AU2013205086A1 - Treatment of mucositis with kallikrein inhibitors - Google Patents

Abstract

Treatment of Mucositis with Kallikrein Inhibitors Abstract Methods, kits and compositions are disclosed that include an isolated kallikrein inhibitor for the treatment of mucositis.

Description

Treatment of Mucositis with Kallikrein Inhibitors CROSS REFERENCE TO RELATED APPLICATIONS This application claims priority to U.S. Application Serial No. 61/142,746, filed on January 6, 2009. The disclosure of the prior application is considered part of (and is 5 incorporated by reference in) the disclosure of this application. BACKGROUND Mucositis is a common serious side effect of high-dose chemotherapy (CT) and/or radiotherapy (RT) regimens often manifested as erythema and painful ulcerative lesions 10 of the mouth, esophagus, pharynx and gastrointestinal tract that threatens the successful treatment of at least 600,000 people worldwide. These cytoreductive therapies aimed at killing cancer cells can also indiscriminately destroy other fast-growing cells such as the lining of the mouth and throat and gastrointestinal tract. The development of mucositis is a complex process. Typically, mucositis 15 symptoms develop 5 to 8 days following the administration of CT and last approximately 7 to 14 days. The pathobiology of mucositis is currently defined as a 5-phase process: initiation, signaling with generation of messengers, amplification, ulceration, and, finally, healing. Oral and gastrointestinal (GI) mucositis can affect up to 100% of patients 20 undergoing high-dose chemotherapy and hematopoietic stem cell transplantation (HSCT), 80% of patients with malignancies of the head and neck receiving radiotherapy, and a wide range of patients receiving chemotherapy. For most cancer treatments, about 5-15% of patients get mucositis. However, with 5-fluorouracil (5-FU), up to 40% get mucositis, and 10-15% get grade 3-4 oral mucositis. Irinotecan treatment is associated 25 with severe GI mucositis in over 20% of patients. 75-85% of bone marrow transplantation recipients experience mucositis, of which oral mucositis is the most common and most debilitating, especially when melphalan is used. In grade 3 oral mucositis, the patient is unable to eat solid food, and in grade 4, the patient is unable to consume liquids either. Radiotherapy to the head and neck or to the pelvis or abdomen is 1/151 associated with grade 3 and grade 4 oral or GI mucositis, respectively, often exceeding 50% of patients. Among patients undergoing head and neck radiotherapy, pain and decreased oral function may persist long after the conclusion of therapy. Fractionated radiation dosage increases the risk of mucositis to > 70% of patients in most trials. 5 Oral mucositis has been identified as the most debilitating side effect of anticancer therapy by patients who experienced it while undergoing myelotoxic therapy for hematopoietic stem cell transplant, which is associated with the greatest degree of mucosal toxicity with 70%-80% of patients suffering from oral mucositis. Consequent morbidities of severe oral mucositis can include pain severe enough to require opioid 10 analgesia, difficulty or inability to swallow due to ulcerations in the mouth and throat, which, if severe, may necessitate total parenteral nutrition (TPN) and rehydration, difficulty or inability to talk, which can hinder patients' abilities to communicate. Of significance, the development of oral mucositis often precludes oncologists from prescribing a full dose and regimen of chemotherapy or radiation therapy so that the 15 disease frequently limits the potential full benefit of possibly curative treatments. The burden of oral mucositis development has been estimated to add $4,000 to hospital costs for patients with head and neck cancers to $43,000 for undergoing patients bone marrow transplant. Managing oral mucositis is primarily supportive. There are many different 20 methods to help relieve the pain, including sucking on ice cubes, antioxidants, and mouth rinses. Several mouth rinses are available that combine antihistamines, anesthetics, anti inflammatory medications (such as corticosteroids), antibiotics, and antifungals. Narcotic analgesics may also prove to help relieve the pain. Other methods include antimicrobials, anti-inflammatories, and good oral care. 25 Palifermin (KEPIVANCE@) (human keratinocyte growth factor (KGF)) is the only drug approved for oral mucositis and is indicated to decrease the incidence and duration of severe oral mucositis in patients with hematologic malignancies receiving myelotoxic therapy requiring hematopoietic stem cell support/transplantation. However, HSCT represents a small subset of the cancer population and most solid tumors carry 30 KGF receptors, through which this agent might have potentially undersired agonist effect. Thus, application of palifermin (KEPIVANCE@) to the larger market of cancers and 2/151 consequent oral mucositis resulting from treatment thereof is extremely unlikely. Additional indication studies beyond HSCT are currently being done, and include use of the drug in graft versus host disease, head and neck cancers, Stage 2/3 colon cancer multiple myeloma, lymphoma and leukemia, and pediatric HSCT populations. 