012 (SEQ ID NO: 1192)]

  Nucleotide Sequence:

  (SEQ ID NO: 1193)

  [CAGGGGCAATCTGGCCAGGGG][ACGTCTTACTGCAGTATTGAGCAT

  TACCCCTGCAATACACATCATGGAGGTGGCTCGAGCGGCGGCTCTATCT

  CTTCCGGACTGCTGTCCGGCAGATCCGCTAATCCCGGCGGAGGATCCG

  ATATCCAGCTGACCCAGAGCCCTAGCAGCCTGTCTGCCAGCGTGGGCGA

  CAGAGTGACCATCACCTGTAGAGCCAGCGAGAGCGTGGACGCTTACGGCA

  TCAGCTTCATGAACTGGTTCCAGCAGAAGCCCGGCAAGGCCCCCAAGCTG

  CTGATCTACGCCGCCAGCAATCAGGGCAGCGGCGTGCCAAGCAGATTTTC

  CGGCTCTGGCAGCGGCACCGACTTCACCCTGACCATCAGCAGCATGCAGC

  CCGAGGACTTCGCCACCTACTACTGCCAGCAGAGCAAGGACGTGCCCTGG

  ACCTTTGGCCAGGGTACCAAGCTGGAAATCAAG]

  [Spacer (SEQ ID NO: 362)]

  [PD1 1.5 PD34 2013 (SEQ ID NO: 1194)

  Amino Acid Sequence:

  (SEQ ID NO: 1195)

  [QGQSGQG][TSYCSIEHYPCNTHHGGGSSGGSISSGLLSGRSANIG

  GGSDIQLTQSPSSLSASVGDRVTITCRASESVDAYGISFMNWFQQKPGK

  APKLLIYAASNQGSGVPSRFSGSGSGTDFTLTISSMQPEDFATYYCQQS

  KDVPWTFGQGTKLEIK]

  PD1 1.5 PD34 2013 Amino Acid Sequence:

  (SEQ ID NO: 1194)

  TSYCSIEHYPCNTHHGGGSSGGSISSGLLSGRSANIGGGSDIQLTQSPSS

  LSASVGDRVTITCRASESVDAYGISFMNWFQQKPGKAPKLLIYAASNQGS

  GVPSRFSGSGSGTDFTLTISSMQPEDFATYYCQQSKDVPWTFGQGTKLEI

  K

  [Spacer (SEQ ID NO: 1125)]

  [PD1 1.5 PD034 2013 (SEQ ID NO: 1196)]

  Nucleotide Sequence:

  (SEQ ID NO: 1197)

  [CAGGGGCAATCTGGCCAGGGG][ACGTCTTACTGCAGTATTGAGCA

  TTACCCCTGCAATACACATCATGGAGGTGGCTCGAGCGGCGGCTCTATC

  TCTTCCGGACTGCTGTCCGGCAGATCCGCTAATATTGGCGGAGGATCCG

  ATATCCAGCTGACCCAGAGCCCTAGCAGCCTGTCTGCCAGCGTGGGCGA

  CAGAGTGACCATCACCTGTAGAGCCAGCGAGAGCGTGGACGCTTACGGCA

  TCAGCTTCATGAACTGGTTCCAGCAGAAGCCCGGCAAGGCCCCCAAGCTG

  CTGATCTACGCCGCCAGCAATCAGGGCAGCGGCGTGCCAAGCAGATTTTC

  CGGCTCTGGCAGCGGCACCGACTTCACCCTGACCATCAGCAGCATGCAGC

  CCGAGGACTTCGCCACCTACTACTGCCAGCAGAGCAAGGACGTGCCCTGG

  ACCTTTGGCCAGGGTACCAAGCTGGAAATCAAG]

  [Spacer (SEQ ID NO: 362)]

  [PD1 1.5 PD34 2011 (SEQ ID NO: 1198)

  Amino Acid Sequence:

  (SEQ ID NO: 1199)

  [QGQSGQG][TSYCSIEHYPCNTHHGGGSSGGSISSGLLSGRSDNPG

  GGSDIQLTQSPSSLSASVGDRVTITCRASESVDAYGISFMNWFQQKPGK

  APKLLIYAASNQGSGVPSRFSGSGSGTDFTLTISSMQPEDFATYYCQQS

  KDVPWTFGQGTKLEIK]

  PD1 1.5 PD34 2011 Amino Acid Sequence:

  (SEQ ID NO: 1198)

  TSYCSIEHYPCNTHHGGGSSGGSISSGLLSGRSDNPGGGSDIQLTQSPSS

  LSASVGDRVTITCRASESVDAYGISFMNWFQQKPGKAPKLLIYAASNQGS

  GVPSRFSGSGSGTDFTLTISSMQPEDFATYYCQQSKDVPWTFGQGTKLEI

  K

  [Spacer (SEQ ID NO: 1125)]

  [PD1 1.5 PD034 2011 (SEQ ID NO: 1200)]

  Nucleotide Sequence:

  (SEQ ID NO: 1201)

  [CAGGGGCAATCTGGCCAGGGG][ACGTCTTACTGCAGTATTGAGCAT

  TACCCCTGCAATACACATCATGGAGGTGGCTCGAGCGGCGGCTCTATCT

  CTTCCGGACTGCTGTCCGGCAGATCCGACAATCCCGGCGGAGGATCCGA

  TATCCAGCTGACCCAGAGCCCTAGCAGCCTGTCTGCCAGCGTGGGCGAC

  AGAGTGACCATCACCTGTAGAGCCAGCGAGAGCGTGGACGCTTACGGCA

  TCAGCTTCATGAACTGGTTCCAGCAGAAGCCCGGCAAGGCCCCCAAGCTG

  CTGATCTACGCCGCCAGCAATCAGGGCAGCGGCGTGCCAAGCAGATTTTC

  CGGCTCTGGCAGCGGCACCGACTTCACCCTGACCATCAGCAGCATGCAGC

  CCGAGGACTTCGCCACCTACTACTGCCAGCAGAGCAAGGACGTGCCCTGG

  ACCTTTGGCCAGGGTACCAAGCTGGAAATCAAG]

  [Spacer (SEQ ID NO: 362)]

  [PD1 1.5 PD006 2003 (SEQ ID NO: 1202)

  Amino Acid Sequence:

  (SEQ ID NO: 1203)

  [QGQSGQG][APRCYMFASYCKSQYGGGSSGGSISSGLLSGRSANPRG

  GGSDIQLTQSPSSLSASVGDRVTITCRASESVDAYGISFMNWFQQKPGK

  APKLLIYAASNQGSGVPSRFSGSGSGTDFTLTISSMQPEDFATYYCQQS

  KDVPWTFGQGTKLEIK]

  PD1 1.5 PD006 2003 Amino Acid Sequence:

  (SEQ ID NO: 1202)

  APRCYMFASYCKSQYGGGSSGGSISSGLLSGRSANPRGGGSDIQLTQSPS

  SLSASVGDRVTITCRASESVDAYGISFMNWFQQKPGKAPKLLIYAASNQG

  SGVPSRFSGSGSGTDFTLTISSMQPEDFATYYCQQSKDVPWTFGQGTKLE

  IK

  [Spacer (SEQ ID NO: 918)]

  [PD1 1.5 PD006 2003 (SEQ ID NO: 1204)]

  Nucleotide Sequence:

  (SEQ ID NO: 1205)

  [CAAGGCCAGTCTGGCCAAGGT][GCGCCTAGGTGCTATATGTTTGCG

  TCGTATTGCAAGAGTCAGTATGGAGGTGGCTCGAGCGGCGGCTCTATCT

  CTTCCGGACTGCTGTCCGGCAGATCCGCCAATCCTCGTGGCGGAGGATC

  CGATATCCAGCTGACCCAGAGCCCTAGCAGCCTGTCTGCCAGCGTGGGC

  GACAGAGTGACCATCACCTGTAGAGCCAGCGAGAGCGTGGACGCTTACG

  GCATCAGCTTCATGAACTGGTTCCAGCAGAAGCCCGGCAAGGCCCCCAAG

  CTGCTGATCTACGCCGCCAGCAATCAGGGCAGCGGCGTGCCAAGCAGATT

  TTCCGGCTCTGGCAGCGGCACCGACTTCACCCTGACCATCAGCAGCATGC

  AGCCCGAGGACTTCGCCACCTACTACTGCCAGCAGAGCAAGGACGTGCCC

  TGGACCTTTGGCCAGGGTACCAAGCTGGAAATCAAG]

Example 19: Activatable Anti-PD1 Nivolumab Masking Moieties
• This example describes identification of masking moieties (MM) that reduce binding of anti-PD1 Nivolumab antibody to its target.
• Anti-PD1 Nivolumab (NV1) (see, e.g., U.S. Pat. No. 8,008,449) was used to screen libraries using a method similar to that described in PCT International Publication Number WO 2010/081173, published 15 Jul. 2010. The screening consisted of one round of MACS and four rounds of FACS sorting. For the initial MACS, approximately 6×10¹¹ cells were incubated with NV1 antibody at a concentration of 100 nM, and approximately 3×10⁷ binders were collected using Protein-A Dynabeads (Life Technologies, Carlsbad, Calif.). FACS rounds were conducted labeling cells with DyLight 650 (Thermo-Fisher) labeled NV1 antibody and collecting cells with strongest fluorescence as follows: 20 nM NV1-650 collecting brightest 13% for FACS round 1 (F1), 2 nM NV1-650 collecting brightest 2% for FACS round 2 (F2-1), 1 nM NV1-650 collecting brightest 1% for FACS round 3 (F3-1b) and 1 nM NV1-650 collecting two populations, the brightest 88% and the brightest 1% for FACS round 4 (F4-1b.1 and F4-1b.2). Individual peptide clones from F4-1b.1 and F4-1b.2 were identified by sequence analysis (Table 19), and selected peptide clones NV01-NV12 were subsequently verified for their ability to bind NV1 (masking moiety NV001 is also referred to herein as NV01 and/or NV-01; masking moiety NV002 is also referred to herein as NV02 and/or NV-02, and so on).

• TABLE 19
  	Mask	Amino Acid Sequence	SEQ ID NO:
  	NV01	RYCHAANPDRFCGIY	1206
  	NV02	PRVCSTDGGDYCLLP	1207
  	NV03	PRPQCHHRHNCPDHP	1208
  	NV04	KCSRPAHQNPDRCSR	1209
  	NV05	ASYRCPDYKCSHTKH	1210
  	NV06	LPRCPDHPIKCIETK	1211
  	NV07	YTFGCPDRYCDRAAT	1212
  	NV08	RGCPDFNPPSHCYTA	1213
  	NV09	RDYCGPQSPDYCHEI	1214
  	NV10	PNKPCPDLQCYVTNY	1215
  	NV11	PRVACGEPDLCYSNT	1216
  	NV12	RGCKKHTISTLTCPD	1217
  	NV13	PAYRCPDRPPCKNQM	1218
  	NV14	NARCYPYFGDNCHMN	1220
  	NV15	PTLRCPDRWCYDSPR	1221
  	NV16	PSNLCPDKWCQTWRS	1222
  	NV17	TPRYCAASYCPAHGY	1223
  	NV18	RPGCGAVSPRCPDAP	1224
  	NV19	VLRCHKQNPDNCNNH	1225
  	NV20	GVKSCREPDFCSRGS	1226
  	NV21	RNNLCPDYSCNNHNS	1227
  	NV22	RAACHRLNPDACTNG	1228
  	NV23	VCQSDRIPDYVTCTD	1229
  	NV24	RNCRIASINPDYCNI	1230
  	NV25	KEWRCPDYKCKPSYH	1231
  	NV26	NLRICHKSLCPDYIK	1232
  	NV27	NTHKCSNTNICPSFN	1233
  	NV28	STRYCQASQCQMSPY	1234
  	NV29	THRFCTASLCNKNTS	1235
  	NV30	YTLCNTRSPDWCPNK	1236
  	NV31	IRCTTGQSPDYCPQS	1237
  	NV32	RCNQPDKNDQMLCNI	1238
  	NV33	GTCRTDHQSPDYCYY	1239
  	NV34	RGCFRSGDSLGMCPD	1240
  	NV35	SGCFDSNEHRHCSRI	1241
  	NV36	NRCMKLWYNPDCVAR	1242
  	NV37	PLCARPHYWSPCDQS	1243
  	NV38	DSKCHPNSPDYCFNS	1244
  	NV39	NGSCRPLGGDFCGNR	1245
  	NV40	KTRCIEMSGDYCAKS	1246
  	NV41	IRPCMYNWGDLCNQF	1247
  	NV42	VKTCMENNPDYCYNN	1248
  	NV43	LRMCFEASGDYCDQQ	1249
  	NV44	IRKCQLDGPDQCMLT	1250
  	NV45	KWKCHKNNPNYCNNR	1251
  	NV46	RTMCLDTNPDYCQSH	1252
  	NV47	LAACHSMDSHRCPDY	1253
  	NV48	RSPCIHNATMCPDYT	1254
  	NV49	MPRCPDWPPRCSMVI	1255
  	NV50	VRQLCRLPDYCPSGK	1256
  	NV51	PRPPCAQSLNCPDRA	1257
  	NV52	SFGRCTLVRTCPDFM	1258
  	NV53	RDKPCPDFSCATIHY	1259
  	NV54	ATKPCPDRWCTMSTL	1260
  	NV55	SSNRCPDLRCTHHNM	1261
  	NV56	RGSMCPDLHCSLSHI	1262
  	NV57	NYQRCPDRTCMHNII	1263
  	NV58	QKRPCPDRKCHAHYN	1264
  	NV59	QNHRCPDRWCNKTTN	1265
  	NV60	RLNLCPDKHCHMTNL	1266
  	NV61	PQDRCPDKRCTNPGN	1267
  	NV62	SRWRCPDYKCEHGKY	1268
  	NV63	YENQCPDLYCNRYSM	1269
  	NV64	TARSCPVFNCPDNNS	1270
  	NV65	MDQRCPDAWCTSKPK	1271
  	NV66	GDLRCPDRLCPRHSL	1272
  	NV67	IQYLCPDYHCKASNN	1273
  	NV68	QHHRCPDRYCNSNNN	1274
  	NV69	TVALCPDYSCYHINN	1275
  	NV70	SPWRCPDRYCLSNHD	1276
  	NV71	SSKRCPDRFCNKTHA	1277
  	NV72	HTDRCPDYKCSQNHF	1278
  	NV73	SRSNCTPQRCNSDYH	1279
  	NV74	FAARCPDKYCAIHTN	1280
  	NV75	GSARCPDLVCQQTKQ	1281
  	NV76	RNLMCPDKFCNKNTK	1282
  	NV77	NIRLCPDKVCTPTWV	1283
  	NV78	MTDLCPDAHCAKTHM	1284
  	NV79	PYSRLCAYPCPDFVG	1285
  	NV80	LCGCARSPDYCKCRG	1286
  	NV81	WGRCERVPDCCCPRG	1287
  	NV82	TRNTCHTRICYGMAC	1288
  	NV83	CVCTSCSSYWTLCPD	1289
  	NV84	LCCSRGSNCPDRCTW	1290
  	NV85	CCPLCQANMCPDNQS	1291
  	NV86	ECKLCCPDLYCGGTM	1292
  	NV87	CSNPMCAYCCPDLIL	1293
  	NV88	CPRCNTYSKHDCYHQ	1294
  	NV89	FCCASKMPAPSNCHT	1295

Example 20: Activatable Anti-PD1 Nivolumab Antibodies
• This example describes examples of activatable anti-PD1 Nivolumab antibodies of the disclosure.
• Activatable anti-PD1 NV1 antibodies comprising an anti-PD1 NV1 masking moiety, a cleavable moiety, and an anti-PD1 NV1 antibody of the disclosure were produced according to methods similar to those described in PCT Publication Nos. WO 2009/025846 and WO 2010/081173. One embodiment of the disclosure is an anti-PD-1 activatable antibody comprising a heavy chain comprising amino acid sequence SEQ ID NO: 1346. One embodiment of the disclosure is an anti-PD-1 activatable antibody comprising a light chain comprising amino acid sequence SEQ ID NO: 626. One embodiment of the disclosure is an anti-PD-1 activatable antibody comprising a heavy chain comprising amino acid sequence SEQ ID NO: 1346 and a light chain comprising amino acid sequence SEQ ID NO: 626. One embodiment of the disclosure is an anti-PD-1 activatable antibody comprising the CDRs of an anti-PD-1 activatable antibody comprising a heavy chain comprising amino acid sequence SEQ ID NO: 1346 and a light chain comprising amino acid sequence SEQ ID NO: 626.
• The amino acid and nucleic acid sequences of several activatable anti-PD1 antibody variable domains of the disclosure are provided below. Antibodies were produced as hIgG4 containing a single amino acid substitution, S228P (Angal, et al. 1993. Mol Immunol 30:105-8.) HC and hK LC format.