5 Thus, there remains a significant unmet need in the treatment of mucositis. SUMMARY Disclosed herein are methods for the treatment of mucositis, in particular oral mucositis. In one aspect, the invention provides methods for the treatment of mucositis comprising administration of a therapeutically effective amount of an isolated inhibitor of 10 kallikrein, optionally in combination with another agent, such as palifermin (KEPIVANCE@) (human keratinocyte growth factor (KGF)). The methods described herein include administering an effective amount of the kallikrein inhibitor. Such an amount can be an amount sufficient to produce a detectable improvement, to reduce or ameliorate at least one symptom, to modulate (e.g., improve) at least one physiological 15 parameter, or to prevent the development of more severe grades of the illness to a statistically significant degree. Disclosed herein are methods for preventing mucositis, in particular oral mucositis. In one aspect, the invention provides methods for the prevention of mucositis (e.g., in a subject at risk of developing mucositis) comprising administration of a 20 prophylactically effective amount of an isolated inhibitor of kallikrein, optionally in combination with another agent, such as palifermin (KEPIVANCE@) (human keratinocyte growth factor (KGF)). The methods described herein include administering an effective amount of the kallikrein inhibitor. Such an amount can be an amount sufficient to reduce or delay or ameliorate at least one symptom or one physiological 25 parameter. A subject (e.g., patient) who is at risk for developing mucositis can be, e.g., a subject who will be undergoing, is undergoing, or will be undergoing a chemotherapy (e.g., high-dose chemotherapy) and/or radiotherapy regimen. As another example, a subject (e.g., patient) who is at risk for developing mucositis can be, e.g., a subject who has been diagnosed with cancer, e.g., cancer of the head or neck. 3/151 The kallikrein inhibitor useful in the methods, compositions and kits may be, e.g., a plasma kallikrein (pKal) or tissue kallikrein inhibitor. In some embodiments, the inhibitor is a plasma kallikrein inhibitor. The kallikrein inhibitors useful in the methods, compositions and kits may be any 5 of the Kunitz domain polypeptides described herein, larger polypeptides comprising any such Kunitz domains, provided the kallikrein inhibitor polypeptides bind and inhibit kallikrein as determined in standard assays, kallikrein binding proteins (e.g., antibodies, e.g., anti-plasma kallikrein antibodies), or other kallikrein inhibitors described herein. In some embodiments, the kallikrein inhibitor comprises or consists of the amino 10 acid sequence Glu Ala Met His Ser Phe Cys Ala Phe Lys Ala Asp Asp Gly Pro Cys Arg Ala Ala His Pro Arg Trp Phe Phe Asn Ile Phe Thr Arg Gln Cys Glu Glu Phe Ile Tyr Gly Gly Cys Glu Gly Asn Gln Asn Arg Phe Glu Ser Leu Glu Glu Cys Lys Lys Met Cys Thr Arg Asp (SEQ ID NO:2), or a fragment thereof, such as amino acids 3-60 of SEQ ID NO:2. 15 In some embodiments, the kallikrein inhibitor comprises or consists of the amino acid sequence Met His Ser Phe Cys Ala Phe Lys Ala Asp Asp Gly Pro Cys Arg Ala Ala His Pro Arg Trp Phe Phe Asn Ile Phe Thr Arg Gln Cys Glu Glu Phe Ile Tyr Gly Gly Cys Glu Gly Asn Gln Asn Arg Phe Glu Ser Leu Glu Glu Cys Lys Lys Met Cys Thr Arg Asp (amino acids 3-60 of SEQ ID NO:2). 20 In some embodiments, the kallikrein inhibitor comprises a plasma kallikrein binding protein (e.g., antibody, e.g., an anti- plasma kallikrein antibody described herein). In some embodiments, the binding protein (e.g., antibody, e.g., human antibody) binds the same epitope or competes for binding with a protein described herein. In some embodiments, the protein described herein is selected from the group 25 consisting of M162-A04, M160-G12, M142-H08, X63-G06, X81-B01, X67-D03, and X67-G04. In some embodiments, the plasma kallikrein binding protein competes with or binds the same epitope as X81-BO1. In some embodiments, the plasma kallikrein binding protein competes with or 30 binds the same epitope as X67-D03. 