• NV1 Light Chain Sequence:

  (SEQ ID NO: 626)

  EIVLTQSPATLSLSPGERATLSCRASQSVSSYLAWYQQKPGQAPRLLIY

  DASNRATGIPARFSGSGSGTDFTLTISSLEPEDFAVYYCQQSSNWPRTF

  GQGTKVEIK

  [Spacer (SEQ ID NO: 362)]

  [NV1 NV01 2001 (SEQ ID NO: 1296) Amino Acid Sequence:

  (SEQ ID NO: 1297)

  [QGQSGQG][RYCHAANPDRFCGIYGGGSSGGSISSGLLSGRSDNHGG

  SEIVLTQSPATLSLSPGERATLSCRASQSVSSYLAWYQQKPGQAPRLLI

  YDASNRATGIPARFSGSGSGTDFTLTISSLEPEDFAVYYCQQSSNWPRT

  FGQGTKVEIK]

  NV1 NV01 2001 Amino Acid Sequence:

  (SEQ ID NO: 1296)

  RYCHAANPDRFCGIYGGGSSGGSISSGLLSGRSDNHGGSEIVLTQSPATL

  SLSPGERATLSCRASQSVSSYLAWYQQKPGQAPRLLIYDASNRATGIPAR

  FSGSGSGTDFTLTISSLEPEDFAVYYCQQSSNWPRTFGQGTKVEIK

  [Spacer (SEQ ID NO: 918)]

  [NV1 NV01 2001 (SEQ ID NO: 1298)]

  Nucleotide Sequence:

  (SEQ ID NO: 1299)

  [CAAGGCCAGTCTGGCCAAGGT][CGGTATTGCCATGCTGCGAATCCT

  GATCGGTTTTGCGGTATTTATGGAGGTGGCTCGAGCGGCGGCTCTATCT

  CTTCCGGACTGCTGTCCGGCAGATCCGACAATCACGGCGGATCCGAGAT

  CGTGCTGACACAGAGCCCTGCCACCCTGTCTCTGAGCCCTGGCGAAAGA

  GCCACCCTGAGCTGTAGAGCCAGCCAGAGCGTGTCCAGCTACCTGGCCT

  GGTATCAGCAGAAGCCCGGCCAGGCTCCCCGGCTGCTGATCTACGATGCC

  AGCAATAGAGCCACCGGCATCCCCGCCAGATTTTCCGGCTCTGGCAGCGG

  CACCGACTTCACCCTGACCATCAGCTCCCTGGAACCCGAGGACTTCGCCG

  TGTACTACTGCCAGCAGAGCAGCAACTGGCCCCGGACATTTGGCCAGGGC

  ACCAAGGTGGAAATCAAG]

  [Spacer (SEQ ID NO: 362)]

  [NV1 NV02 2001 (SEQ ID NO: 1300) Amino Acid Sequence:

  (SEQ ID NO: 1301)

  [QGQSGQG][PRVCSTDGGDYCLLPGGGSSGGSISSGLLSGRSD

  NHGGSEIVLTQSPATLSLSPGERATLSCRASQSVSSYLAWYQQKPGQAPR

  LLIYDASNRATGIPARFSGSGSGTDFTLTISSLEPEDFAVYYCQQSSNWP

  RTFGQGTKVEIK]

  NV1 NV02 2001 Amino Acid Sequence:

  (SEQ ID NO: 1300)

  PRVCSTDGGDYCLLPGGGSSGGSISSGLLSGRSDNHGGSEIVLTQSPATL

  SLSPGERATLSCRASQSVSSYLAWYQQKPGQAPRLLIYDASNRATGIPAR

  FSGSGSGTDFTLTISSLEPEDFAVYYCQQSSNWPRTFGQGTKVEIK

  [Spacer (SEQ ID NO: 918)]

  [NV1 NV02 2001 (SEQ ID NO: 1302)]

  Nucleotide Sequence:

  (SEQ ID NO: 1303)

  [CAAGGCCAGTCTGGCCAAGGT][CCTAGGGTTTGCTCTACTGA

  TGGTGGTGATTATTGCTTGCTTCCTGGAGGTGGCTCGAGCGGCGGCTCTA

  TCTCTTCCGGACTGCTGTCCGGCAGATCCGACAATCACGGCGGATCCGAG

  ATCGTGCTGACACAGAGCCCTGCCACCCTGTCTCTGAGCCCTGGCGAAAG

  AGCCACCCTGAGCTGTAGAGCCAGCCAGAGCGTGTCCAGCTACCTGGCCT

  GGTATCAGCAGAAGCCCGGCCAGGCTCCCCGGCTGCTGATCTACGATGCC

  AGCAATAGAGCCACCGGCATCCCCGCCAGATTTTCCGGCTCTGGCAGCGG

  CACCGACTTCACCCTGACCATCAGCTCCCTGGAACCCGAGGACTTCGCCG

  TGTACTACTGCCAGCAGAGCAGCAACTGGCCCCGGACATTTGGCCAGGGC

  ACCAAGGTGGAAATCAAG]

  [Spacer (SEQ ID NO: 362)]

  [NV1 NV03 2001 (SEQ ID NO: 1304) Amino Acid Sequence:

  (SEQ ID NO: 1305)

  [QGQSGQG][PRPQCHHRHNCPDHPGGGSSGGSISSGLLSGRSD

  NHGGSEIVLTQSPATLSLSPGERATLSCRASQSVSSYLAWYQQKPGQAPR

  LLIYDASNRATGIPARFSGSGSGTDFTLTISSLEPEDFAVYYCQQSSNWP

  RTFGQGTKVEIK]

  (SEQ ID NO: 1304)

  PRPQCHHRHNCPDHPGGGSSGGSISSGLLSGRSDNHGGSEIVLTQSPATL

  SLSPGERATLSCRASQSVSSYLAWYQQKPGQAPRLLIYDASNRATGIPAR

  FSGSGSGTDFTLTISSLEPEDFAVYYCQQSSNWPRTFGQGTKVEIK

  [Spacer (SEQ ID NO: 918)]

  [NV1 NV03 2001 (SEQ ID NO: 1306)]

  Nucleotide Sequence:

  (SEQ ID NO: 1307)

  [CAAGGCCAGTCTGGCCAAGGT][CCTCGTCCGCAGTGCCATCA

  TCGGCATAATTGTCCTGATCATCCTGGAGGTGGCTCGAGCGGCGGCTCTA

  TCTCTTCCGGACTGCTGTCCGGCAGATCCGACAATCACGGCGGATCCGAG

  ATCGTGCTGACACAGAGCCCTGCCACCCTGTCTCTGAGCCCTGGCGAAAG

  AGCCACCCTGAGCTGTAGAGCCAGCCAGAGCGTGTCCAGCTACCTGGCCT

  GGTATCAGCAGAAGCCCGGCCAGGCTCCCCGGCTGCTGATCTACGATGCC

  AGCAATAGAGCCACCGGCATCCCCGCCAGATTTTCCGGCTCTGGCAGCGG

  CACCGACTTCACCCTGACCATCAGCTCCCTGGAACCCGAGGACTTCGCCG

  TGTACTACTGCCAGCAGAGCAGCAACTGGCCCCGGACATTTGGCCAGGGC

  ACCAAGGTGGAAATCAAG]

  [Spacer (SEQ ID NO: 362)]

  [NV1 NV04 2001 (SEQ ID NO: 1308) Amino Acid Sequence:

  (SEQ ID NO: 1309)

  [QGQSGQG][KCSRPAHQNPDRCSRGGGSSGGSISSGLLSGRSD

  NHGGSEIVLTQSPATLSLSPGERATLSCRASQSVSSYLAWYQQKPGQAPR

  LLIYDASNRATGIPARFSGSGSGTDFTLTISSLEPEDFAVYYCQQSSNWP

  RTFGQGTKVEIK]

  NV1 NV04 2001 Amino Acid Sequence:

  (SEQ ID NO: 1308)

  KCSRPAHQNPDRCSRGGGSSGGSISSGLLSGRSDNHGGSEIVLTQSPATL

  SLSPGERATLSCRASQSVSSYLAWYQQKPGQAPRLLIYDASNRATGIPAR

  FSGSGSGTDFTLTISSLEPEDFAVYYCQQSSNWPRTFGQGTKVEIK

  [Spacer (SEQ ID NO: 918)]

  [NV1 NV04 2001 (SEQ ID NO: 1310)]

  Nucleotide Sequence:

  (SEQ ID NO: 1311)

  [CAAGGCCAGTCTGGCCAAGGT][AAGTGCTCGCGGCCTGCTCA

  TCAGAATCCGGATCGTTGCTCGCGAGGAGGTGGCTCGAGCGGCGGCTCTA

  TCTCTTCCGGACTGCTGTCCGGCAGATCCGACAATCACGGCGGATCCGAG

  ATCGTGCTGACACAGAGCCCTGCCACCCTGTCTCTGAGCCCTGGCGAAAG

  AGCCACCCTGAGCTGTAGAGCCAGCCAGAGCGTGTCCAGCTACCTGGCCT

  GGTATCAGCAGAAGCCCGGCCAGGCTCCCCGGCTGCTGATCTACGATGCC

  AGCAATAGAGCCACCGGCATCCCCGCCAGATTTTCCGGCTCTGGCAGCGG

  CACCGACTTCACCCTGACCATCAGCTCCCTGGAACCCGAGGACTTCGCCG

  TGTACTACTGCCAGCAGAGCAGCAACTGGCCCCGGACATTTGGCCAGGGC

  ACCAAGGTGGAAATCAAG]

  [Spacer (SEQ ID NO: 362)]

  [NV1 NV05 2001 (SEQ ID NO: 1312) Amino Acid Sequence:

  (SEQ ID NO: 1313)

  [QGQSGQG][ASYRCPDYKCSHTKHGGGSSGGSISSGLLSGRSD

  NHGGSEIVLTQSPATLSLSPGERATLSCRASQSVSSYLAWYQQKPGQAPR

  LLIYDASNRATGIPARFSGSGSGTDFTLTISSLEPEDFAVYYCQQSSNWP

  RTFGQGTKVEIK]

  NV1 NV05 2001 Amino Acid Sequence:

  (SEQ ID NO: 1312)

  ASYRCPDYKCSHTKHGGGSSGGSISSGLLSGRSDNHGGSEIVLTQSPATL

  SLSPGERATLSCRASQSVSSYLAWYQQKPGQAPRLLIYDASNRATGIPAR

  FSGSGSGTDFTLTISSLEPEDFAVYYCQQSSNWPRTFGQGTKVEIK

  [Spacer (SEQ ID NO: 918)]

  [NV1 NV05 2001 (SEQ ID NO: 1314)]

  Nucleotide Sequence:

  (SEQ ID NO: 1315)

  [CAAGGCCAGTCTGGCCAAGGT][GCTTCGTATCGGTGCCCTGA

  TTATAAGTGCAGTCATACTAAGCATGGAGGTGGCTCGAGCGGCGGCTCTA

  TCTCTTCCGGACTGCTGTCCGGCAGATCCGACAATCACGGCGGATCCGAG

  ATCGTGCTGACACAGAGCCCTGCCACCCTGTCTCTGAGCCCTGGCGAAAG

  AGCCACCCTGAGCTGTAGAGCCAGCCAGAGCGTGTCCAGCTACCTGGCCT

  GGTATCAGCAGAAGCCCGGCCAGGCTCCCCGGCTGCTGATCTACGATGCC

  AGCAATAGAGCCACCGGCATCCCCGCCAGATTTTCCGGCTCTGGCAGCGG

  CACCGACTTCACCCTGACCATCAGCTCCCTGGAACCCGAGGACTTCGCCG

  TGTACTACTGCCAGCAGAGCAGCAACTGGCCCCGGACATTTGGCCAGGGC

  ACCAAGGTGGAAATCAAG]

  [Spacer (SEQ ID NO: 362)]

  [NV1 NV06 2001 (SEQ ID NO: 1316) Amino Acid Sequence:

  (SEQ ID NO: 1317)

  [QGQSGQG][LPRCPDHPIKCIETKGGGSSGGSISSGLLSGRSD

  NHGGSEIVLTQSPATLSLSPGERATLSCRASQSVSSYLAWYQQKPGQAPR

  LLIYDASNRATGIPARFSGSGSGTDFTLTISSLEPEDFAVYYCQQSSNWP

  RTFGQGTKVEIK]

  NV1 NV06 2001 Amino Acid Sequence:

  (SEQ ID NO: 1316)

  LPRCPDHPIKCIETKGGGSSGGSISSGLLSGRSDNHGGSEIVLTQSPATL

  SLSPGERATLSCRASQSVSSYLAWYQQKPGQAPRLLIYDASNRATGIPAR

  FSGSGSGTDFTLTISSLEPEDFAVYYCQQSSNWPRTFGQGTKVEIK

  [Spacer (SEQ ID NO: 918)]

  [NV1 NV06 2001 (SEQ ID NO: 1318)]

  Nucleotide Sequence:

  (SEQ ID NO: 1319)

  [CAAGGCCAGTCTGGCCAAGGT][TTGCCGAGGTGCCCGGATCA

  TCCGATTAAGTGCATTGAGACTAAGGGAGGTGGCTCGAGCGGCGGCTCTA

  TCTCTTCCGGACTGCTGTCCGGCAGATCCGACAATCACGGCGGATCCGAG

  ATCGTGCTGACACAGAGCCCTGCCACCCTGTCTCTGAGCCCTGGCGAAAG

  AGCCACCCTGAGCTGTAGAGCCAGCCAGAGCGTGTCCAGCTACCTGGCCT

  GGTATCAGCAGAAGCCCGGCCAGGCTCCCCGGCTGCTGATCTACGATGCC

  AGCAATAGAGCCACCGGCATCCCCGCCAGATTTTCCGGCTCTGGCAGCGG

  CACCGACTTCACCCTGACCATCAGCTCCCTGGAACCCGAGGACTTCGCCG

  TGTACTACTGCCAGCAGAGCAGCAACTGGCCCCGGACATTTGGCCAGGGC

  ACCAAGGTGGAAATCAAG]

  [Spacer (SEQ ID NO: 362)]

  [NV1 NV07 2001 (SEQ ID NO: 1320) Amino Acid Sequence:

  (SEQ ID NO: 1321)

  [QGQSGQG][YTFGCPDRYCDRAATGGGSSGGSISSGLLSGRSDNHGGSE

  IVLTQSPATLSLSPGERATLSCRASQSVSSYLAWYQQKPGQAPRLLIYD

  ASNRATGIPARFSGSGSGTDFTLTISSLEPEDFAVYYCQQSSNWPRTFGQ

  GTKVEIK]

  NV1 NV07 2001 Amino Acid Sequence:

  (SEQ ID NO: 1320)

  YTFGCPDRYCDRAATGGGSSGGSISSGLLSGRSDNHGGSEIVLTQS

  PATLSLSPGERATLSCRASQSVSSYLAWYQQKPGQAPRLLIYDASNR

  ATGIPARFSGSGSGTDFTLTISSLEPEDFAVYYCQQSSNWPRTFGQG

  TKVEIK

  [Spacer (SEQ ID NO: 918)]

  [NV1 NV07 2001 (SEQ ID NO: 1322)]

  Nucleotide Sequence:

  (SEQ ID NO: 1323)

  [CAAGGCCAGTCTGGCCAAGGT][TATACGTTTGGTTGCCCTGATAGG

  TATTGCGATCGTGCGGCGACGGGAGGTGGCTCGAGCGGCGGCTCTATCT

  CTTCCGGACTGCTGTCCGGCAGATCCGACAATCACGGCGGATCCGAGAT

  CGTGCTGACACAGAGCCCTGCCACCCTGTCTCTGAGCCCTGGCGAAAGAG

  CCACCCTGAGCTGTAGAGCCAGCCAGAGCGTGTCCAGCTACCTGGCCTGG

  TATCAGCAGAAGCCCGGCCAGGCTCCCCGGCTGCTGATCTACGATGCCAG

  CAATAGAGCCACCGGCATCCCCGCCAGATTTTCCGGCTCTGGCAGCGGCA

  CCGACTTCACCCTGACCATCAGCTCCCTGGAACCCGAGGACTTCGCCGTG

  TACTACTGCCAGCAGAGCAGCAACTGGCCCCGGACATTTGGCCAGGGCAC

  CAAGGTGGAAATCAAG]

  [Spacer (SEQ ID NO: 362)]

  [NV1 NV08 2001 (SEQ ID NO: 1324) Amino Acid Sequence:

  (SEQ ID NO: 1325)

  [QGQSGQG][RGCPDFNPPSHCYTAGGGSSGGSISSGLLSGRSDNHGGSE

  IVLTQSPATLSLSPGERATLSCRASQSVSSYLAWYQQKPGQAPRLLIYDA

  SNRATGIPARFSGSGSGTDFTLTISSLEPEDFAVYYCQQSSNWPRTFGQG

  TKVEIK]

  NV1 NV08 2001 Amino Acid Sequence:

  (SEQ ID NO: 1324)

  RGCPDFNPPSHCYTAGGGSSGGSISSGLLSGRSDNHGGSEIVLTQSPA

  TLSLSPGERATLSCRASQSVSSYLAWYQQKPGQAPRLLIYDASNRATGI

  PARFSGSGSGTDFTLTISSLEPEDFAVYYCQQSSNWPRTFGQGTKVEIK

  [Spacer (SEQ ID NO: 918)]

  [NV1 NV08 2001 (SEQ ID NO: 1326)]

  Nucleotide Sequence:

  (SEQ ID NO: 1327)

  [CAAGGCCAGTCTGGCCAAGGT][CGTGGTTGTCCGGATTTTAATCCTCC

  TTCTCATTGCTATACTGCTGGAGGTGGCTCGAGCGGCGGCTCTATCTCTT

  CCGGACTGCTGTCCGGCAGATCCGACAATCACGGCGGATCCGAGATCGT

  GCTGACACAGAGCCCTGCCACCCTGTCTCTGAGCCCTGGCGAAAGAGCC

  ACCCTGAGCTGTAGAGCCAGCCAGAGCGTGTCCAGCTACCTGGCCTGGTA

  TCAGCAGAAGCCCGGCCAGGCTCCCCGGCTGCTGATCTACGATGCCAGC

  AATAGAGCCACCGGCATCCCCGCCAGATTTTCCGGCTCTGGCAGCGGCAC

  CGACTTCACCCTGACCATCAGCTCCCTGGAACCCGAGGACTTCGCCGTGT

  ACTACTGCCAGCAGAGCAGCAACTGGCCCCGGACATTTGGCCAGGGCAC

  CAAGGTGGAAATCAAG]

  [Spacer (SEQ ID NO: 362)]

  [NV1 NV09 2001 (SEQ ID NO: 1328) Amino Acid Sequence:

  (SEQ ID NO: 1329)

  [QGQSGQG][RDYCGPQSPDYCHEIGGGSSGGSISSGLLSGRSDNHGG

  SEIVLTQSPATLSLSPGERATLSCRASQSVSSYLAWYQQKPGQAPRLLIY

  DASNRATGIPARFSGSGSGTDFTLTISSLEPEDFAVYYCQQSSNWPRTFG

  QGTKVEIK]

  NV1 NV09 2001 Amino Acid Sequence:

  (SEQ ID NO: 1328)

  RDYCGPQSPDYCHEIGGGSSGGSISSGLLSGRSDNHGGSEIVLTQSPA

  TLSLSPGERATLSCRASQSVSSYLAWYQQKPGQAPRLLIYDASNRATGI

  PARFSGSGSGTDFTLTISSLEPEDFAVYYCQQSSNWPRTFGQGTKVEIK

  [Spacer (SEQ ID NO: 918)]

  [NV1 NV09 2001 (SEQ ID NO: 1330)]

  Nucleotide Sequence:

  (SEQ ID NO: 1331)

  [CAAGGCCAGTCTGGCCAAGGT][AGGGATTATTGCGGGCCTCAGAGTCC

  TGATTATTGCCATGAGATTGGAGGTGGCTCGAGCGGCGGCTCTATCTCTT

  CCGGACTGCTGTCCGGCAGATCCGACAATCACGGCGGATCCGAGATCGT

  GCTGACACAGAGCCCTGCCACCCTGTCTCTGAGCCCTGGCGAAAGAGCC

  ACCCTGAGCTGTAGAGCCAGCCAGAGCGTGTCCAGCTACCTGGCCTGGTA

  TCAGCAGAAGCCCGGCCAGGCTCCCCGGCTGCTGATCTACGATGCCAGCA

  ATAGAGCCACCGGCATCCCCGCCAGATTTTCCGGCTCTGGCAGCGGCACC

  GACTTCACCCTGACCATCAGCTCCCTGGAACCCGAGGACTTCGCCGTGTA

  CTACTGCCAGCAGAGCAGCAACTGGCCCCGGACATTTGGCCAGGGCACCA

  AGGTGGAAATCAAG]

  [Spacer (SEQ ID NO: 362)]

  [NV1 NV10 2001 (SEQ ID NO: 1332) Amino Acid Sequence:

  (SEQ ID NO: 1333)

  [QGQSGQG][PNKPCPDLQCYVTNYGGGSSGGSISSGLLSGRSDNHGG

  SEIVLTQSPATLSLSPGERATLSCRASQSVSSYLAWYQQKPGQAPRLLIY

  DASNRATGIPARFSGSGSGTDFTLTISSLEPEDFAVYYCQQSSNWPRTFG

  QGTKVEIK]

  NV1 NV10 2001 Amino Acid Sequence:

  (SEQ ID NO: 1332)

  PNKPCPDLQCYVTNYGGGSSGGSISSGLLSGRSDNHGGSEIVLTQSPA

  TLSLSPGERATLSCRASQSVSSYLAWYQQKPGQAPRLLIYDASNRATGI

  PARFSGSGSGTDFTLTISSLEPEDFAVYYCQQSSNWPRTFGQGTKVEIK

  [Spacer (SEQ ID NO: 918)]

  [NV1 NV10 2001 (SEQ ID NO: 1334)]

  Nucleotide Sequence:

  (SEQ ID NO: 1335)

  [CAAGGCCAGTCTGGCCAAGGT][CCGAATAAGCCTTGCCCGGATCTGC

  AGTGCTATGTGACGAATTATGGAGGTGGCTCGAGCGGCGGCTCTATCTCT

  TCCGGACTGCTGTCCGGCAGATCCGACAATCACGGCGGATCCGAGATCG

  TGCTGACACAGAGCCCTGCCACCCTGTCTCTGAGCCCTGGCGAAAGAGCC

  ACCCTGAGCTGTAGAGCCAGCCAGAGCGTGTCCAGCTACCTGGCCTGGTA

  TCAGCAGAAGCCCGGCCAGGCTCCCCGGCTGCTGATCTACGATGCCAGC

  AATAGAGCCACCGGCATCCCCGCCAGATTTTCCGGCTCTGGCAGCGGCAC

  CGACTTCACCCTGACCATCAGCTCCCTGGAACCCGAGGACTTCGCCGTGT

  ACTACTGCCAGCAGAGCAGCAACTGGCCCCGGACATTTGGCCAGGGCACC

  AAGGTGGAAATCAAG]

  [Spacer (SEQ ID NO: 362)]

  [NV1 NV11 2001 (SEQ ID NO: 1336) Amino Acid Sequence:

  (SEQ ID NO: 1337)

  [QGQSGQG][PRVACGEPDLCYSNTGGGSSGGSISSGLLSGRSDNHGG

  SEIVLTQSPATLSLSPGERATLSCRASQSVSSYLAWYQQKPGQAPRLLIY

  DASNRATGIPARFSGSGSGTDFTLTISSLEPEDFAVYYCQQSSNWPRTF

  GQGTKVEIK]

  NV1 NV11 2001 Amino Acid Sequence:

  (SEQ ID NO: 1336)

  PRVACGEPDLCYSNTGGGSSGGSISSGLLSGRSDNHGGSEIVLTQSPA

  TLSLSPGERATLSCRASQSVSSYLAWYQQKPGQAPRLLIYDASNRATGI

  PARFSGSGSGTDFTLTISSLEPEDFAVYYCQQSSNWPRTFGQGTKVEIK

  [Spacer (SEQ ID NO: 918)]

  [NV1 NV11 2001 (SEQ ID NO: 1338)]

  Nucleotide Sequence:

  (SEQ ID NO: 1339)

  [CAAGGCCAGTCTGGCCAAGGT][CCGCGGGTTGCTTGCGGTGAGCCT

  GATCTTTGCTATTCTAATACTGGAGGTGGCTCGAGCGGCGGCTCTATCTC

  TTCCGGACTGCTGTCCGGCAGATCCGACAATCACGGCGGATCCGAGATC

  GTGCTGACACAGAGCCCTGCCACCCTGTCTCTGAGCCCTGGCGAAAGAGC

  CACCCTGAGCTGTAGAGCCAGCCAGAGCGTGTCCAGCTACCTGGCCTGGT

  ATCAGCAGAAGCCCGGCCAGGCTCCCCGGCTGCTGATCTACGATGCCAGC

  AATAGAGCCACCGGCATCCCCGCCAGATTTTCCGGCTCTGGCAGCGGCAC

  CGACTTCACCCTGACCATCAGCTCCCTGGAACCCGAGGACTTCGCCGTGT

  ACTACTGCCAGCAGAGCAGCAACTGGCCCCGGACATTTGGCCAGGGCAC

  CAAGGTGGAAATCAAG]

  [Spacer (SEQ ID NO: 362)]

  [NV1 NV12 2001 (SEQ ID NO: 1340) Amino Acid Sequence:

  (SEQ ID NO: 1341)

  [QGQSGQG][RGCKKHTISTLTCPDGGGSSGGSISSGLLSGRSDNHGG

  SEIVLTQSPATLSLSPGERATLSCRASQSVSSYLAWYQQKPGQAPRLLIY

  DASNRATGIPARFSGSGSGTDFTLTISSLEPEDFAVYYCQQSSNWPRTFG

  QGTKVEIK]

  NV1 NV12 2001 Amino Acid Sequence:

  (SEQ ID NO: 1340)

  RGCKKHTISTLTCPDGGGSSGGSISSGLLSGRSDNHGGSEIVLTQSPATL

  SLSPGERATLSCRASQSVSSYLAWYQQKPGQAPRLLIYDASNRATGIPAR

  FSGSGSGTDFTLTISSLEPEDFAVYYCQQSSNWPRTFGQGTKVEIK

  [Spacer (SEQ ID NO: 918)]

  [NV1 NV12 2001 (SEQ ID NO: 1342)]

  Nucleotide Sequence:

  (SEQ ID NO: 1343)

  [CAAGGCCAGTCTGGCCAAGGT][CGGGGGTGCAAGAAGCATACTATT

  TCGACGCTTACGTGCCCTGATGGAGGTGGCTCGAGCGGCGGCTCTA

  TCTCTTCCGGACTGCTGTCCGGCAGATCCGACAATCACGGCGGATCCGAG

  ATCGTGCTGACACAGAGCCCTGCCACCCTGTCTCTGAGCCCTGGCGAAAG

  AGCCACCCTGAGCTGTAGAGCCAGCCAGAGCGTGTCCAGCTACCTGGCCT

  GGTATCAGCAGAAGCCCGGCCAGGCTCCCCGGCTGCTGATCTACGATGCC

  AGCAATAGAGCCACCGGCATCCCCGCCAGATTTTCCGGCTCTGGCAGCGG

  CACCGACTTCACCCTGACCATCAGCTCCCTGGAACCCGAGGACTTCGCCG

  TGTACTACTGCCAGCAGAGCAGCAACTGGCCCCGGACATTTGGCCAGGGC

  ACCAAGGTGGAAATCAAG]

  Human Kappa Constant

  (SEQ ID NO: 1344)

  RTVAAPSVFIFPPSDEQLKSGTASVVCLLNNFYPREAKVQWKVDNALQSG

  NSQESVTEQDSKDSTYSLSSTLTLSKADYEKHKVYACEVTHQGLSSPVTK

  SFNRGEC

  Human Kappa Constant

  (SEQ ID NO: 1345)

  CGTACGGTGGCTGCACCATCTGTCTTCATCTTCCCGCCATCTGATGAGCA

  GTTGAAATCTGGAACTGCCTCTGTTGTGTGCCTGCTGAATAACTTCTATC

  CCAGAGAGGCCAAAGTACAGTGGAAGGTGGATAACGCCCTCCAATCGGGT

  AACTCCCAGGAGAGTGTCACAGAGCAGGACAGCAAGGACAGCACCTACAG

  CCTCAGCAGCACCCTGACGCTGAGCAAAGCAGACTACGAGAAACACAAAG

  TCTACGCCTGCGAAGTCACCCATCAGGGCCTGAGCTCGCCCGTCACAAAG

  AGCTTCAACAGGGGAGAGTGT

  NV1 HC Variable

  (SEQ ID NO: 1346)

  QVQLVESGGGVVQPGRSLRLDCKASGITFSNSGMHWVRQAPGKGLEWVAV

  IWYDGSKRYYADSVKGRFTISRDNSKNTLFLQMNSLRAEDTAVYYCATND

  DYWGQGTLVTVSS

  NV1 HC Variable

  (SEQ ID NO: 1347)

  CAGGTGCAGCTGGTGGAATCTGGCGGCGGAGTGGTGCAGCCTGGCAGAAG

  CCTGAGACTGGACTGCAAGGCCAGCGGCATCACCTTCAGCAACAGCGGCA

  TGCACTGGGTGCGCCAGGCCCCTGGAAAAGGCCTGGAATGGGTGGCCGTG

  ATTTGGTACGACGGCAGCAAGCGGTACTACGCCGACAGCGTGAAGGGCCG

  GTTCACCATCAGCCGGGACAACAGCAAGAATACCCTGTTCCTGCAGATGA

  ACAGCCTGCGGGCCGAGGACACCGCCGTGTACTACTGCGCCACCAACGAC

  GACTATTGGGGCCAGGGCACACTCGTGACCGTGTCCTCT

  hIgG4 S228P Constant

  (SEQ ID NO: 1348)

  ASTKGPSVFPLAPCSRSTSESTAALGCLVKDYFPEPVTVSWNSGALTSGV

  HTFPAVLQSSGLYSLSSVVTVPSSSLGTKTYTCNVDHKPSNTKVDKRVES

  KYGPPCPPCPAPEFLGGPSVFLFPPKPKDTLMISRTPEVTCVVVDVSQED

  PEVQFNWYVDGVEVHNAKTKPREEQFNSTYRVVSVLTVLHQDWLNGKEYK

  CKVSNKGLPSSIEKTISKAKGQPREPQVYTLPPSQEEMTKNQVSLTCLVK

  GFYPSDIAVEWESNGQPENNYKTTPPVLDSDGSFFLYSRLTVDKSRWQEG

  NVFSCSVMHEALHNHYTQKSLSLSLGK

  hIgG4 S228P Constant

  (SEQ ID NO: 1349)

  GCTAGCACCAAGGGCCCATCGGTCTTCCCCCTGGCACCCTGTAGCAGAAG

  CACCAGCGAGTCTACAGCGGCCCTGGGCTGCCTGGTCAAGGACTACTTCC

  CCGAACCGGTGACGGTGTCGTGGAACTCAGGCGCCCTGACCAGCGGCGTG

  CACACCTTCCCGGCTGTCCTACAGTCCTCAGGACTCTACTCCCTCAGCAG

  CGTGGTGACCGTGCCCTCCAGCAGCTTGGGCACCAAGACCTACACCTGTA

  ACGTGGACCACAAGCCCAGCAACACCAAGGTGGACAAGCGGGTGGAATCT

  AAGTACGGCCCTCCCTGCCCTCCTTGCCCAGCCCCTGAATTTCTGGGGGG

  ACCGTCAGTCTTCCTCTTCCCCCCAAAACCCAAGGACACCCTCATGATCT

  CCCGGACCCCTGAGGTCACATGCGTGGTGGTGGACGTGAGCCAGGAAGAC

  CCTGAGGTCCAGTTCAACTGGTACGTGGACGGCGTGGAGGTGCATAATGC

  CAAGACAAAGCCGCGGGAGGAGCAGTTCAACAGCACGTACCGTGTGGTCA

  GCGTCCTCACCGTCCTGCACCAGGACTGGCTGAATGGCAAGGAGTACAAG

  TGCAAGGTCTCCAACAAAGGCCTGCCCAGCTCCATCGAGAAAACCATCTC

  CAAAGCCAAAGGGCAGCCCCGAGAACCACAGGTGTACACCCTGCCCCCAT

  CCCAGGAGGAGATGACCAAGAACCAGGTCAGCCTGACCTGCCTGGTCAAA

  GGCTTCTATCCCAGCGACATCGCCGTGGAGTGGGAGAGCAATGGGCAGCC

  GGAGAACAACTACAAGACCACGCCTCCCGTGCTGGACTCCGACGGCTCCT

  TCTTCCTCTACAGCAGACTCACCGTGGACAAGAGCAGGTGGCAGGAAGGG

  AACGTCTTCTCATGCTCCGTGATGCATGAGGCTCTGCACAACCACTACAC

  GCAGAAGAGCCTCTCCCTGTCTCTGGGTAAA

Example 21: Characterization of Activatable Anti-PD1 NV1 Antibodies
• This example describes activatable anti-PD1 NV1 antibodies with reduced binding to hPD1.
• Masking efficiencies were evaluated by standard plate ELISA. Briefly, human PD1-Fc (R and D systems, Minneapolis, Minn.) was adsorbed to the wells of a 96-well ELISA plate. Purified NV1 and activatable NV1 antibodies were applied to the plate in serial dilution and allowed to bind. Bound antibody and activatable antibodies were detected with anti-hu Fab-HRP conjugate (Sigma, St Louis, Mo.) and visualized with the chromogenic substrate TMB (Thermo Scientific, Rockford, Ill.). Plots were generated in Prizm (Sigma Plot). All activatable NV1 antibodies showed decreased binding compared with the parental NV1, as shown in FIG. 26.
Example 22: Activatable Anti-PD1 Pembrolizumab Masking Moieties
• This example describes identification of masking moieties (MM) that reduce binding of anti-PD1 pembrolizumab antibody to its target.
• Anti-PD1 Pembrolizumab (PM1) (see, e.g., U.S. Pat. No. 8,354,509) was used to screen libraries using a method similar to that described in PCT International Publication Number WO 2010/081173, published 15 Jul. 2010. The screening consisted of one round of MACS and three rounds of FACS sorting. For the initial MACS, approximately 1.6×10¹² cells were incubated with PM1 antibody at a concentration of 200 nM, and approximately 8×10⁶ binders were collected using Protein-A Dynabeads (Life Technologies, Carlsbad, Calif.). FACS rounds were conducted labeling cells with DyLight 650 (Thermo-Fisher) labeled PM1 antibody and collecting cells with strongest fluorescence as follows: 100 nM PM1-650 collecting brightest 10% for FACS round 1 (5.6×10⁵ for F1), 10 nM PM1-650 collecting brightest 1.5% for FACS round 2 (1.4×10⁴ for F2), 1 nM PM1-650 collecting all binders above background (4,000) and the top 0.2% (820) for FACS round 3 (F3). Individual peptide clones from the two F3 populations were identified by sequence analysis (Table 20), and selected peptide clones PM01-PM12 were subsequently verified for their ability to bind PM1 (masking moiety PM001 is also referred to herein as PM01 and/or PM-01; masking moiety PM002 is also referred to herein as PM02 and/or PM-02, and so on).