4/151 In some embodiments, the plasma kallikrein binding protein does not bind prekallikrein (e.g., human prekallikrein), but binds to the active form of plasma kallikrein (e.g., human plasma kallikrein). In certain embodiments, the protein binds at or near the active site of the catalytic 5 domain of plasma kallikrein, or a fragment thereof, or binds an epitope that overlaps with the active site of plasma kallikrein. In some embodiments, the protein binds to one or more amino acids that form the catalytic triad of plasma kallikrein: His434, Asp483, and/or Ser578 (numbering based on the human sequence). 10 In some embodiments, the protein binds to one or more amino acids of Ser479, Tyr563, and/or Asp585 (numbering based on the human sequence). In some embodiments, the plasma kallikrein binding protein decreases Factor XIIa and/or bradykinin production by greater than about 5%, about 10%, about 15%, about 20%, about 25%, about 30%, about 35%, about 40%, about 45%, about 50%, about 15 55%, about 60%, about 65%, about 70%, about 75%, about 80%, about 85%, about 90%, or about 95% as compared to a standard, e.g., the Factor XIIa and/or bradykinin production under the same conditions but in the absence of the protein. In some embodiments, the plasma kallikrein binding protein has an apparent inhibition constant (Ki,app) of less than 1000, 500, 100, or 10 nM. 20 In one embodiment, the HC and LC variable domain sequences are components of the same polypeptide chain. In another embodiment, the HC and LC variable domain sequences are components of different polypeptide chains. For example, the plasma kallikrein binding protein is an IgG., e.g., IgGI, IgG2, IgG3, or IgG4. The plasma kallikrein binding 25 protein can be a soluble Fab (sFab). In other implementations the plasma kallikrein binding protein includes a Fab2', scFv, minibody, scFv::Fc fusion, Fab::HSA fusion, HSA::Fab fusion, Fab::HSA::Fab fusion, or other molecule that comprises the antigen combining site of one of the binding proteins herein. The VH and VL regions of these Fabs can be provided as IgG, Fab, 30 Fab2, Fab2', scFv, PEGylated Fab, PEGylated scFv, PEGylated Fab2, 5/151 VH::CH1::HSA+LC, HSA::VH::CH1+LC, LC::HSA + VH::CH1, HSA::LC + VH::CH1, or other appropriate construction. In one embodiment, the plasma kallikrein binding protein is a human or humanized antibody or is non-immunogenic in a human. For example, the protein 5 includes one or more human antibody framework regions, e.g., all human framework regions. In one embodiment, the plasma kallikrein binding protein includes a human Fc domain, or an Fc domain that is at least 95, 96, 97, 98, or 99% identical to a human Fc domain. 10 In one embodiment, the plasma kallikrein binding protein is a primate or primatized antibody or is non-immunogenic in a human. For example, the protein includes one or more primate antibody framework regions, e.g., all primate framework regions. In one embodiment, the plasma kallikrein binding protein includes a primate Fc 15 domain, or an Fc domain that is at least 95, 96, 97, 98, or 99% identical to a primate Fc domain. "Primate" includes humans (Homo sapiens), chimpanzees (Pan troglodytes and Pan paniscus (bonobos)), gorillas (Gorilla gorilla), gibons, monkeys, lemurs, aye-ayes (Daubentonia madagascariensis), and tarsiers. In one embodiment, the plasma kallikrein binding protein includes human 20 framework regions, or framework regions that are at least 95, 96, 97, 98, or 99% identical to human framework regions. In certain embodiments, the plasma kallikrein binding protein includes no sequences from mice or rabbits (e.g., is not a murine or rabbit antibody). In some embodiments, the mucositis is selected from the group consisting of oral, 25 esophageal, pharyngeal and gastrointestinal mucositis. In some embodiments, the mucositis is oral mucositis. In some embodiments, the method further comprises administering palifermin. In some embodiments, the binding protein (e.g., antibody, e.g., human antibody) 30 comprisesg a heavy chain immunoglobulin variable domain sequence and a light chain immunoglobulin variable domain sequence, wherein: 6/151 the heavy chain immunoglobulin variable domain sequence comprises one, two, or three (e.g., three) CDR regions from the heavy chain variable domain of a protein described herein, and/or the light chain immunoglobulin variable domain sequence comprises one, two, or 5 three (e.g., three) CDR regions from the light chain variable domain of a protein described herein, wherein the protein binds to (e.g., and inhibits) plasma kallikrein. In some embodiments, the heavy chain immunoglobulin variable domain sequence comprises one, two, or three (e.g., three) CDR regions from the heavy chain 10 variable domain of M162-A04, M160-G12, M142-H08, X63-G06, X81-B01, X67-D03, or X67-G04, and/or the light chain immunoglobulin variable domain sequence comprises one, two, or three (e.g., three) CDR regions from the light chain variable domain of M162-A04, M160-G12, M142-H08, X63-G06, X81-B01, X67-D03, or X67-G04 (respectively). 