• TABLE 20
  	Mask	Amino Acid Sequence	SEQ ID NO:
  	PM01	GCDFTSAKHNCGSGW	1351
  	PM02	VGSNCWTGPACALTS	1352
  	PM03	FCAVMFDFLSDRCLH	1353
  	PM04	FCPPWLDYLGNKCMT	1354
  	PM05	MSCWDFSSAQGCGQH	1355
  	PM06	LMCADLHYNHYNCKY	1356
  	PM07	ELCGWQSFSGVCTSE	1357
  	PM08	WTYENCWASCQPHLE	1358
  	PM09	KLTEDFSSAA	1359
  	PM10	VGQSCFSGLVCDRQL	1360
  	PM11	ISHYCFSGKSCRD	1361
  	PM12	HCIPDFTSAAGDCMR	1362
  	PM13	RLVSAYSFS	1363
  	PM14	KFHHSHPLVHDFTSA	1364
  	PM15	ASYPDFSSANGVGLR	1365
  	PM16	GLATTLSNVDFTSAG	1366
  	PM17	DFTSANSAFSGDAST	1367
  	PM18	GRLPGHSVVDFTSAW	1368
  	PM19	SGSFYSSSAFDFTSA	1369
  	PM20	CDDFTSAQHSRINEC	1370
  	PM21	CDFTSAQGKKCRTAL	1371
  	PM22	YYIDKYQSPSYGPVL	1372
  	PM23	FSVARARSSADFTSS	1373
  	PM24	DSDFTSAGSADSRSR	1374
  	PM25	CDFTSATSISKRCDH	1375
  	PM26	IESSASSWGLQASRN	1376
  	PM27	PRYHNLNFTTPALSPGS	1377
  	PM28	DLFARFPLDRDFTSA	1378
  	PM29	HCNFTTPPYCSSTLW	1379
  	PM30	NVPIILLTDRQLLSG	1380
  	PM31	NPTACDFTSSMATYC	1381
  	PM32	FVRTVRFSNSMFSVP	1382
  	PM33	YDFSSASNSSPSRQT	1383
  	PM34	AHPDFSSAMRGNLLG	1384
  	PM35	SSHVVHKDFTSANSR	1385
  	PM36	CPDFTSANGGGCWQM	1386
  	PM37	SLGQSYPTDFTCPGC	1387
  	PM38	ASMRSHEQRDFTSAY	1388
  	PM39	SCQFWFTLCSGGVFH	1389
  	PM40	PYPNNRTGMHDFTSA	1390
  	PM41	KPFPIDFTSAGTSGT	1391
  	PM42	SIKSFIPRDDFTSAA	1392
  	PM43	GIKNPATPFVDFTSA	1393
  	PM44	LSHTYPRGSSTIEAS	1394
  	PM45	PSLDFSSAT	1395
  	PM46	AFTPRIAPTFDVMKE	1396
  	PM47	LCGLQIPPDCERS	1397
  	PM48	AAKMVSHSERDFTSA	1398
  	PM49	VSVECFSGMQCPHYY	1399
  	PM50	ASKCRLPCMASTQIY	1400
  	PM51	GLRSCNIYFSIPCTY	1401
  	PM52	RGTSDGTLDFTTARS	1402
  	PM53	SMYPSASRLLHPQYP	1403
  	PM54	HCISCYDFTSAAGSF	1404
  	PM55	SSGRWGDAWACARIC	1405
  	PM56	RVFSDFTSASHSFGG	1406
  	PM57	TDRHSASGRDFTSAH	1407
  	PM58	AHCEDFSSAERIATMGC	1408
  	PM59	ACDPYSFSIPCDDRL	1409
  	PM60	NSPFTLSHIYDR	1410
  	PM61	IGTNFTTPSAFVAFP	1411
  	PM62	RDAFPIYRNADFSTP	1412
  	PM63	SIPNASSYNFTSSSG	1413
  	PM64	AGIPDKRHTYDFTSA	1414
  	PM65	WPLAHDSRDWNFTTP	1415
  	PM66	RHSPSSGHVDFTSAG	1416
  	PM67	SCFAWTDPVWNRCSW	1417
  	PM68	MPCDWTGPGKIWCGG	1418
  	PM69	RDCDFSTANFRSCNK	1419
  	PM70	LSCVVSPNYLHCNDH	1420
  	PM71	FVCGLYSFSGVCQGV	1421
  	PM72	IGLMCFSGLQCPMLA	1422
  	PM73	PGMNCFSGEICQMST	1423
  	PM74	GDVGSCWASCGLQGG	1424
  	PM75	SQFQDCWASCGASFT	1425
  	PM76	VGSLNCWYSCGDIWL	1426
  	PM77	MCESWLNFLGDQCGM	1427
  	PM78	RCMISQSSFSGMCGM	1428
  	PM79	NCAPWTSNMSNHCLK	1429
  	PM80	LCGVGSATGLELCGV	1430
  	PM81	GCDFSSLGGRQPCTP	1431
  	PM82	MGCNFTTYPYHTCNT	1432
  	PM83	GSCDFTSGAGKKCGS	1433
  	PM84	VSCDFTSSHARMCSR	1434
  	PM85	MRCTDFYYNHTNCIG	1435
  	PM86	RSCDFTSAANKYCAT	1436
  	PM87	LYCDSFSVPRPNCAP	1437
  	PM88	NSCDFTSARVSKCST	1438
  	PM89	STCSDNFTTPMPCNT	1439
  	PM90	DICNDRPNLTHCHYF	1440
  	PM91	LRCDDFTSAIGCRGY	1441
  	PM92	EGCDFTSALHSCNNY	1442
  	PM93	RKGCGDFTSASCFVV	1443
  	PM94	GMLCAGSSFGLCESM	1444
  	PM95	RESCFGSSLGLCTNK	1445
  	PM96	ILRCYDIPTNCMNFN	1446
  	PM97	NSECTFGAMYCRNKP	1447
  	PM98	ASGCFDEDIRCSGGA	1448
  	PM99	HYFCNQSNPSCQTAP	1449
  	PM100	AMGCELGGAGCIGSP	1450
  	PM101	TLKCHMPRKLCANDP	1451
  	PM102	RPACRDLPHNCITST	1452
  	PM103	QMSCHGNFTTCHSNP	1453
  	PM104	LTGCARGARPCRLRV	1454
  	PM105	WSELCLAGPSCGWVG	1455
  	PM106	VTKSCWQLPHCITAP	1456
  	PM107	KAASCPHNQICNMTA	1457
  	PM108	VSKNCFSGMMCPVFA	1458
  	PM109	NRSSCWTGPTCHVLH	1459
  	PM110	ARTGCSGPVCLNDVS	1460
  	PM111	STRTCLAFTCINGNT	1461
  	PM112	MLDGNCWYACSYKNT	1462
  	PM113	FSRSDCWSACAPWRV	1463
  	PM114	GGRMDCWASCQPLSR	1464
  	PM115	NSPHSCMTNCDFTSA	1465

Example 23: Activatable Anti-PD1 Pembrolizumab Antibodies
• This example describes examples of activatable anti-PD1 Pembrolizumab antibodies of the disclosure.
• Activatable anti-PD1 PM1 antibodies comprising an anti-PD1 PM1 masking moiety, a cleavable moiety, and an anti-PD1 PM1 antibody of the disclosure were produced according to methods similar to those described in PCT Publication Nos. WO 2009/025846 and WO 2010/081173. One embodiment of the disclosure is an anti-PD-1 activatable antibody comprising a heavy chain comprising amino acid sequence SEQ ID NO: 1514. One embodiment of the disclosure is an anti-PD-1 activatable antibody comprising a light chain comprising amino acid sequence SEQ ID NO: 638. One embodiment of the disclosure is an anti-PD-1 activatable antibody comprising a heavy chain comprising amino acid sequence SEQ ID NO: 1514 and a light chain comprising amino acid sequence SEQ ID NO: 638. One embodiment of the disclosure is an anti-PD-1 activatable antibody comprising the CDRs of an anti-PD-1 activatable antibody comprising a heavy chain comprising amino acid sequence SEQ ID NO: 1514 and a light chain comprising amino acid sequence SEQ ID NO: 638.
• The amino acid and nucleic acid sequences of several activatable anti-PD1 antibody variable domains of the disclosure are provided below. Antibodies were produced as hIgG4 containing a single amino acid substitution, S228P (Angal, et al. 1993. Mol Immunol 30:105-8.) HC and hK LC format.

• PM1 Light Chain Amino Acid Sequence:

  (SEQ ID NO: 638)

  EIVLTQSPATLSLSPGERATLSCRASKGVSTSGYSYLHWYQQKPGQAPRL

  LIYLASYLESGVPARFSGSGSGTDFTLTISSLEPEDFAVYYCQHSRDLPL

  TFGGGTKVEIK

  [Spacer (SEQ ID NO: 362)]

  [PM1 PM01 2001 (SEQ ID NO: 1466)]

  Amino Acid Sequence:

  (SEQ ID NO: 1467)

  [QGQSGQG][CDFTSAKHNCGSGWGSSGGSISSGLLSGRSDNHGGSEI

  VLTQSPATLSLSPGERATLSCRASKGVSTSGYSYLHWYQQKPGQAPRLLI

  YLASYLESGVPARFSGSGSGTDFTLTISSLEPEDFAVYYCQHSRDLPLTF

  GGGTKVEIK]

  PM1 PM01 2001 Amino Acid Sequence:

  (SEQ ID NO: 1466)

  CDFTSAKHNCGSGWGSSGGSISSGLLSGRSDNHGGSEIVLTQSPATLSLS

  PGERATLSCRASKGVSTSGYSYLHWYQQKPGQAPRLLIYLASYLESGVPA

  RFSGSGSGTDFTLTISSLEPEDFAVYYCQHSRDLPLTFGGGTKVEIK

  [Spacer (SEQ ID NO: 1126)]

  [PM1 PM01 2001 (SEQ ID NO: 1468)]

  Nucleotide Sequence:

  (SEQ ID NO: 1469)

  [CAAGGCCAGTCTGGCCAAGGA][TGCGATTTTACTTCTGCCAAGCAC

  AATTGCGGCTCTGGCTGGGGCTCGAGCGGCGGCTCTATCTCTTCCGGACT

  GCTGTCCGGCAGATCCGACAATCACGGCGGATCCGAGATCGTGCTGACAC

  AGAGCCCTGCCACCCTGTCTCTGAGCCCTGGCGAAAGAGCCACCCTGAGC

  TGTAGAGCCTCTAAGGGCGTGTCCACCAGCGGCTACAGCTACCTGCACTG

  GTATCAGCAGAAGCCCGGCCAGGCCCCCAGACTGCTGATCTACCTGGCCT

  CCTACCTGGAAAGCGGCGTGCCCGCCAGATTTTCTGGCTCTGGCAGCGGC

  ACCGACTTCACCCTGACAATCAGCAGCCTGGAACCCGAGGACTTCGCCGT

  GTACTACTGCCAGCACAGCAGGGACCTGCCCCTGACATTTGGCGGAGGCA

  CCAAGGTGGAAATCAAG]

  [Spacer (SEQ ID NO: 362)]

  [PM1 PM02 2001 (SEQ ID NO: 1470)]

  Amino Acid Sequence:

  (SEQ ID NO: 1471)

  [QGQSGQG][VGSNCWTGPACALTSGGGSSGGSISSGLLSGRSDNHGG

  SEIVLTQSPATLSLSPGERATLSCRASKGVSTSGYSYLHWYQQKPGQAPR

  LLIYLASYLESGVPARFSGSGSGTDFTLTISSLEPEDFAVYYCQHSRDLP

  LTFGGGTKVEIK]

  PM1 PM02 2001 Amino Acid Sequence:

  (SEQ ID NO: 1470)

  VGSNCWTGPACALTSGGGSSGGSISSGLLSGRSDNHGGSEIVLTQSPATL

  SLSPGERATLSCRASKGVSTSGYSYLHWYQQKPGQAPRLLIYLASYLESG

  VPARFSGSGSGTDFTLTISSLEPEDFAVYYCQHSRDLPLTFGGGTKVEIK

  [Spacer (SEQ ID NO: 918)]

  [PM1 PM02 2001 (SEQ ID NO: 1472)]

  Nucleotide Sequence:

  (SEQ ID NO: 1473)

  [CAAGGCCAGTCTGGCCAAGGT][GTTGGGTCGAATTGCTGGACGGGGCC

  GGCGTGCGCTTTGACGTCGGGAGGTGGCTCGAGCGGCGGCTCTATCTCTT

  CCGGACTGCTGTCCGGCAGATCCGACAATCACGGCGGATCCGAGATCGTG

  CTGACACAGAGCCCTGCCACCCTGTCTCTGAGCCCTGGCGAAAGAGCCAC

  CCTGAGCTGTAGAGCCTCTAAGGGCGTGTCCACCAGCGGCTACAGCTACC

  TGCACTGGTATCAGCAGAAGCCCGGCCAGGCCCCCAGACTGCTGATCTAC

  CTGGCCTCCTACCTGGAAAGCGGCGTGCCCGCCAGATTTTCTGGCTCTGG

  CAGCGGCACCGACTTCACCCTGACAATCAGCAGCCTGGAACCCGAGGACT

  TCGCCGTGTACTACTGCCAGCACAGCAGGGACCTGCCCCTGACATTTGGC

  GGAGGCACCAAGGTGGAAATCAAG]

  [Spacer (SEQ ID NO: 362)]

  [PM1 PM03 2001 (SEQ ID NO: 1474)]

  Amino Acid Sequence:

  (SEQ ID NO: 1475)

  [QGQSGQG][FCAVMFDFLSDRCLHGGGSSGGSISSGLLSGRSDNHGGSE

  IVLTQSPATLSLSPGERATLSCRASKGVSTSGYSYLHWYQQKPGQAPRLL

  IYLASYLESGVPARFSGSGSGTDFTLTISSLEPEDFAVYYCQHSRDLPLT

  FGGGTKVEIK]

  PM1 PM03 2001 Amino Acid Sequence:

  (SEQ ID NO: 1474)

  FCAVMFDFLSDRCLHGGGSSGGSISSGLLSGRSDNHGGSEIVLTQSPATL

  SLSPGERATLSCRASKGVSTSGYSYLHWYQQKPGQAPRLLIYLASYLESG

  VPARFSGSGSGTDFTLTISSLEPEDFAVYYCQHSRDLPLTFGGGTKVEIK

  [Spacer (SEQ ID NO: 918)]

  [PM1 PM03 2001 (SEQ ID NO: 1476)]

  Nucleotide Sequence:

  (SEQ ID NO: 1477)

  [CAAGGCCAGTCTGGCCAAGGT][TTTTGCGCTGTGATGTTTGATTTTCT

  GTCTGATCGGTGCCTGCATGGAGGTGGCTCGAGCGGCGGCTCTATCTCTT

  CCGGACTGCTGTCCGGCAGATCCGACAATCACGGCGGATCCGAGATCGTG

  CTGACACAGAGCCCTGCCACCCTGTCTCTGAGCCCTGGCGAAAGAGCCAC

  CCTGAGCTGTAGAGCCTCTAAGGGCGTGTCCACCAGCGGCTACAGCTACC

  TGCACTGGTATCAGCAGAAGCCCGGCCAGGCCCCCAGACTGCTGATCTAC

  CTGGCCTCCTACCTGGAAAGCGGCGTGCCCGCCAGATTTTCTGGCTCTGG

  CAGCGGCACCGACTTCACCCTGACAATCAGCAGCCTGGAACCCGAGGACT

  TCGCCGTGTACTACTGCCAGCACAGCAGGGACCTGCCCCTGACATTTGGC

  GGAGGCACCAAGGTGGAAATCAAG]

  [Spacer (SEQ ID NO: 362)]

  [PM1 PM04 2001 (SEQ ID NO: 1478)]

  Amino Acid Sequence:

  (SEQ ID NO: 1479)

  [QGQSGQG][FCPPWLDYLGNKCMTGGGSSGGSISSGLLSGRSDNHGGSE

  IVLTQSPATLSLSPGERATLSCRASKGVSTSGYSYLHWYQQKPGQAPRLL

  IYLASYLESGVPARFSGSGSGTDFTLTISSLEPEDFAVYYCQHSRDLPLT

  FGGGTKVEIK]

  PM1 PM04 2001 Amino Acid Sequence:

  (SEQ ID NO: 1478)

  FCPPWLDYLGNKCMTGGGSSGGSISSGLLSGRSDNHGGSEIVLTQSPATL

  SLSPGERATLSCRASKGVSTSGYSYLHWYQQKPGQAPRLLIYLASYLESG

  VPARFSGSGSGTDFTLTISSLEPEDFAVYYCQHSRDLPLTFGGGTKVEIK

  [Spacer (SEQ ID NO: 918)]

  [PM1 PM04 2001 (SEQ ID NO: 1480)]

  Nucleotide Sequence:

  (SEQ ID NO: 1481)

  [CAAGGCCAGTCTGGCCAAGGT][TTTTGCCCGCCGTGGTTGGATTATTT

  GGGTAATAAGTGCATGACGGGAGGTGGCTCGAGCGGCGGCTCTATCTCTT

  CCGGACTGCTGTCCGGCAGATCCGACAATCACGGCGGATCCGAGATCGTG

  CTGACACAGAGCCCTGCCACCCTGTCTCTGAGCCCTGGCGAAAGAGCCAC

  CCTGAGCTGTAGAGCCTCTAAGGGCGTGTCCACCAGCGGCTACAGCTACC

  TGCACTGGTATCAGCAGAAGCCCGGCCAGGCCCCCAGACTGCTGATCTAC

  CTGGCCTCCTACCTGGAAAGCGGCGTGCCCGCCAGATTTTCTGGCTCTGG

  CAGCGGCACCGACTTCACCCTGACAATCAGCAGCCTGGAACCCGAGGACT

  TCGCCGTGTACTACTGCCAGCACAGCAGGGACCTGCCCCTGACATTTGGC

  GGAGGCACCAAGGTGGAAATCAAG]

  [Spacer (SEQ ID NO: 362)]

  [PM1 PM05 2001 (SEQ ID NO: 1482)]

  Amino Acid Sequence:

  (SEQ ID NO: 1483)

  [QGQSGQG][MSCWDFSSAQGCGQHGGGSSGGSISSGLLSGRSDNHGGSE

  IVLTQSPATLSLSPGERATLSCRASKGVSTSGYSYLHWYQQKPGQAPRLL

  IYLASYLESGVPARFSGSGSGTDFTLTISSLEPEDFAVYYCQHSRDLPLT

  FGGGTKVEIK]

  PM1 PM05 2001 Amino Acid Sequence:

  (SEQ ID NO: 1482)

  MSCWDFSSAQGCGQHGGGSSGGSISSGLLSGRSDNHGGSEIVLTQSPATL

  SLSPGERATLSCRASKGVSTSGYSYLHWYQQKPGQAPRLLIYLASYLESG

  VPARFSGSGSGTDFTLTISSLEPEDFAVYYCQHSRDLPLTFGGGTKVEIK

  [Spacer (SEQ ID NO: 918)]

  [PM1 PM05 2001 (SEQ ID NO: 1484)]

  Nucleotide Sequence:

  (SEQ ID NO: 1485)

  [CAAGGCCAGTCTGGCCAAGGT][ATGTCTTGCTGGGATTTTTCTTCGGC

  TCAGGGGTGCGGTCAGCATGGAGGTGGCTCGAGCGGCGGCTCTATCTCTT

  CCGGACTGCTGTCCGGCAGATCCGACAATCACGGCGGATCCGAGATCGTG

  CTGACACAGAGCCCTGCCACCCTGTCTCTGAGCCCTGGCGAAAGAGCCAC

  CCTGAGCTGTAGAGCCTCTAAGGGCGTGTCCACCAGCGGCTACAGCTACC

  TGCACTGGTATCAGCAGAAGCCCGGCCAGGCCCCCAGACTGCTGATCTAC

  CTGGCCTCCTACCTGGAAAGCGGCGTGCCCGCCAGATTTTCTGGCTCTGG

  CAGCGGCACCGACTTCACCCTGACAATCAGCAGCCTGGAACCCGAGGACT

  TCGCCGTGTACTACTGCCAGCACAGCAGGGACCTGCCCCTGACATTTGGC

  GGAGGCACCAAGGTGGAAATCAAG]

  [Spacer (SEQ ID NO: 362)]

  [PM1 PM06 2001 (SEQ ID NO: 1486)]

  Amino Acid Sequence:

  (SEQ ID NO: 1487)

  [QGQSGQG][LMCADLHYNHYNCKYGGGSSGGSISSGLLSGRSDNHGGSE

  IVLTQSPATLSLSPGERATLSCRASKGVSTSGYSYLHWYQQKPGQAPRLL

  IYLASYLESGVPARFSGSGSGTDFTLTISSLEPEDFAVYYCQHSRDLPLT

  FGGGTKVEIK]

  PM1 PM06 2001 Amino Acid Sequence:

  (SEQ ID NO: 1486)

  LMCADLHYNHYNCKYGGGSSGGSISSGLLSGRSDNHGGSEIVLTQSPATL

  SLSPGERATLSCRASKGVSTSGYSYLHWYQQKPGQAPRLLIYLASYLESG

  VPARFSGSGSGTDFTLTISSLEPEDFAVYYCQHSRDLPLTFGGGTKVEIK

  [Spacer (SEQ ID NO: 918)]

  [PM1 PM06 2001 (SEQ ID NO: 1488)]

  Nucleotide Sequence:

  (SEQ ID NO: 1489)

  [CAAGGCCAGTCTGGCCAAGGT][TTGATGTGCGCTGATTTGCATTATAA

  TCATTATAATTGCAAGTATGGAGGTGGCTCGAGCGGCGGCTCTATCTCTT

  CCGGACTGCTGTCCGGCAGATCCGACAATCACGGCGGATCCGAGATCGTG

  CTGACACAGAGCCCTGCCACCCTGTCTCTGAGCCCTGGCGAAAGAGCCAC

  CCTGAGCTGTAGAGCCTCTAAGGGCGTGTCCACCAGCGGCTACAGCTACC

  TGCACTGGTATCAGCAGAAGCCCGGCCAGGCCCCCAGACTGCTGATCTAC

  CTGGCCTCCTACCTGGAAAGCGGCGTGCCCGCCAGATTTTCTGGCTCTGG

  CAGCGGCACCGACTTCACCCTGACAATCAGCAGCCTGGAACCCGAGGACT

  TCGCCGTGTACTACTGCCAGCACAGCAGGGACCTGCCCCTGACATTTGGC

  GGAGGCACCAAGGTGGAAATCAAG]

  [Spacer (SEQ ID NO: 362)]

  [PM1 PM07 2001 (SEQ ID NO: 1490)]

  Amino Acid Sequence:

  (SEQ ID NO: 1491)

  [QGQSGQG][ELCGWQSFSGVCTSEGGGSSGGSISSGLLSGRSDNHGGSE

  IVLTQSPATLSLSPGERATLSCRASKGVSTSGYSYLHWYQQKPGQAPRLL

  IYLASYLESGVPARFSGSGSGTDFTLTISSLEPEDFAVYYCQHSRDLPLT

  FGGGTKVEIK]

  PM1 PM07 2001 Amino Acid Sequence:

  (SEQ ID NO: 1490)

  ELCGWQSFSGVCTSEGGGSSGGSISSGLLSGRSDNHGGSEIVLTQSPATL

  SLSPGERATLSCRASKGVSTSGYSYLHWYQQKPGQAPRLLIYLASYLESG

  VPARFSGSGSGTDFTLTISSLEPEDFAVYYCQHSRDLPLTFGGGTKVEIK

  [Spacer (SEQ ID NO: 918)]

  [PM1 PM07 2001 (SEQ ID NO: 1492)]

  Nucleotide Sequence:

  (SEQ ID NO: 1493)

  [CAAGGCCAGTCTGGCCAAGGT][GAGTTGTGCGGTTGGCAGAGTTTTTC

  GGGGGTTTGCACTAGTGAGGGAGGTGGCTCGAGCGGCGGCTCTATCTCTT

  CCGGACTGCTGTCCGGCAGATCCGACAATCACGGCGGATCCGAGATCGTG

  CTGACACAGAGCCCTGCCACCCTGTCTCTGAGCCCTGGCGAAAGAGCCAC

  CCTGAGCTGTAGAGCCTCTAAGGGCGTGTCCACCAGCGGCTACAGCTACC

  TGCACTGGTATCAGCAGAAGCCCGGCCAGGCCCCCAGACTGCTGATCTAC

  CTGGCCTCCTACCTGGAAAGCGGCGTGCCCGCCAGATTTTCTGGCTCTGG

  CAGCGGCACCGACTTCACCCTGACAATCAGCAGCCTGGAACCCGAGGACT

  TCGCCGTGTACTACTGCCAGCACAGCAGGGACCTGCCCCTGACATTTGGC

  GGAGGCACCAAGGTGGAAATCAAG]

  [Spacer (SEQ ID NO: 362)]

  [PM1 PM08 2001 (SEQ ID NO: 1494)]

  Amino Acid Sequence:

  (SEQ ID NO: 1495)

  [QGQSGQG][WTYENCWASCQPHLEGGGSSGGSISSGLLSGRSDNHGGSE

  IVLTQSPATLSLSPGERATLSCRASKGVSTSGYSYLHWYQQKPGQAPRLL

  IYLASYLESGVPARFSGSGSGTDFTLTISSLEPEDFAVYYCQHSRDLPLT

  FGGGTKVEIK]

  PM1 PM08 2001 Amino Acid Sequence:

  (SEQ ID NO: 1494)

  WTYENCWASCQPHLEGGGSSGGSISSGLLSGRSDNHGGSEIVLTQSPATL

  SLSPGERATLSCRASKGVSTSGYSYLHWYQQKPGQAPRLLIYLASYLESG

  VPARFSGSGSGTDFTLTISSLEPEDFAVYYCQHSRDLPLTFGGGTKVEIK

  [Spacer (SEQ ID NO: 918)]

  [PM1 PM08 2001 (SEQ ID NO: 1496)]

  Nucleotide Sequence:

  (SEQ ID NO: 1497)

  [CAAGGCCAGTCTGGCCAAGGT][TGGACTTATGAGAATTGCTGGGCTTC

  GTGCCAGCCTCATTTGGAGGGAGGTGGCTCGAGCGGCGGCTCTATCTCTT

  CCGGACTGCTGTCCGGCAGATCCGACAATCACGGCGGATCCGAGATCGTG

  CTGACACAGAGCCCTGCCACCCTGTCTCTGAGCCCTGGCGAAAGAGCCAC

  CCTGAGCTGTAGAGCCTCTAAGGGCGTGTCCACCAGCGGCTACAGCTACC

  TGCACTGGTATCAGCAGAAGCCCGGCCAGGCCCCCAGACTGCTGATCTAC

  CTGGCCTCCTACCTGGAAAGCGGCGTGCCCGCCAGATTTTCTGGCTCTGG

  CAGCGGCACCGACTTCACCCTGACAATCAGCAGCCTGGAACCCGAGGACT

  TCGCCGTGTACTACTGCCAGCACAGCAGGGACCTGCCCCTGACATTTGGC

  GGAGGCACCAAGGTGGAAATCAAG]

  [Spacer (SEQ ID NO: 913)]

  [PM1 PM09 2001 (SEQ ID NO: 1498)]

  Amino Acid Sequence:

  (SEQ ID NO: 1499)

  [QGQSGQ][KLTEDFSSAAGSSGGSISSGLLSGRSDNHGGSEIVLTQSPA

  TLSLSPGERATLSCRASKGVSTSGYSYLHWYQQKPGQAPRLLIYLASYLE

  SGVPARFSGSGSGTDFTLTISSLEPEDFAVYYCQHSRDLPLTFGGGTKVE

  IK]

  PM1 PM09 2001 Amino Acid Sequence:

  (SEQ ID NO: 1498)

  KLTEDFSSAAGSSGGSISSGLLSGRSDNHGGSEIVLTQSPATLSLSPGER

  ATLSCRASKGVSTSGYSYLHWYQQKPGQAPRLLIYLASYLESGVPARFSG

  SGSGTDFTLTISSLEPEDFAVYYCQHSRDLPLTFGGGTKVEIK

  [Spacer (SEQ ID NO: 1518)]

  [PM1 PM09 2001 (SEQ ID NO: 1500)]

  Nucleotide Sequence:

  (SEQ ID NO: 1501)

  [CAAGGCCAGTCTGGCCAA][AAGCTTACTGAGGATTTTTCTAGCGCAGC

  AGGCTCGAGCGGCGGCTCTATCTCTTCCGGACTGCTGTCCGGCAGATCCG

  ACAATCACGGCGGATCCGAGATCGTGCTGACACAGAGCCCTGCCACCCTG

  TCTCTGAGCCCTGGCGAAAGAGCCACCCTGAGCTGTAGAGCCTCTAAGGG

  CGTGTCCACCAGCGGCTACAGCTACCTGCACTGGTATCAGCAGAAGCCCG

  GCCAGGCCCCCAGACTGCTGATCTACCTGGCCTCCTACCTGGAAAGCGGC

  GTGCCCGCCAGATTTTCTGGCTCTGGCAGCGGCACCGACTTCACCCTGAC

  AATCAGCAGCCTGGAACCCGAGGACTTCGCCGTGTACTACTGCCAGCACA

  GCAGGGACCTGCCCCTGACATTTGGCGGAGGCACCAAGGTGGAAATC

  AAG]

  [Spacer (SEQ ID NO: 362)]

  [PM1 PM10 2001 (SEQ ID NO: 1502)]

  Amino Acid Sequence:

  (SEQ ID NO: 1503)

  [QGQSGQG][VGQSCFSGLVCDRQLGGGSSGGSISSGLLSGRSDNHGGSE

  IVLTQSPATLSLSPGERATLSCRASKGVSTSGYSYLHWYQQKPGQAPRLL

  IYLASYLESGVPARFSGSGSGTDFTLTISSLEPEDFAVYYCQHSRDLPLT

  FGGGTKVEIK]

  PM1 PM10 2001 Amino Acid Sequence:

  (SEQ ID NO: 1502)

  VGQSCFSGLVCDRQLGGGSSGGSISSGLLSGRSDNHGGSEIVLTQSPATL

  SLSPGERATLSCRASKGVSTSGYSYLHWYQQKPGQAPRLLIYLASYLESG

  VPARFSGSGSGTDFTLTISSLEPEDFAVYYCQHSRDLPLTFGGGTKVEIK

  [Spacer (SEQ ID NO: 918)]

  [PM1 PM10 2001 (SEQ ID NO: 1504)]

  Nucleotide Sequence:

  (SEQ ID NO: 1505)

  [CAAGGCCAGTCTGGCCAAGGT][GTGGGGCAGAGTTGCTTTTCTGGGCT

  GGTTTGCGATAGGCAGCTGGGAGGTGGCTCGAGCGGCGGCTCTATCTCTT

  CCGGACTGCTGTCCGGCAGATCCGACAATCACGGCGGATCCGAGATCGTG

  CTGACACAGAGCCCTGCCACCCTGTCTCTGAGCCCTGGCGAAAGAGCCAC

  CCTGAGCTGTAGAGCCTCTAAGGGCGTGTCCACCAGCGGCTACAGCTACC

  TGCACTGGTATCAGCAGAAGCCCGGCCAGGCCCCCAGACTGCTGATCTAC

  CTGGCCTCCTACCTGGAAAGCGGCGTGCCCGCCAGATTTTCTGGCTCTGG

  CAGCGGCACCGACTTCACCCTGACAATCAGCAGCCTGGAACCCGAGGACT

  TCGCCGTGTACTACTGCCAGCACAGCAGGGACCTGCCCCTGACATTTGGC

  GGAGGCACCAAGGTGGAAATCAAG]

  [Spacer (SEQ ID NO: 913)]

  [PM1 PM11 2001 (SEQ ID NO: 1506)]

  Amino Acid Sequence:

  (SEQ ID NO: 1507)

  [QGQSGQ][ISHYCFSGKSCRDGSSGGSISSGLLSGRSDNHGGSEIVLTQ

  SPATLSLSPGERATLSCRASKGVSTSGYSYLHWYQQKPGQAPRLLIYLAS

  YLESGVPARFSGSGSGTDFTLTISSLEPEDFAVYYCQHSRDLPLTFGGGT

  KVEIK]

  PM1 PM11 2001 Amino Acid Sequence:

  (SEQ ID NO: 1506)

  ISHYCFSGKSCRDGSSGGSISSGLLSGRSDNHGGSEIVLTQSPATLSLSP

  GERATLSCRASKGVSTSGYSYLHWYQQKPGQAPRLLIYLASYLESGVPAR

  FSGSGSGTDFTLTISSLEPEDFAVYYCQHSRDLPLTFGGGTKVEIK

  [Spacer (SEQ ID NO: 1518)]

  [PM1 PM11 2001 (SEQ ID NO: 1508)]

  Nucleotide Sequence:

  (SEQ ID NO: 1509)

  [CAAGGCCAGTCTGGCCAA][ATCTCTCACTATTGTTTCAGTGGCAAATC

  CTGCAGGGACGGCTCGAGCGGCGGCTCTATCTCTTCCGGACTGCTGTCCG

  GCAGATCCGACAATCACGGCGGATCCGAGATCGTGCTGACACAGAGCCCT

  GCCACCCTGTCTCTGAGCCCTGGCGAAAGAGCCACCCTGAGCTGTAGAGC

  CTCTAAGGGCGTGTCCACCAGCGGCTACAGCTACCTGCACTGGTATCAGC

  AGAAGCCCGGCCAGGCCCCCAGACTGCTGATCTACCTGGCCTCCTACCTG

  GAAAGCGGCGTGCCCGCCAGATTTTCTGGCTCTGGCAGCGGCACCGACTT

  CACCCTGACAATCAGCAGCCTGGAACCCGAGGACTTCGCCGTGTACTACT

  GCCAGCACAGCAGGGACCTGCCCCTGACATTTGGCGGAGGCACCAAGGTG

  GAAATCAAG]

  [Spacer (SEQ ID NO: 362)]

  [PM1 PM12 2001 (SEQ ID NO: 1510)]

  Amino Acid Sequence:

  (SEQ ID NO: 1511)

  [QGQSGQG][HCIPDFTSAAGDCMRGGGSSGGSISSGLLSGRSDNHGGSE

  IVLTQSPATLSLSPGERATLSCRASKGVSTSGYSYLHWYQQKPGQAPRLL

  IYLASYLESGVPARFSGSGSGTDFTLTISSLEPEDFAVYYCQHSRDLPLT

  FGGGTKVEIK]

  PM1 PM12 2001 Amino Acid Sequence:

  (SEQ ID NO: 1510)

  HCIPDFTSAAGDCMRGGGSSGGSISSGLLSGRSDNHGGSEIVLTQSPATL

  SLSPGERATLSCRASKGVSTSGYSYLHWYQQKPGQAPRLLIYLASYLESG

  VPARFSGSGSGTDFTLTISSLEPEDFAVYYCQHSRDLPLTFGGGTKVEIK

  [Spacer (SEQ ID NO: 918)]

  [PM1 PM12 2001 (SEQ ID NO: 1512)]

  Nucleotide Sequence:

  (SEQ ID NO: 1513)

  [CAAGGCCAGTCTGGCCAAGGT][CATTGCATTCCTGATTTTACTTCTGC

  TGCTGGTGATTGCATGAGGGGAGGTGGCTCGAGCGGCGGCTCTATCTCTT

  CCGGACTGCTGTCCGGCAGATCCGACAATCACGGCGGATCCGAGATCGTG

  CTGACACAGAGCCCTGCCACCCTGTCTCTGAGCCCTGGCGAAAGAGCCAC

  CCTGAGCTGTAGAGCCTCTAAGGGCGTGTCCACCAGCGGCTACAGCTACC

  TGCACTGGTATCAGCAGAAGCCCGGCCAGGCCCCCAGACTGCTGATCTAC

  CTGGCCTCCTACCTGGAAAGCGGCGTGCCCGCCAGATTTTCTGGCTCTGG

  CAGCGGCACCGACTTCACCCTGACAATCAGCAGCCTGGAACCCGAGGACT

  TCGCCGTGTACTACTGCCAGCACAGCAGGGACCTGCCCCTGACATTTGGC

  GGAGGCACCAAGGTGGAAATCAAG]

  PM1 HC Variable

  (SEQ ID NO: 1514)

  QVQLVQSGVEVKKPGASVKVSCKASGYTFTNYYMYWVRQAPGQGLEWMGG

  INPSNGGTNFNEKFKNRVTLTTDSSTTTAYMELKSLQFDDTAVYYCARRD

  YRFDMGFDYWGQGTTVTVSS

  PM1 HC Variable

  (SEQ ID NO: 1515)