15 In some embodiments, the one, two, or three (e.g., three) CDR regions from the heavy chain variable domain are from X81-BO1 and/or the one, two, or three (e.g., three) CDR regions from the light chain variable domain are from X81-B01. In some embodiments, the one, two, or three (e.g., three) CDR regions from the heavy chain variable domain are from X67-D03 and/or the one, two, or three (e.g., three) 20 CDR regions from the light chain variable domain are from X67-D03. In some embodiments, the heavy chain immunoglobulin variable domain sequence comprises the heavy chain variable domain of a protein described herein, and/or the light chain immunoglobulin variable domain sequence comprises the light chain variable domain of a protein described herein. 25 In some embodiments, the heavy chain immunoglobulin variable domain sequence comprises the heavy chain variable domain of M162-A04, M160-G12, M142 H08, X63-G06, X81-B01, X67-D03, or X67-G04, and/or the light chain immunoglobulin variable domain sequence comprises the light chain variable domain of M162-A04, M160-G12, M142-H08, X63-G06, X81-B01, X67-D03, or X67-G04 (respectively). 30 In some embodiments, the heavy chain immunoglobulin variable domain sequence comprises the heavy chain variable domain of X81-B01, and/or the light chain 7/151 immunoglobulin variable domain sequence comprises the light chain variable domain of X81-B01. In some embodiments, the heavy chain immunoglobulin variable domain sequence comprises the heavy chain variable domain of X67-D03, and/or the light chain 5 immunoglobulin variable domain sequence comprises the light chain variable domain of X67-D03. In some embodiments, the protein comprises the heavy chain of a protein described herein, and/or the light chain of a protein described herein. In some embodiments, the protein comprises the heavy chain of M162-A04, 10 M160-G12, M142-H08, X63-G06, X81-B01, X67-D03, or X67-G04, and/or the light chain of M162-A04, M160-G12, M142-H08, X63-G06, X81-B01, X67-D03, or X67-G04 (respectively). In some embodiments, the protein comprises the heavy chain of X81-B01, and/or the light chain of X81-B01. 15 In some embodiments, the protein comprises the heavy chain of X67-D03, and/or the light chain of X67-D03. In some embodiments, the protein includes one or more of the following characteristics: (a) a human CDR or human framework region; (b) the HC immunoglobulin variable domain sequence comprises one or more (e.g., 1, 2, or 3) CDRs 20 that are at least 85, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, or 100% identical to a CDR of a HC variable domain described herein; (c) the LC immunoglobulin variable domain sequence comprises one or more (e.g., 1, 2, or 3) CDRs that are at least 85, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, or 100% identical to a CDR of a LC variable domain described herein; (d) the LC immunoglobulin variable domain sequence is at 25 least 85, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, or 100% identical to a LC variable domain described herein (e.g., overall or in framework regions or CDRs); (e) the HC immunoglobulin variable domain sequence is at least 85, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, or 100% identical to a HC variable domain described herein (e.g., overall or in framework regions or CDRs); (f) the protein binds an epitope bound by a protein 30 described herein, or competes for binding with a protein described herein; (g) a primate CDR or primate framework region; (h) the HC immunoglobulin variable domain 8/151 sequence comprises a CDR1 that differs by at least one amino acid but by no more than 2 or 3 amino acids from the CDR1 of a HC variable domain described herein; (i) the HC immunoglobulin variable domain sequence comprises a CDR2 that differs by at least one amino acid but by no more than 2, 3, 4, 5, 6, 7, or 8 amino acids from the CDR2 of a HC 5 variable domain described herein; (j) the HC immunoglobulin variable domain sequence comprises a CDR3 that differs by at least one amino acid but