  CAGGTGCAGCTGGTGCAGTCTGGCGTGGAAGTGAAGAAACCAGGCGCCAG

  CGTGAAGGTGTCCTGCAAGGCCAGCGGCTACACCTTTACCAACTACTACA

  TGTACTGGGTGCGCCAGGCCCCAGGCCAGGGACTGGAATGGATGGGCGGC

  ATCAACCCCAGCAACGGCGGCACCAACTTCAACGAGAAGTTCAAGAACAG

  AGTGACCCTGACCACCGACAGCAGCACCACCACCGCCTACATGGAACTGA

  AGTCCCTGCAGTTCGACGACACCGCCGTGTACTACTGCGCCAGACGGGAC

  TACAGATTCGACATGGGCTTCGACTACTGGGGCCAGGGCACAACCGTGAC

  CGTGTCTAGT

Example 24: Characterization of Activatable Anti-PD1 PM1 Antibodies
• This example describes activatable anti-PD1 PM1 antibodies with reduced binding to hPD1.
• Masking efficiencies were evaluated by standard plate ELISA. Briefly, human PD1-Fc (R and D systems, Minneapolis, Minn.) was adsorbed to the wells of a 96-well ELISA plate. Purified PM1 and activatable PM1 antibodies were applied to the plate in serial dilution and allowed to bind. Bound antibody and activatable antibodies were detected with anti-hu Fab-HRP conjugate (Sigma, St Louis, Mo.) and visualized with the chromogenic substrate TMB (Thermo Scientific, Rockford, Ill.). Plots were generated in Prizm (Sigma Plot). All activatable PM1 antibodies showed decreased binding compared with the parental PM1, as shown in FIGS. 27A, 27B, and 27C.
Example 25: Characterization of Anti-PD1 Activatable Antibodies of the Disclosure
• The binding properties of several masking moieties of the disclosure identified for A1.5 (PD), NV1 (NV) and PM1 (PM) antibodies were evaluated. Eight peptide clones from each mask discovery effort were grown overnight at 37° C., 850 rpm in 2 mL deep well plates in LB+Chloramphenicol+0.2% glucose, diluted 1:20 in LB+Chloramphenicol and grown 105 minutes at 37° C., 850 rpm. Peptide expression was induced by the addition of 0.04% arabinose for 35 minutes, and clones were stained with 1 nM A1.5-DyLight 650, 1 nM PM1-Dylight 650 and 1 nM NV1-Dylight 650 in cold PBS+0.5% BSA. Clones were pelleted, the staining solution was removed, and cells were resuspended in PBS+1% formaldehyde. Fluorescence was measured on a MACSQuant Analyzer 10 flow cytometer manufactured by Miltenyi Biotec, Inc. (San Diego, Calif.). As shown in FIG. 28, masking moieties bound to the anti-PD1 antibody used in the library screening from which they were identified.
Example 26: Evaluation of Masking Moiety Binding by Effector Negative Activatable Antibodies
• This example describes additional activatable anti-PD-1 J43 antibodies that exhibit reduced binding to mouse PD-1.
• Examples of additional activatable antibodies of the disclosure comprising an IgG2a effector negative (EN) anti-PD1 antibody J43 (J43 m2a EN) and a variety of mask and substrate combinations were produced using techniques as described herein. The amino acid and nucleic acid sequences of the constant region of the IgG2a EN antibody are provided below. A plasmid encoding this effector negative Fc region, pFUSE-mIgG2Ae1-Fc, is available from InvivoGen, San Diego, Calif. The Fc region of mIgG2a was engineered by mutating the following amino acids to reduce binding to FcR and C1q: L235E and E318A/K320A/K322A.

• +LT,1 >mIgG2a EN

  (SEQ ID NO: 1516)

  AKTTAPSVYPLAPVCGDTTGSSVTLGCLVKGYFPEPVTLTWNSGSLSSGV

  HTFPAVLQSDLYTLSSSVTVTSSTWPSQSITCNVAHPASSTKVDKKIEPR

  GPTIKPCPPCKCPAPNLEGGPSVFIFPPKIKDVLMISLSPIVTCVVVDVS

  EDDPDVQISWFVNNVEVHTAQTQTHREDYNSTLRVVSALPIQHQDWMSGK

  AFACAVNNKDLPAPIERTISKPKGSVRAPQVYVLPPPEEEMTKKQVTLTC

  MVTDFMPEDIYVEWTNNGKTELNYKNTEPVLDSDGSYFMYSKLRVEKKNW

  VERNSYSCSVVHEGLHNHHTTKSFSRTPGK

  >mIgG2a EN

  (SEQ ID NO: 1517)

  GCCAAGACAACAGCCCCCAGCGTGTACCCTCTGGCCCCTGTGTGTGGCGA

  TACCACAGGCAGCTCTGTGACCCTGGGCTGCCTCGTGAAGGGCTACTTCC

  CTGAGCCAGTGACCCTGACCTGGAACAGCGGCTCTCTGTCTAGCGGCGTG

  CACACCTTTCCAGCCGTGCTGCAGAGCGACCTGTACACCCTGAGCAGCAG

  CGTGACCGTGACCAGCAGCACATGGCCCAGCCAGAGCATCACCTGTAACG

  TGGCCCACCCTGCCAGCTCCACCAAGGTGGACAAGAAGATCGAGCCCAGA

  GGCCCCACCATCAAGCCTTGCCCCCCTTGCAAATGCCCTGCCCCCAATCT

  GGAAGGCGGCCCTAGCGTGTTCATCTTCCCACCCAAGATCAAGGACGTGC

  TGATGATCAGCCTGAGCCCCATCGTGACCTGCGTGGTGGTGGACGTGTCC

  GAGGACGACCCCGATGTGCAGATCAGTTGGTTCGTGAACAACGTGGAAGT

  GCACACCGCCCAGACCCAGACACACAGAGAGGACTACAACAGCACCCTGA

  GAGTGGTGTCCGCCCTGCCCATCCAGCACCAGGATTGGATGAGCGGCAAG

  GCCTTCGCCTGCGCTGTGAACAACAAGGACCTGCCAGCCCCCATCGAGCG

  GACCATCTCTAAGCCTAAGGGCAGCGTGCGGGCTCCCCAGGTGTACGTGC

  TGCCTCCTCCAGAGGAAGAGATGACCAAGAAACAAGTGACACTGACATGC

  ATGGTCACCGACTTCATGCCCGAGGACATCTACGTGGAATGGACCAACAA

  CGGCAAGACCGAGCTGAACTACAAGAACACCGAGCCCGTGCTGGACAGCG

  ACGGCAGCTACTTCATGTACAGCAAGCTGCGGGTGGAAAAGAAAAACTGG

  GTGGAACGGAACAGCTACAGCTGCAGCGTGGTGCACGAGGGCCTGCACAA

  TCACCACACCACCAAGAGCTTCAGCCGGACCCCTGGAAAA

• Masking efficiencies of several of these activatable antibodies were determined as described herein. The results are shown in FIG. 29A and FIG. 29B.
J43m2a EN Activatable Antibody LCs:

• [Spacer (SEQ ID NO: 362)]

  [J43m2a EN MP8-2 2001 (SEQ ID NO: 1808)] Amino Acid Sequence:

  (SEQ ID NO: 1809)

  [QGQSGQG][ACRICQDHPATKWNSGGGSSGGSISSGLLSGRSDNHGGGS

  YELTQPPSASVNVGETVKITCSGDQLPKYFADWFHQRSDQTILQVIYDDN

  KRPSGIPERISGSSSGTTATLTIRDVRAEDEGDYYCFSGYVDSDSKLYVF

  GSGTQLTVLGGPKSSPKVTVFPPSPEELRTNKATLVCLVNDFYPGSATVT

  WKANGATINDGVKTTKPSKQGQNYMTSSYLSLTADQWKSHNRVSCQVTHE

  GETVEKSLSPAECL]

  J43m2a EN MP8-2 2001 Amino Acid Sequence:

  (SEQ ID NO: 1808)

  ACRICQDHPATKWNSGGGSSGGSISSGLLSGRSDNHGGGSYELTQPPSAS

  VNVGETVKITCSGDQLPKYFADWFHQRSDQTILQVIYDDNKRPSGIPERI

  SGSSSGTTATLTIRDVRAEDEGDYYCFSGYVDSDSKLYVFGSGTQLTVLG

  GPKSSPKVTVFPPSPEELRTNKATLVCLVNDFYPGSATVTWKANGATIND

  GVKTTKPSKQGQNYMTSSYLSLTADQWKSHNRVSCQVTHEGETVEKSLSP

  AECL

  [Spacer (SEQ ID NO: 362)]

  [J43m2a EN MP8-2 2011 (SEQ ID NO: 1810)]

  Amino Acid Sequence:

  (SEQ ID NO: 1811)

  [QGQSGQG][ACRICQDHPATKWNSGGGSSGGSISSGLLSGRSDNPGGGS

  YELTQPPSASVNVGETVKITCSGDQLPKYFADWFHQRSDQTILQVIYDDN

  KRPSGIPERISGSSSGTTATLTIRDVRAEDEGDYYCFSGYVDSDSKLYVF

  GSGTQLTVLGGPKSSPKVTVFPPSPEELRTNKATLVCLVNDFYPGSATVT

  WKANGATINDGVKTTKPSKQGQNYMTSSYLSLTADQWKSHNRVSCQVTHE

  GETVEKSLSPAECL]

  J43m2a EN MP8-2 2011 Amino Acid Sequence:

  (SEQ ID NO: 1810)

  ACRICQDHPATKWNSGGGSSGGSISSGLLSGRSDNPGGGSYELTQPPSAS

  VNVGETVKITCSGDQLPKYFADWFHQRSDQTILQVIYDDNKRPSGIPERI

  SGSSSGTTATLTIRDVRAEDEGDYYCFSGYVDSDSKLYVFGSGTQLTVLG

  GPKSSPKVTVFPPSPEELRTNKATLVCLVNDFYPGSATVTWKANGATIND

  GVKTTKPSKQGQNYMTSSYLSLTADQWKSHNRVSCQVTHEGETVEKSLSP

  AECL

  [Spacer (SEQ ID NO: 362)]

  [J43m2a EN MP8-2 2012 (SEQ ID NO: 1812)]

  Amino Acid Sequence:

  (SEQ ID NO: 1813)

  [QGQSGQG][ACRICQDHPATKWNSGGGSSGGSISSGLLSGRSANPGGGS

  YELTQPPSASVNVGETVKITCSGDQLPKYFADWFHQRSDQTILQVIYDDN

  KRPSGIPERISGSSSGTTATLTIRDVRAEDEGDYYCFSGYVDSDSKLYVF

  GSGTQLTVLGGPKSSPKVTVFPPSPEELRTNKATLVCLVNDFYPGSATVT

  WKANGATINDGVKTTKPSKQGQNYMTSSYLSLTADQWKSHNRVSCQVTHE

  GETVEKSLSPAECL]

  J43m2a EN MP8-2 2012 Amino Acid Sequence:

  (SEQ ID NO: 1812)

  ACRICQDHPATKWNSGGGSSGGSISSGLLSGRSANPGGGSYELTQPPSAS

  VNVGETVKITCSGDQLPKYFADWFHQRSDQTILQVIYDDNKRPSGIPERI

  SGSSSGTTATLTIRDVRAEDEGDYYCFSGYVDSDSKLYVFGSGTQLTVLG

  GPKSSPKVTVFPPSPEELRTNKATLVCLVNDFYPGSATVTWKANGATIND

  GVKTTKPSKQGQNYMTSSYLSLTADQWKSHNRVSCQVTHEGETVEKSLSP

  AECL

  [Spacer (SEQ ID NO: 362)]

  [J43m2a EN MP8-2 2002 (SEQ ID NO: 1814)]

  Amino Acid Sequence:

  (SEQ ID NO: 1815)

  [QGQSGQG][ACRICQDHPATKWNSGGGSSGGSISSGLLSGRSGNHGGGS

  YELTQPPSASVNVGETVKITCSGDQLPKYFADWFHQRSDQTILQVIYDDN

  KRPSGIPERISGSSSGTTATLTIRDVRAEDEGDYYCFSGYVDSDSKLYVF

  GSGTQLTVLGGPKSSPKVTVFPPSPEELRTNKATLVCLVNDFYPGSATVT

  WKANGATINDGVKTTKPSKQGQNYMTSSYLSLTADQWKSHNRVSCQVTHE

  GETVEKSLSPAECL]

  J43m2a EN MP8-2 2002 Amino Acid Sequence:

  (SEQ ID NO: 1814)

  ACRICQDHPATKWNSGGGSSGGSISSGLLSGRSGNHGGGSYELTQPPSAS

  VNVGETVKITCSGDQLPKYFADWFHQRSDQTILQVIYDDNKRPSGIPERI

  SGSSSGTTATLTIRDVRAEDEGDYYCFSGYVDSDSKLYVFGSGTQLTVLG

  GPKSSPKVTVFPPSPEELRTNKATLVCLVNDFYPGSATVTWKANGATIND

  GVKTTKPSKQGQNYMTSSYLSLTADQWKSHNRVSCQVTHEGETVEKSLSP

  AECL

  [Spacer (SEQ ID NO: 362)]

  [J43m2a EN MP8-2 2003 (SEQ ID NO: 1816)]

  Amino Acid Sequence:

  (SEQ ID NO: 1817)

  [QGQSGQG][ACRICQDHPATKWNSGGGSSGGSISSGLLSGRSANPRGGG

  GSYELTQPPSASVNVGETVKITCSGDQLPKYFADWFHQRSDQTILQVIYD

  DNKRPSGIPERISGSSSGTTATLTIRDVRAEDEGDYYCFSGYVDSDSKLY

  VFGSGTQLTVLGGPKSSPKVTVFPPSPEELRTNKATLVCLVNDFYPGSAT

  VTWKANGATINDGVKTTKPSKQGQNYMTSSYLSLTADQWKSHNRVSCQVT

  HEGETVEKSLSPAECL]

  J43m2a EN MP8-2 2003 Amino Acid Sequence:

  (SEQ ID NO: 1816)

  ACRICQDHPATKWNSGGGSSGGSISSGLLSGRSANPRGGGGSYELTQPPS

  ASVNVGETVKITCSGDQLPKYFADWFHQRSDQTILQVIYDDNKRPSGIPE

  RISGSSSGTTATLTIRDVRAEDEGDYYCFSGYVDSDSKLYVFGSGTQLTV

  LGGPKSSPKVTVFPPSPEELRTNKATLVCLVNDFYPGSATVTWKANGATI

  NDGVKTTKPSKQGQNYMTSSYLSLTADQWKSHNRVSCQVTHEGETVEKSL

  SPAECL

  [Spacer (SEQ ID NO: 362)]

  [J43m2a EN MP8-2 2006 (SEQ ID NO: 1818)]

  Amino Acid Sequence:

  (SEQ ID NO: 1819)

  [QGQSGQG][ACRICQDHPATKWNSGGGSSGGSISSGLLSGRSDDHGGGS

  YELTQPPSASVNVGETVKITCSGDQLPKYFADWFHQRSDQTILQVIYDDN

  KRPSGIPERISGSSSGTTATLTIRDVRAEDEGDYYCFSGYVDSDSKLYVF

  GSGTQLTVLGGPKSSPKVTVFPPSPEELRTNKATLVCLVNDFYPGSATVT

  WKANGATINDGVKTTKPSKQGQNYMTSSYLSLTADQWKSHNRVSCQVTHE

  GETVEKSLSPAECL]

  J43m2a EN MP8-2 2006 Amino Acid Sequence:

  (SEQ ID NO: 1818)

  ACRICQDHPATKWNSGGGSSGGSISSGLLSGRSDDHGGGSYELTQPPSAS

  VNVGETVKITCSGDQLPKYFADWFHQRSDQTILQVIYDDNKRPSGIPERI

  SGSSSGTTATLTIRDVRAEDEGDYYCFSGYVDSDSKLYVFGSGTQLTVLG

  GPKSSPKVTVFPPSPEELRTNKATLVCLVNDFYPGSATVTWKANGATIND

  GVKTTKPSKQGQNYMTSSYLSLTADQWKSHNRVSCQVTHEGETVEKSLSP

  AECL

  [Spacer (SEQ ID NO: 362)]

  [J43m2a EN MP8-2 2007 (SEQ ID NO: 1820)]

  Amino Acid Sequence:

  (SEQ ID NO: 1821)

  [QGQSGQG][ACRICQDHPATKWNSGGGSSGGSISSGLLSGRSDIHGGGS

  YELTQPPSASVNVGETVKITCSGDQLPKYFADWFHQRSDQTILQVIYDDN

  KRPSGIPERISGSSSGTTATLTIRDVRAEDEGDYYCFSGYVDSDSKLYVF

  GSGTQLTVLGGPKSSPKVTVFPPSPEELRTNKATLVCLVNDFYPGSATVT

  WKANGATINDGVKTTKPSKQGQNYMTSSYLSLTADQWKSHNRVSCQVTHE

  GETVEKSLSPAECL]

  J43m2a EN MP8-2 2007 Amino Acid Sequence:

  (SEQ ID NO: 1820)

  ACRICQDHPATKWNSGGGSSGGSISSGLLSGRSDIHGGGSYELTQPPSAS

  VNVGETVKITCSGDQLPKYFADWFHQRSDQTILQVIYDDNKRPSGIPERI

  SGSSSGTTATLTIRDVRAEDEGDYYCFSGYVDSDSKLYVFGSGTQLTVLG

  GPKSSPKVTVFPPSPEELRTNKATLVCLVNDFYPGSATVTWKANGATIND

  GVKTTKPSKQGQNYMTSSYLSLTADQWKSHNRVSCQVTHEGETVEKSLSP

  AECL

  [Spacer (SEQ ID NO: 362)]

  [J43m2a EN MP8-2 2008 (SEQ ID NO: 1822)]

  Amino Acid Sequence:

  (SEQ ID NO: 1823)

  [QGQSGQG][ACRICQDHPATKWNSGGGSSGGSISSGLLSGRSDQHGGGS

  YELTQPPSASVNVGETVKITCSGDQLPKYFADWFHQRSDQTILQVIYDDN

  KRPSGIPERISGSSSGTTATLTIRDVRAEDEGDYYCFSGYVDSDSKLYVF

  GSGTQLTVLGGPKSSPKVTVFPPSPEELRTNKATLVCLVNDFYPGSATVT

  WKANGATINDGVKTTKPSKQGQNYMTSSYLSLTADQWKSHNRVSCQVTHE

  GETVEKSLSPAECL]

  J43m2a EN MP8-2 2008 Amino Acid Sequence:

  (SEQ ID NO: 1822)