by no more than 2, 3, 4, 5, or 6 amino acids from the CDR3 of a HC variable domain described herein; (k) the LC immunoglobulin variable domain sequence comprises a CDR1 that differs by at least one amino acid but by no more than 2, 3, 4, or 5 amino acids from the CDR1 of a LC variable 10 domain described herein; (1) the LC immunoglobulin variable domain sequence comprises a CDR2 that differs by at least one amino acid but by no more than 2, 3, or 4 amino acids from the CDR2 of a LC variable domain described herein; (m) the LC immunoglobulin variable domain sequence comprises a CDR3 that differs by at least one amino acid but by no more than 2, 3, 4, or 5 amino acids from the CDR3 of a LC variable 15 domain described herein ; (n) the LC immunoglobulin variable domain sequence differs by at least one amino acid but by no more than 2, 3, 4, 5, 6, 7, 8, 9, or 10 amino acids from a LC variable domain described herein (e.g., overall or in framework regions or CDRs); and (o) the HC immunoglobulin variable domain sequence differs by at least one amino acid but by no more than 2, 3, 4, 5, 6, 7, 8, 9, or 10 amino acids from a HC 20 variable domain described herein (e.g., overall or in framework regions or CDRs). In some embodiments, the protein has an apparent inhibition constant (Ki,app) of less than 1000, 500, 100, or 10 nM. In a preferred embodiment, the protein is an antibody (e.g., a human antibody) having the light and heavy chains of antibodies selected from the group consisting of 25 M162-A04, M160-G12, M142-H08, X63-G06, X81-B01, X67-D03, and X67-G04. In a preferred embodiment, the protein is an antibody (e.g., a human antibody) having the heavy chain of an antibody selected from the group consisting of: M162-A04, M160-G12, M142-H08, X63-G06, X81-B01, X67-D03, and X67-G04. In a preferred embodiment, the protein is an antibody (e.g., a human antibody) 30 having the light chain of an antibody selected from the group consisting of: M162-A04, M160-G12, M142-H08, X63-G06, X81-B01, X67-D03, and X67-G04. 9/151 In a preferred embodiment, the protein is an antibody (e.g., a human antibody) having light and heavy antibody variable regions of an antibody selected from the group consisting of M162-A04, M160-G12, M142-H08, X63-G06, X81-B01, X67-D03, and X67-G04. 5 In a preferred embodiment, the protein is an antibody (e.g., a human antibody) having a heavy chain antibody variable region of an antibody selected from the group consisting of: M162-A04, M160-G12, M142-H08, X63-G06, X81-B01, X67-D03, and X67-G04. In a preferred embodiment, the protein is an antibody (e.g., a human antibody) 10 having a light chain antibody variable region of an antibody selected from the group consisting of: M162-A04, M160-G12, M142-H08, X63-G06, X81-B01, X67-D03, and X67-G04. In a preferred embodiment, the protein is an antibody (e.g., a human antibody) having one or more (e.g., 1, 2, or 3) heavy chain CDRs selected from the corresponding 15 CDRs of the group of heavy chains consisting of M162-A04, M160-G12, M142-H08, X63-G06, X81-B01, X67-D03, and X67-G04. In a preferred embodiment, the protein is an antibody (e.g., a human antibody) having one or more (e.g., 1, 2, or 3) light chain CDRs selected from the corresponding CDRs of the group of light chains consisting of M162-A04, M160-G12, M142-H08, 20 X63-G06, X81-B01, X67-D03, and X67-G04. In a preferred embodiment, the protein is an antibody (e.g., a human antibody) having one or more (e.g., 1, 2, or 3) heavy chain CDRs selected from the corresponding CDRs of the group of heavy chains consisting of M162-A04, M160-G12, M142-H08, X63-G06, X81-B01, X67-D03, and X67-G04 and one or more (e.g., 1, 2, or 3) light chain 25 CDRs selected from the corresponding CDRs of the group of light chains consisting of M162-A04, M160-G12, M142-H08, X63-G06, X81-B01, X67-D03, and X67-G04 (respectively). In a preferred embodiment, the protein is an antibody (e.g., a human antibody) having the light and heavy chains of X81-B01. 30 In a preferred embodiment, the protein is an antibody (e.g., a human antibody) having the heavy chain of X81-BO1. 10/151 In a preferred embodiment, the protein is an antibody (e.g., a human antibody) having the light chain of X81-B01. In a preferred embodiment, the protein is an antibody (e.g., a human antibody) having light and heavy antibody variable regions of an antibody selected from X81-B01. 5 In a preferred embodiment, the protein is an antibody (e.g., a human antibody) having a heavy chain antibody variable region of X8 13-B0 1. In a preferred embodiment, the protein is an antibody (e.g., a human antibody) having a light chain antibody variable region of X8 13-B0 1. In a preferred embodiment, the protein is an antibody (e.g., a human antibody) 10 having one or more (e.g., 1, 2, or 3) heavy chain CDRs from the corresponding CDRs of the heavy chain of X81-B01. In a preferred embodiment, the protein is an antibody (e.g., a human antibody) having one or more (e.g., 1, 2, or 3) light chain CDRs from the corresponding CDRs of the light chain of X81-B01. 15 In a preferred embodiment, the protein is an antibody (e.g., a human antibody) having one or more (e.g., 1, 2, or 3) heavy chain CDRs from the heavy chain of X81-B01 and one or more (e.g., 1, 2, or 3) light chain CDRs from the corresponding CDRs of the light chain of X81-BO1. In a preferred embodiment, the protein is an antibody (e.g., a human antibody) 20 having the light and heavy chains of X67-D03. In a preferred embodiment, the protein is an antibody (e.g., a human antibody) having the heavy chain of X67-D03. In a preferred embodiment, the protein is an antibody (e.g., a human antibody) having the light chain of X67-D03. 25 In a preferred embodiment, the protein is an antibody (e.g., a human antibody) having light and heavy antibody variable regions of an antibody selected from X67-D03. In a preferred embodiment, the protein is an antibody (e.g., a human antibody) having a heavy chain antibody variable region of X67-D03. In a preferred embodiment, the protein is an antibody (e.g., a human antibody) 30 having a light chain antibody variable region of X67-D03. 11/151 In a preferred embodiment, the protein is an antibody (e.g., a human antibody) having one or more (e.g., 1, 2, or 3) heavy chain CDRs from the corresponding CDRs of the heavy chain of X67-D03. In a preferred embodiment, the protein is an antibody (e.g., a human antibody) 5 having one or more (e.g., 1, 2, or 3) light chain CDRs from the corresponding CDRs of the light chain of X67-D03. In a preferred embodiment, the protein is an antibody (e.g., a human antibody) having one or more (e.g., 1, 2, or 3) heavy chain CDRs from the heavy chain of X67-D03 and one or more (e.g., 1, 2, or 3) light chain CDRs from the corresponding CDRs of the 10 light chain of X67-D03. In some embodiments, the plasma kallikrein binding protein does not bind prekallikrein (e.g., human prekallikrein), but binds to the active form of plasma kallikrein (e.g., human plasma kallikrein). In some embodiments, the plasma kallikrein binding protein decreases Factor 15 XIIa and/or bradykinin production by greater than 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%, or about 95% as compared to a standard, e.g., the Factor XIIa and/or bradykinin production under the same conditions but in the absence of the protein. 20 In some embodiments, the plasma kallikrein binding protein has an apparent inhibition constant (Ki,app) of less than 1000, 500, 100, or 10 nM. In one embodiment, the HC and LC variable domain sequences are components of the same polypeptide chain. In another embodiment, the HC and LC variable domain sequences are 25 components of different polypeptide chains. For example, the protein is an IgG., e.g., IgGI, IgG2, IgG3, or IgG4. The protein can be a soluble Fab (sFab). In other implementations the protein includes a Fab2', scFv, minibody, scFv::Fc fusion, Fab::HSA fusion, HSA::Fab fusion, Fab::HSA::Fab fusion, or other molecule that comprises the antigen combining site of one of the binding proteins herein. The VH and 30 VL regions of these Fabs can be provided as IgG, Fab, Fab2, Fab2', scFv, PEGylated Fab, 12/151 PEGylated scFv, PEGylated Fab2, VH::CH1::HSA+LC, HSA::VH::CH1+LC, LC::HSA + VH::CH1, HSA::LC + VH::CH1, or other appropriate construction. In one embodiment, the protein is a human or humanized antibody or is non immunogenic in a human. For example, the protein includes one or more human 5 antibody framework regions, e.g., all human framework regions. In one embodiment, the protein includes a human Fc domain, or an Fc domain that is at least 95, 96, 97, 98, or 99% identical to a human Fc domain. In one embodiment, the protein is a primate or primatized antibody or is non immunogenic in a human. For example, the protein includes one or more primate 10 antibody framework regions, e.g., all primate framework regions. In one embodiment, the protein includes a primate Fc domain, or an Fc domain that is at least 95, 96, 97, 98, or 99% identical to a primate Fc domain. "Primate" includes humans (Homo sapiens), chimpanzees (Pan troglodytes and Pan paniscus (bonobos)), gorillas (Gorilla gorilla), gibons, monkeys, lemurs, aye-ayes (Daubentonia 15 madagascariensis), and tarsiers. In one embodiment, the protein includes human framework regions, or framework regions that are at least 95, 96, 97, 98, or 99% identical to human framework regions. In certain embodiments, the protein includes no sequences from mice or rabbits (e.g., is not a murine or rabbit antibody). 