  ACRICQDHPATKWNSGGGSSGGSISSGLLSGRSDQHGGGSYELTQPPSAS

  VNVGETVKITCSGDQLPKYFADWFHQRSDQTILQVIYDDNKRPSGIPERI

  SGSSSGTTATLTIRDVRAEDEGDYYCFSGYVDSDSKLYVFGSGTQLTVLG

  GPKSSPKVTVFPPSPEELRTNKATLVCLVNDFYPGSATVTWKANGATIND

  GVKTTKPSKQGQNYMTSSYLSLTADQWKSHNRVSCQVTHEGETVEKSLSP

  AECL

  [Spacer (SEQ ID NO: 362)]

  [J43m2a EN MP8-2 2009 (SEQ ID NO: 1824)]

  Amino Acid Sequence:

  (SEQ ID NO: 1825)

  [QGQSGQG][ACRICQDHPATKWNSGGGSSGGSISSGLLSGRSDTHGGGS

  YELTQPPSASVNVGETVKITCSGDQLPKYFADWFHQRSDQTILQVIYDDN

  KRPSGIPERISGSSSGTTATLTIRDVRAEDEGDYYCFSGYVDSDSKLYVF

  GSGTQLTVLGGPKSSPKVTVFPPSPEELRTNKATLVCLVNDFYPGSATVT

  WKANGATINDGVKTTKPSKQGQNYMTSSYLSLTADQWKSHNRVSCQVTHE

  GETVEKSLSPAECL]

  J43m2a EN MP8-2 2009 Amino Acid Sequence:

  (SEQ ID NO: 1824)

  ACRICQDHPATKWNSGGGSSGGSISSGLLSGRSDTHGGGSYELTQPPSAS

  VNVGETVKITCSGDQLPKYFADWFHQRSDQTILQVIYDDNKRPSGIPERI

  SGSSSGTTATLTIRDVRAEDEGDYYCFSGYVDSDSKLYVFGSGTQLTVLG

  GPKSSPKVTVFPPSPEELRTNKATLVCLVNDFYPGSATVTWKANGATIND

  GVKTTKPSKQGQNYMTSSYLSLTADQWKSHNRVSCQVTHEGETVEKSLSP

  AECL

  [Spacer (SEQ ID NO: 362)]

  [J43m2a EN MP8-2 2010 (SEQ ID NO: 1826)]

  Amino Acid Sequence:

  (SEQ ID NO: 1827)

  [QGQSGQG][ACRICQDHPATKWNSGGGSSGGSISSGLLSGRSDYHGGGS

  YELTQPPSASVNVGETVKITCSGDQLPKYFADWFHQRSDQTILQVIYDDN

  KRPSGIPERISGSSSGTTATLTIRDVRAEDEGDYYCFSGYVDSDSKLYVF

  GSGTQLTVLGGPKSSPKVTVFPPSPEELRTNKATLVCLVNDFYPGSATVT

  WKANGATINDGVKTTKPSKQGQNYMTSSYLSLTADQWKSHNRVSCQVTHE

  GETVEKSLSPAECL]

  J43m2a EN MP8-2 2010 Amino Acid Sequence:

  (SEQ ID NO: 1826)

  ACRICQDHPATKWNSGGGSSGGSISSGLLSGRSDYHGGGSYELTQPPSAS

  VNVGETVKITCSGDQLPKYFADWFHQRSDQTILQVIYDDNKRPSGIPERI

  SGSSSGTTATLTIRDVRAEDEGDYYCFSGYVDSDSKLYVFGSGTQLTVLG

  GPKSSPKVTVFPPSPEELRTNKATLVCLVNDFYPGSATVTWKANGATIND

  GVKTTKPSKQGQNYMTSSYLSLTADQWKSHNRVSCQVTHEGETVEKSLSP

  AECL

  [Spacer (SEQ ID NO: 362)]

  [J43m2a EN MP8-2 2013 (SEQ ID NO: 1828)]

  Amino Acid Sequence:

  (SEQ ID NO: 1829)

  [QGQSGQG][ACRICQDHPATKWNSGGGSSGGSISSGLLSGRSANIGGGS

  YELTQPPSASVNVGETVKITCSGDQLPKYFADWFHQRSDQTILQVIYDDN

  KRPSGIPERISGSSSGTTATLTIRDVRAEDEGDYYCFSGYVDSDSKLYVF

  GSGTQLTVLGGPKSSPKVTVFPPSPEELRTNKATLVCLVNDFYPGSATVT

  WKANGATINDGVKTTKPSKQGQNYMTSSYLSLTADQWKSHNRVSCQVTHE

  GETVEKSLSPAECL]

  J43m2a EN MP8-2 2013 Amino Acid Sequence:

  (SEQ ID NO: 1828)

  ACRICQDHPATKWNSGGGSSGGSISSGLLSGRSANIGGGSYELTQPPSAS

  VNVGETVKITCSGDQLPKYFADWFHQRSDQTILQVIYDDNKRPSGIPERI

  SGSSSGTTATLTIRDVRAEDEGDYYCFSGYVDSDSKLYVFGSGTQLTVLG

  GPKSSPKVTVFPPSPEELRTNKATLVCLVNDFYPGSATVTWKANGATIND

  GVKTTKPSKQGQNYMTSSYLSLTADQWKSHNRVSCQVTHEGETVEKSLSP

  AECL

  [Spacer (SEQ ID NO: 362)]

  [J43m2a EN MP8-2 2014 (SEQ ID NO: 1830)]

  Amino Acid Sequence:

  (SEQ ID NO: 1831)

  [QGQSGQG][ACRICQDHPATKWNSGGGSSGGSISSGLLSGRSDNIGGGS

  YELTQPPSASVNVGETVKITCSGDQLPKYFADWFHQRSDQTILQVIYDDN

  KRPSGIPERISGSSSGTTATLTIRDVRAEDEGDYYCFSGYVDSDSKLYVF

  GSGTQLTVLGGPKSSPKVTVFPPSPEELRTNKATLVCLVNDFYPGSATVT

  WKANGATINDGVKTTKPSKQGQNYMTSSYLSLTADQWKSHNRVSCQVTHE

  GETVEKSLSPAECL]

  J43m2a EN MP8-2 2014 Amino Acid Sequence:

  (SEQ ID NO: 1830)

  ACRICQDHPATKWNSGGGSSGGSISSGLLSGRSDNIGGGSYELTQPPSAS

  VNVGETVKITCSGDQLPKYFADWFHQRSDQTILQVIYDDNKRPSGIPERI

  SGSSSGTTATLTIRDVRAEDEGDYYCFSGYVDSDSKLYVFGSGTQLTVLG

  GPKSSPKVTVFPPSPEELRTNKATLVCLVNDFYPGSATVTWKANGATIND

  GVKTTKPSKQGQNYMTSSYLSLTADQWKSHNRVSCQVTHEGETVEKSLSP

  AECL

Example 27: Activatable Anti-Mouse PD1 J43 m2a EN Antibodies Reduce Incidence of Diabetes in NOD Mice
• In this Example, anti-PD1 J43 m2a EN (effector negative) activatable antibodies were analyzed for the ability to protect from PD1 m2a EN-mediated induction of diabetes in NOD mice.
• The NOD mice, substrain NOD/ShiLtJ, were obtained from Jackson Laboratory at 8 weeks and acclimated on site for 2 weeks. At 10 weeks, mice were checked for diabetes prior to enrollment, grouped, and dosed as set forth in Table 21.

• 					Dose
  				Dose	volume
  Group	Count	Gender	Treatment	(mg/kg)	(mL/kg)	Schedule	Route

  1	7	F	mIgG2a (C1.18.4)	10	10	q7dx1	IP
  2	7	F	Anti-PD-1 J43 m2a EN	10	10	q7dx1	IP
  3	7	F	Anti-PD-1 J43 m2a EN	3	10	q7dx1	IP
  4	7	F	Anti-PD-1 J43 m2a EN	1	10	q7dx1	IP
  5	7	F	J43 MP7-1 2001 m2a EN	10	10	q7dx1	IP
  6	7	F	J43 MP7-1 2001 m2a EN	3	10	q7dx1	IP
  7	7	F	J43 MP8-2 2001 m2a EN	10	10	q7dx1	IP
  8	7	F	J43 MP8-2 2001 m2a EN	3	10	q7dx1	IP

• FIG. 30 which plots % non-diabetic versus number of days post dose, shows that anti-PD-1 J43 antibody induced diabetes in NOD mice with increased frequency as dosage increased. At day eleven post dose, the percentage of non-diabetic mice for the antibody-treated groups was 29%, 43% and 71% for the 10 mg/kg, 3 mg/kg and 1 mg/kg dose groups, respectively. Activatable antibodies J43 MP7-1 2001 m2a EN and J43 MP8-2 2001 m2a EN required increased doses to induce diabetes at frequencies comparable to the parental antibody. At day eleven post dose with J43 MP7-1 2001 m2a EN, 71% of the 10 mg/kg group remained non-diabetic and 86% of the 3 mg/kg were non-diabetic. At day fourteen post dose with J43 MP8-2 2001 m2a EN, 86% of the 10 mg/kg group and 100% of the 3 mg/kg group remained non-diabetic.
Example 28. Activatable Anti-Mouse PD1 J43 m2a EN Antibodies Show Efficacy in the MC38 Syngeneic Tumor Model
• This Example demonstrates that activatable antibodies of the embodiments are able to reduce the growth of MC38 syngeneic tumors.
• In this Example, anti-PD1 activatable antibodies J43 MP7-1 2001 m2a EN and J43 MP8-2 2001 m2a EN were analyzed for the ability to reduce the growth of MC38 syngeneic tumors.
• The mouse colon carcinoma cell line MC38 was obtained from ATCC. MC38 were grown in RPMI-1640 supplemented with 10% fetal bovine serum at 37° C. in an atmosphere of 5% CO₂ in air. Cells were harvested during the logarithmic growth period, resuspended in PBS with proper cell concentration, and kept on ice for tumor induction.
• Each mouse was inoculated subcutaneously at the right flank with 1.5×10⁶ of MC38 cells in PBS for tumor development. The treatments were started when the mean tumor size reached approximately 80 mm³ (60-120 mm³). Tumor sizes were measured twice weekly in two dimensions using a caliper, and the volume was expressed in mm³ using the formula: V=0.5 a×b² where a and b are the long and short diameters of the tumor, respectively.
• The mice were grouped and dosed as set forth in Table 22.

• TABLE 22
  			Dose	Dose volume
  Group	Count	Treatment	(mg/kg)	(mL/kg)	Schedule	Route
  1	10	mIgG1 MOPC-21 + mIgG12b	10 + 10	10	b.i.w. for	IP
  		MPC-11			3 weeks
  2	10	Anti-CTLA4 9D9 mIgG2b	10	10	b.i.w. for	IP
  					3 weeks
  3	10	Anti-PD-1 (J43 m2a EN)	10	10	b.i.w. for	IP
  					3 weeks
  4	10	J43 MP8-2 2001 m2a EN	10	10	b.i.w. for	IP
  					3 weeks
  5	10	J43 MP7-1 2001 m2a EN	10	10	b.i.w. for	IP
  					3 weeks
  6	10	Anti-PD-1 (J43 m2a EN) +	10 + 10	10	b.i.w. for	IP
  		Anti-CTLA4 9D9 mIgG2b			3 weeks
  7	10	J43 MP8-2 2001 m2a EN +	10 + 10	10	b.i.w. for	IP
  		Anti-CTLA4 9D9 mIgG2b			3 weeks
  8	10	J43 MP7-1 2001 m2a EN +	10 + 10	10	b.i.w. for	IP
  		Anti-CTLA4 9D9 mIgG2b			3 weeks

• FIGS. 31A and 31B, which plots tumor volume versus number of days post initial dose, demonstrates that anti-PD1 activatable antibodies MP7-1 2001 m2a EN and MP8-2 2001 m2a EN inhibit the growth of MC38 syngeneic tumors similar to positive control anti-PD1 antibody J43 m2a EN both as single agents and in combination with anti-CTLA4 antibody 9D9 mIgG2b (BioXCell, West Lebanon, N.H.).
Example 29. Evaluation of Anti-Human PD1 Antibodies and Activatable Anti-Human PD1 Antibodies in Antigen Recall Assay
• This Example demonstrates that anti-PD1 antibodies and activated activatable anti-PD1 antibodies of the embodiments (i.e., activatable antibodies in which the CM has been cleaved by a protease) are able to block PD-L1/PD-L2 binding to PD1 and to activate T cells in an antigen recall assay.
• As shown in FIGS. 32A-32E, the anti-human PD1 antibody referred to herein as A1.5 Ab (i.e., VH of SEQ ID NO: 21 and VL of SEQ ID NO: 47) blocks PD-L1/PD-L2 binding to PD1 and potently activates T cells in an antigen recall assay. The binding of the anti-human PD-1 A1.5 Ab to immobilized human PD1 as detected by standard plate ELISA is shown in FIG. 32A, and the binding of A1.5 Ab to cynomolgus PD1 (also referred to herein as cyno-PD1, Sino Biological Cat. #90311-CO2H) as detected by ELISA is shown in FIG. 32B. The inhibition of biotinylated human PD-L1 (also referred to herein as biotin-PD-L1) to immobilized PD1 by A1.5 Ab as determined by ELISA is shown in FIG. 32C, and the inhibition of biotinylated human PD-L2 (also referred to herein as biotin-PD-L2) to immobilized PD1 as determined by ELISA is shown in FIG. 32D.
• As shown in FIG. 32E, the A1.5 Ab enhances IFN-γ production in a CMV T cell restimulation assay. Briefly, CMV⁺ human PBMCs were plated at 250,000 cells/well with isotype control antibody or with the A1.5 Ab and stimulated with 5 μg/mL CMV lysate for 4 days. Supernatant IFN-γ levels were measured by ELISA.
• As shown in FIGS. 33A and 33B, the activatable anti-PD1 antibody referred to herein as A1.5 PD34 2001 (i.e., VH of SEQ ID NO: 21, VL of SEQ ID NO: 47, masking moiety of SEQ ID NO: 99, and cleavable moiety of SEQ ID NO: 214) binds human PD1 with decreased affinity relative to the parental PD-1 Ab, i.e., A1.5 Ab (FIG. 33A), and the A1.5 PD34 2001 activatable antibody shows functional masking in a CMV T cell antigen recall assay (FIG. 33B). Briefly, 4 mg/mL of the A1.5 PD34 2001 activatable antibody was combined with 0 μg/mL or 60 μg/mL recombinant human urokinase (rh uPA, R&D, Cat. #1310-SE) and incubated at 37° C. overnight. Binding of the activatable antibody incubated with uPA to hPD1 was assayed by standard plate ELISA. As shown in FIG. 33, the activatable anti-PD1 antibodies of the disclosure regain full binding activated after activation by a protease.
Example 30. Pharmacokinetic Evaluation of Activatable Anti-Human PD1 Antibodies in Non-Human Primate Model
• This Example demonstrates pharmacokinetic and dose proportionality data for anti-PD-1 antibodies and anti-PD-1 activatable antibodies of the embodiments.
• Briefly, female cynomolgus monkeys (n=2/group) were dosed with a single IV bolus dose of either the A1.5 antibody or the activatable antibody referred to herein as A1.5 PD34 2001 at 1 mg/kg or at 5 mg/kg. Plasma samples were analyzed for A1.5 and A1.5 PD34 2001 concentrations by a qualified anti-human sandwich ELISA. The results are shown in FIG. 34, where each line represents one individual. Mean PK parameters shown for both A1.5 and A1.5 PD34 2001. Similar results were seen for activatable antibodies A1.5 PD34 2012 and A1.5 PD34 2011 administered to cynomolgus monkeys in a similar study.
Example 31. Activatable Anti-Mouse PD-1 J43 Antibodies Reduce Incidence of Diabetes in NOD Mice Dosed with Anti-CTLA4 Antibody
• In this Example, anti-PD-1 J43 activatable antibodies were analyzed for the ability to protect from anti-PD-1 induction of diabetes in NOD mice when dosed concurrently with anti-CTLA-4 9D9 mIgG2b antibody (BioXCell cat #BE0164). The NOD mice, substrain NOD/ShiLtJ, were obtained from Jackson Laboratory at 4 weeks and acclimated on site for 1 week. At 5 weeks, mice were checked for diabetes prior to enrollment, grouped, and dosed as set forth in Table 23. As used herein, the antibody referred to as “J43 m2a EN” (and variations thereof) comprises a heavy chain (HC) of SEQ ID NO: 546; a light chain (LC) of SEQ ID NO: 543; and a constant region of SEQ ID NO: 1516. As used herein, the activatable antibody referred to as “J43 MP8-2 2012 m2a EN” is an activatable antibody comprising the J43 m2a EN antibody, the MP8-2 masking moiety (SEQ ID NO: 549), and the 2012 substrate (SEQ ID NO: 1101), and the activatable antibody referred to as “J43 MP8-2 2001 m2a EN” is an activatable antibody comprising the J43 m2a EN antibody, the MP8-2 masking moiety (SEQ ID NO: 549), and the 2001 substrate (SEQ ID NO: 214).