20 In some embodiments, the mucositis is selected from the group consisting of oral, esophageal, pharyngeal and gastrointestinal mucositis. In some embodiments, the mucositis is oral mucositis. In some embodiments, the method further comprises administering palifermin. 25 In one aspect, the invention provides a kit for the treatment of mucositis. The kit includes an isolated inhibitor of kallikrein, and instructions for administering the inhibitor to a subject (e.g., patient) having mucositis or who is at risk for developing mucositis. In one embodiment, the kit further includes instructions for administration of an additional therapeutic for the treatment of mucositis (e.g., perlifermin), and may optionally contain 30 the additional therapeutic. In one embodiment, the instructions provide a dosing regimen, dosing schedule, and/or route of administration of the inhibitor of kallikrein that 13/151 differs from the dosing regimen, dosing schedule and/or route of administration for the inhibitor in the absence of the additional therapeutic. A subject (e.g., patient) who is at risk for developing mucositis can be, e.g., a subject who will be undergoing, is undergoing, or will be undergoing a chemotherapy (e.g., high-dose chemotherapy) and/or 5 radiotherapy regimen. As another example, a subject (e.g., patient) who is at risk for developing mucositis can be, e.g., a subject who has been diagnosed with cancer, e.g., cancer of the head or neck. In some embodiments, the mucositis is selected from the group consisting of oral, esophageal, pharyngeal and gastrointestinal mucositis. 10 In some embodiments, the mucositis is oral mucositis. In some aspects, the disclosure features a kit, wherein the kit comprises: a container comprising a isolated kallikrein inhibitor; and instructions for use of said kallikrein inhibitor for the treatment of mucositis. 15 In some embodiments, the kit further comprises a container comprising palifermin. In some embodiments, the mucositis is selected from the group consisting of oral, esophageal, pharyngeal and gastrointestinal mucositis. In some embodiments, the mucositis is oral mucositis. 20 In some aspects, the disclosure features a composition comprising a therapeutically effective amount of the isolated kallikrein inhibitor described herein and a therapeutically effective amount of palifermin. 25 In another aspect, provided herein is the use of an isolated kallikrein inhibitor for the manufacture of a medicament for the treatment and/or prevention of mucositis. The details of one or more embodiments of the invention are set forth in the accompanying drawings and the description below. Other features, objects, and advantages of the invention will be apparent from the description and drawings, and from 30 the claims. 14/151 The contents of all references, pending patent applications and published patents, cited throughout this application are hereby expressly incorporated by reference. BRIEF DESCRIPTION OF THE FIGURES 5 FIGURE 1 shows a portion of a DNA and corresponding deduced amino acid for an exemplary kallikrein inhibitor polypeptide in plasmid pPIC-K503. The inserted DNA encodes the mata Prepro signal peptide of Saccharomyces cerevisiae (underlined) fused in frame to the amino terminus of the PEP-1 (DX-88) polypeptide having the amino acid sequence enclosed by the boxed area. The amino acid sequence of the PEP-I polypeptide 10 shown in the boxed region is SEQ ID NO:2, and the corresponding nucleotide coding sequence is SEQ ID NO:3. The dashed arrows indicate the location and direction of two PCR primer sequences in A OX regions that were used to produce sequencing templates. DNA sequence for the entire nucleotide sequence of the figure includes the structural coding sequence for the fusion protein and is designated SEQ ID NO:27. The double 15 underlined portion of the sequence indicates a diagnostic probe sequence. BstB I and EcoR I indicate locations of their respective palindromic, hexameric, restriction endonuclease sites in the sequence. Asterisks denote translational stop codons. See text for details. FIGURES 2A and 2B show an alignment of exemplary amino acid sequences, the 20 native LACI sequence from which these variants were derived (SEQ ID NO:32), and other known Kunitz domains (SEQ ID NOS:29-31 and 33-53). Cysteine residues are