• TABLE 23
  Dosing regimen

  Treatment

  Dose

  			Dose	Article	Dose	volume
  Group	Count	Article #1	(mg/kg)	#2	(mg/kg)	(mL/kg)	Schedule	Route

  1	8	mIgG1	10	mIgG2b	10	10	d0, d4, d7	IP
  		MOPC-21		MPC-11
  2	8	Anti-	10	mIgG1	10	10	d0, d4, d7	IP
  		CTLA4		MOPC-
  		9D9		21
  		mIgG2b
  3	8	Anti-PD-1	10	mIgG2b	10	10	d0, d4, d7	IP
  		(J43 m2a		MPC-11
  		EN)
  4	8	Anti-PD-1	1	mIgG2b	10	10	d0, d4, d7	IP
  		(J43 m2a		MPC-11
  		EN)
  5	8	Anti-PD-1	10	Anti-	10	10	d0, d4, d7	IP
  		(J43 m2a		CTLA4
  		EN)		9D9
  				mIgG2b
  6	8	Anti-PD-1	1	Anti-	10	10	d0, d4, d7	IP
  		(J43 m2a		CTLA4
  		EN)		9D9
  				mIgG2b
  7	8	J43 MP8-2	10	mIgG2b	10	10	d0, d4, d7	IP
  		2012 m2a		MPC-11
  		EN
  8	8	J43 MP8-2	10	Anti-	10	10	d0, d4, d7	IP
  		2012 m2a		CTLA4
  		EN		9D9
  				mIgG2b
  9	8	J43 MP8-2	10	mIgG2b	10	10	d0, d4, d7	IP
  		2001 m2a		MPC-11
  		EN
  10	8	J43 MP8-2	10	Anti-	10	10	d0, d4, d7	IP
  		2001 m2a		CTLA4
  		EN		9D9
  				mIgG2b

• FIG. 35 which plots % non-diabetic versus number of days post initial dose, shows that the combination of 10 mg/kg anti-PD-1 J43 antibody plus 10 mg/kg anti-CTLA-4 antibody dosed on days 0, 4 and 7 induced diabetes in 50% of NOD mice by day eleven while the same dosing schedule of activatable anti-PD-1 J43 antibodies with CTLA-4 antibody resulted in no induction of diabetes to day eighteen.
Example 32. Activatable Anti-Mouse PD1 J43 m2a EN Antibodies Show Enhanced Efficacy when Coadministered with Anti-CTLA4 Antibody in the MC38 Syngeneic Tumor Model
• This Example demonstrates that activatable antibodies of the embodiments are able to reduce the growth of MC38 syngeneic tumors as single agents and induce MC38 tumor regression when coadministered with anti-CTLA4 antibody 9D9 mIgG2b.
• In this Example, anti-PD1 activatable antibodies J43 MP8-2 2011 m2a EN and J43 MP8-2 2012 m2a EN were analyzed for the ability to slow the growth of or, in combination with anti-CTLA4 antibody, induce regression in MC38 syngeneic tumors. As used herein, the antibody referred to as “J43 m2a EN” (and variations thereof) comprises a heavy chain (HC) of SEQ ID NO: 546; a light chain (LC) of SEQ ID NO: 543; and a constant region of SEQ ID NO: 1516. As used herein, the activatable antibody referred to as “J43 MP8-2 2011 m2a EN” is an activatable antibody comprising the J43 m2a EN antibody, the MP8-2 masking moiety (SEQ ID NO: 549), and the 2011 substrate (SEQ ID NO: 1100), and the activatable antibody referred to as “J43 MP8-2 2012 m2a EN” is an activatable antibody comprising the J43 m2a EN antibody, the MP8-2 masking moiety (SEQ ID NO: 549), and the 2012 substrate (SEQ ID NO: 1101).
• The mouse colon carcinoma cell line MC38 was obtained from ATCC. MC38 cells were grown in RPMI-1640 supplemented with 10% fetal bovine serum at 37° C. in an atmosphere of 5% CO₂ in air. Cells were harvested during the logarithmic growth period, resuspended in PBS with proper cell concentration, and kept on ice for tumor induction.
• Each mouse was inoculated subcutaneously at the right flank with 1.5×10⁶ MC38 cells in PBS for tumor development. The treatments were started when the mean tumor size reached approximately 60 mm³ (45-80 mm³). Tumor sizes were measured twice weekly in two dimensions using a caliper, and the volume was expressed in mm³ using the formula: V=0.5 a×b² where a and b are the long and short diameters of the tumor, respectively.
• The mice were grouped and dosed as set forth in Table 24.

• TABLE 24
  				Dose
  			Dose	volume
  Group	Count	Treatment	(mg/kg)	(mL/kg)	Schedule	Route
  1	10	mIgG1 MOPC-21 +	10 + 10	10	b.i.w. for 3	IP
  		mIgG12b MPC-11			weeks
  2	10	Anti-CTLA4 9D9 mIgG2b	10	10	b.i.w. for 3	IP
  					weeks
  3	10	Anti-PD-1 (J43 m2a EN)	10	10	b.i.w. for 3	IP
  					weeks
  4	10	J43 MP8-2 2012 m2a EN	10	10	b.i.w. for 3	IP
  					weeks
  5	10	J43 MP8-2 2011 m2a EN	10	10	b.i.w. for 3	IP
  					weeks
  6	10	Anti-PD-1 (J43 m2a EN) +	10 + 10	10	b.i.w. for 3	IP
  		Anti-CTLA4 9D9 mIgG2b			weeks
  7	10	J43 MP8-2 2012 m2a EN +	10 + 10	10	b.i.w. for 3	IP
  		Anti-CTLA4 9D9 mIgG2b			weeks
  8	10	J43 MP8-2 2011 m2a EN +	10 + 10	10	b.i.w. for 3	IP
  		Anti-CTLA4 9D9 mIgG2b			weeks

• FIG. 36, which plots tumor volume versus number of days post initial dose, demonstrates that anti-PD1 activatable antibodies MP8-2 2012 m2a EN and MP8-2 2011 m2a EN inhibit the growth of MC38 syngeneic tumors similar to positive control anti-PD1 antibody J43 m2a EN both as single agents and in combination with anti-CTLA4 antibody 9D9 mIgG2b (BioXCell, West Lebanon, N.H.).
Example 33. Activatable Anti-Mouse PD1 J43 m2a EN Antibodies Show Durable Anti-Tumor Activity when Coadministered with Anti-CTLA4 Antibody in the MC38 Syngeneic Tumor Model
• This Example demonstrates anti-PD-1 activatable antibodies of the embodiments in combination with anti-CTLA4 antibodies induce durable anti-tumor complete responses in the MC38 syngeneic tumor model.
• In this Example, all animals treated with combinations of anti-CTLA4 and anti-PD1 agents from Example 28 that showed sustained tumor regression ((i) anti-PD-1 J43 m2aEN+anti-CTLA4 9D9 mIgG2b (referred to in FIG. 37 as “anti-PD-1 J43 m2aEN Antibody”+“anti-CTLA4 9D9 mIgG2b Antibody”) (n=8), (ii) activatable antibody anti-PD-1 J43 MP8-2 2012 m2a EN+anti-CTLA4 9D9 mIgG2b (referred to in FIG. 37 as “J43 MP8-2 2012 m2a EN AA”+“anti-CTLA4 9D9 mIgG2b Antibody” where AA stands for activatable antibody) (n=8), and activatable antibody anti-PD-1 J43 MP8-2 2011 m2a EN+anti-CTLA4 9D9 mIgG2b (referred to in FIG. 37 as “J43 MP8-2 2011 m2a EN AA”+“anti-CTLA4 9D9 mIgG2b Antibody” where AA stands for activatable antibody) (n=6)) were implanted at day 38 with 1.5×10⁶ MC38 tumor cells in the left flank opposite to the original MC38 implantation. Five untreated mice were implanted with 1.5×10⁶ MC38 tumor cells to confirm tumorigenic activity of the MC38 cells.
• FIG. 37 shows that no mice previously treated with combinations of anti-PD1 and anti-CTLA4 agents showed regrowth of the original tumor sites (right flank) or growth of new tumors (left flank) while all five of the untreated control mice showed rapid tumor growth.
Example 34. Activatable Anti-Mouse PD-1 J43 Antibodies Reduce Incidence of Diabetes in NOD Mice Co-Dosed with Anti-CTLA4 Antibody
• This Example demonstrates that anti-PD-1 activatable antibodies of the embodiments in combination with anti-CTLA4 antibodies protected NOD mice from PD1 m2a EN-mediated induction of diabetes.
• In this Example, anti-PD-1 J43 activatable antibody MP8-2 2011 m2aEN was analyzed for the ability to protect from anti-PD-1 induction of diabetes in NOD mice when dosed concurrently with anti-CTLA-4 9D9 mIgG2b antibody (BioXcell cat #BE0164). The NOD mice, substrain NOD/ShiLtJ, were obtained from Jackson Laboratory at 4 weeks and acclimated on site for 1 week. At 5 weeks, mice were checked for diabetes prior to enrollment, grouped, and dosed as set forth in Table 25.

• TABLE 25
  Dosing regimen

  Treatment

  Dose

  			Dose		Dose	volume
  Group	Count	Article #1	(mg/kg)	Article #2	(mg/kg)	(mL/kg)	Schedule	Route
  1	8	Anti-CTLA4	10	mIgG1	10	10	d0, d4, d7	IP
  		9D9 mIgG2b		MOPC-21
  2	8	Anti-PD-1 (J43	10	mIgG2b	10	10	d0, d4, d7	IP
  		m2a EN)		MPC-11
  3	8	Anti-PD-1 (J43	10	Anti-CTLA4	10	10	d0, d4, d7	IP
  		m2a EN)		9D9 mIgG2b
  4	8	J43 MP8-2	10	mIgG2b	10	10	d0, d4, d7	IP
  		2011 m2a EN		MPC-11
  5	8	J43 MP8-2	10	Anti-CTLA4	10	10	d0, d4, d7	IP
  		2011 m2a EN		9D9 mIgG2b

• FIG. 38, which plots % non-diabetic versus number of days post initial dose, shows that the single agent anti-PD-1 J43 antibody (referred to in the figure as “anti-PD1 J43 Ab”) and the combination of 10 mg/kg anti-PD-1 J43 antibody plus 10 mg/kg anti-CTLA4 antibody (referred to in the figure as “anti-PD1 J43 Ab”+“anti-CTLA4 9D9 mIgG2b”) dosed on days 0, 4 and 7 induced diabetes in 25% of NOD mice by day nine. In contrast, the same dosing schedule of activatable antibody anti-PD-1 J43 MP8-2 2011 m2a EN (referred to in the figure as “J43 MP8-2 2011 m2a EN AA” where AA stands for activatable antibody) as a single agent or in combination with anti-CTLA4 antibody (referred to in the figure as “J43 MP8-2 2011 m2a EN AA+“anti-CTLA4 9D9 mIgG2b” where AA stands for activatable antibody) resulted in no induction of diabetes to day fifteen.
Example 35. Anti-PD-1 Nivolumab Activatable Antibodies of the Embodiments are Functionally Masked in a Human T-Cell Restimulation Assay
• This Example describes the effect of masking moieties on the biological function of the anti-PD-1 nivolumab antibody.
• PBMCs from a CMV-positive donor (Hemacare) were plated at 2×10⁵ cells/well in the presence of CMV viral lysate (Astarte) and either anti-PD-1 antibody A1.5, anti-PD-1 activatable antibody A1.5 PD34 2001, anti-PD-1 antibody nivolumab (NV1), anti-PD-1 nivolumab activatable antibody NV1 NV07 2001, or an hIgG4 isotype control antibody. After four days, supernatant was removed from each well and IFN-gamma levels were assayed using an IFN-gamma ELISA kit (Life Technologies, Carlsbad, Calif.).
• FIG. 39 demonstrates that the anti-PD-1 activatable antibody A1.5 PD34 2001 (referred to in the figure as “A1.5 PD34 2001 AA” where AA stands for activatable antibody) and anti-PD1 nivolumab activatable antibody NV1 NV07 2001 (referred to in the figure as “NV1 NV07 2001 AA” where AA stands for activatable antibody) effected increased CMV-stimulated IFN-gamma secretion compared to the control hIgG4 antibody (referred to in the figure as hIgG4) but decreased potency relative to anti-PD-1 parental antibody A1.5 (referred to in the figure as A1.5) or anti-PD-1 parental antibody nivolumab (referred to in the figure as NV1).
Example 36. Anti-PD-1 Pembrolizumab Activatable Antibodies of the Embodiments are Functionally Masked in a Human T-Cell Restimulation Assay
• This example describes the effect of masking moieties on the biological function of the anti-PD-1 pembrolizumab antibody.
• PBMCs from a CMV-positive donor (Hemacare) were plated at 2×10⁵ cells/well in the presence of 4 ug/ml CMV viral lysate (Astarte) and either anti-PD-1 antibody A1.5, anti-PD-1 antibody pembrolizumab (PM1), anti-PD-1 pembrolizumab activatable antibody PM1 PM07 2001, or an hIgG4 isotype control antibody. After four days, supernatant was removed from each well and IFN-gamma levels were assayed using an IFN-gamma ELISA kit (Life Technologies, Carlsbad, Calif.).
• FIG. 40 demonstrates that anti-PD1 pembrolizumab activatable antibody PM1 PM07 2001 (referred to in the figure as “PM1 PM07 2001 AA” where AA stands for activatable antibody) effected increased CMV-stimulated IFN-gamma secretion compared to the control hIgG4 antibody (referred to in the figure as hIgG4) but decreased potency relative to anti-PD-1 parental antibody A1.5 (referred to in the figure as A1.5) or anti-PD-1 parental antibody pembrolizumab (referred to in the figure as PM1).
OTHER EMBODIMENTS
• While the invention has been described in conjunction with the detailed description thereof, the foregoing description is intended to illustrate and not limit the scope of the invention, which is defined by the scope of the appended claims. Other aspects, advantages, and modifications are within the scope of the following.

Claims (21)

1-99. (canceled)

100. An isolated antibody or antigen binding fragment thereof (AB) that specifically binds to a human PD-1, wherein the AB comprises:

a VH CDR1 amino acid sequence comprising GFTFSNYAMS SEQ ID NO: 655),

a VH CDR2 amino acid sequence comprising YISNGGGDTH (SEQ ID NO: 660),

a VH CDR3 amino acid sequence comprising ENYGTSPFVY (SEQ ID NO: 666),

a VL CDR1 amino acid sequence comprising RASESVDNYGIS (SEQ ID NO: 673),

a VL CDR2 amino acid sequence comprising AASNQGS (SEQ ID NO: 678), and

a VL CDR3 amino acid sequence comprising QQSKDVPWT (SEQ ID NO: 683).

101. An activatable antibody that, when activated, specifically binds to a human PD-1, wherein said activatable antibody comprises:

an antibody or an antigen binding fragment thereof (AB) that specifically binds to mammalian PD-1, wherein the AB comprises

a VH CDR1 amino acid sequence comprising GFTFSNYAMS SEQ ID NO: 655),

a VH CDR2 amino acid sequence comprising YISNGGGDTH (SEQ ID NO: 660),

a VH CDR3 amino acid sequence comprising ENYGTSPFVY (SEQ ID NO: 666),

a VL CDR1 amino acid sequence comprising RASESVDNYGIS (SEQ ID NO: 673),

a VL CDR2 amino acid sequence comprising AASNQGS (SEQ ID NO: 678), and

a VL CDR3 amino acid sequence comprising QQSKDVPWT (SEQ ID NO: 683);

a masking moiety (MM) that inhibits the binding of the AB to mammalian PD-1 when the activatable antibody is in an uncleaved state; and

a cleavable moiety (CM) coupled to the AB, wherein the CM is a polypeptide that functions as a substrate for a protease,

wherein the MM is coupled to the AB via the CM.

102. The activatable antibody of claim 101, wherein the AB specifically blocks a human PD-L1 and a human PD-L2 from binding to the human PD-1.

103. The activatable antibody of claim 101, wherein the activatable antibody in an uncleaved state specifically binds to the human PD-1 with a dissociation constant of 0.5 nM to 1 nM.

104. The activatable antibody of claim 101, wherein the CM is a substrate for a protease that is active in diseased tissue.

105. A pharmaceutical composition comprising the activatable antibody of claim 101 and a carrier.

106. An isolated nucleic acid molecule encoding the activatable antibody of claim 101.

107. A vector comprising the isolated nucleic acid molecule of claim 106.

108. A method of producing an activatable antibody by culturing a cell under conditions that lead to expression of the activatable antibody, wherein the cell comprises the nucleic acid molecule of claim 106.

109. A method of reducing binding of a ligand selected from the group consisting of PD-L1 or PD-L2 to PD-1 on T cells comprising administering an effective amount of the activatable antibody of claim 101 to a subject in need thereof.

110. A method of reducing immune suppression mediated by engagement of PD-1 on T cells to PD-L1 or PD-L2 on tumor or other immune cells, the method comprising administering to a subject in need thereof a therapeutically effective amount of the activatable antibody of claim 101.

111. A method of treating, alleviating a symptom of, or delaying the progression of a cancer comprising administering to a subject in need thereof a therapeutically effective amount of the activatable antibody of claim 101.

112. The activatable antibody of claim 101, wherein the activatable antibody comprises a heavy chain that comprises an IgG4 amino acid sequence.

113. The activatable antibody of claim 101, wherein the AB comprises a VH comprising the amino acid sequence of SEQ ID NO: 33.

114. The activatable antibody of claim 101, wherein the AB comprises a VL comprising the amino acid sequence of SEQ ID NO: 41.

115. The activatable antibody of claim 101, wherein the MM comprises an amino acid sequence selected from the group consisting of SEQ ID NOs: 66-213, 384-514, and 548-571.

116. The activatable antibody of claim 101, wherein the CM comprises an amino acid sequence selected from the group consisting of SEQ ID NOs: 214, 294-361, 1092-1112, 1157, 1158, 1161, 1162, 1165, 1166, 1169, 1520, and 1695-1704.

117. The activatable antibody of claim 101, wherein the AB has one or more of the characteristics selected from the group consisting of:

(a) the AB is an antigen binding fragment selected from the group consisting of a Fab fragment, a F(ab′)2 fragment, a scFv, a scAb, a dAb, a single domain heavy chain antibody, and a single domain light chain antibody;

(b) the AB is a monoclonal antibody;

(c) the AB is linked to the CM;

(d) the AB is linked directly to the CM; and

(e) the AB is linked to the CM via a linking peptide.

118. A conjugated activatable antibody comprising the activatable antibody of claim 101 conjugated to an agent.

119. The conjugated activatable antibody of claim 118, wherein the agent has one or more of the following characteristics selected from the group consisting of:

(a) the agent is conjugated to the activatable antibody via a linker;

(b) the agent is conjugated to the activatable antibody via a cleavable linker,

(c) the linker is conjugated to the activatable antibody via a non-cleavable linker;

(d) the agent is a detectable moiety; and

(e) the agent is a diagnostic agent.

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