shown. FIGURE 3 depicts the alignment of the light chain DNA sequence of nongermlined (X63-G06) and germlined, codon optimized (X81-B01) versions of the 25 same antibody discovered using ROLIC affinity maturation. Positions indicated with an asterisk (*) are conserved, whereas blank spaces correspond to bases changed in X81 B01 due to either codon optimization or germlining. FIGURE 4 depicts the alignment of the light chain amino acid sequence of nongermlined (X63-G06) and germlined, codon optimized (X81-B01) versions of the 30 same antibody discovered using ROLIC affinity maturation. Positions indicated with an 15/151 asterisk (*) are conserved, whereas blank spaces correspond to amino acids changed in X81-B01 due to germlining. A total of 11 amino acids differ between the nongermlined (X63-G06) and germlined, codon optimized antibody (X81-B01). FIGURE 5 depicts the alignment of the heavy chain DNA sequence of 5 nongermlined (X63-G06) and germlined, codon optimized (X81-B01) versions of the same antibody discovered using ROLIC affinity maturation. Positions indicated with an asterisk (*) are conserved, whereas blank spaces correspond to DNA bases changed in X81-BO1 due to codon optimization. FIGURE 6 depicts the alignment of the heavy chain amino acid sequence of 10 nongermlined (X63-G06) and germlined, codon optimized (X81-B01) versions of the same antibody discovered using ROLIC affinity maturation. Positions indicated with an asterisk (*) are conserved. The two antibodies have the same amino acid sequence in the heavy chain. FIGURE 7A depicts the EPI-KAL2 competition for X81-B01 binding pKal. X81 15 BO (IgG) was captured on an anti-human Fc fragment specific surface of a CM5 BIACORE@ chip. pKal (100 nM) was flowed over the surface in the presence (lower sensorgram in the figure) or absence of 1 pM EPI-KAL2 (upper sensorgram in the figure). FIGURE 7B depicts the EPI-KAL2 competition for X67-D03 binding pKal. X67 20 D03 (IgG) was captured on an anti-human Fc fragment specific surface of a CM5 Biacore chip. pKal (100 nM) was flowed over the surface in the presence (lower sensorgram in the figure) or absence of 1 pM EPI-KAL2 (upper sensorgram in the figure). FIGURE 8 depicts the results of CLIPS epitope mapping for antibodies listed in Table 15. 25 FIGURES 9A-9C depict ClustalW alignment of pKal sequences from different species. Positions indicated by a "*" are conserved positions between, whereas positions indicated ":" indicate conservative substitutions between species. Positions indicated by a "." have nonconservative substitutions in some species. Stretches of amino acids indicated by the symbol "@" were shown to be highly solvent exposed by solvent 30 accessible surface area calculation. Stretches of amino acids indicated by a "+" were identified as potential epitopes of antibodies listed in Table 15. Amino acids highlighted 16/151 in grey were found by solvent accessible surface area calculation to be buried when complexed with a Kunitz domain active site inhibitor. The underlined positions are the amino acids that form the catalytic triad (His434, Asp483, and Ser578, numbering based on the human sequence). 5 DETAILED DESCRIPTION The inventors present herein new methods for the treatment of mucositis, for example, oral, esophageal, pharyngeal and/or gastrointestinal mucositis by the administration of an isolated kallikrein inhibitor. 10 Definitions For convenience, before further description of the present invention, certain terms employed in the specification, examples and appended claims are defined here. The singular forms "a", "an", and "the" include plural references unless the context clearly dictates otherwise. 15 The term "antibody" refers to a protein that includes at least one immunoglobulin variable domain or immunoglobulin variable domain sequence. For example, an antibody can include a heavy (H) chain variable region (abbreviated herein as VH), and a light (L) chain variable region (abbreviated herein as VL). In another example, an antibody includes two heavy (H) chain variable regions and two light (L) chain variable 20 regions. The term "antibody" encompasses antigen-binding fragments of antibodies (e.g., single chain antibodies, Fab and sFab fragments, F(ab') 2 , Fd fragments, Fv fragments, scFv, and domain antibodies (dAb) fragments (de Wildt et al., Eur J Immunol. 1996; 26(3):629-39.)) as well as complete antibodies. An antibody can have the structural features of IgA, IgG, IgE, IgD, IgM (as well as subtypes thereof). Antibodies may be 25 from any source, but primate (human and non-human primate) and primatized are preferred. The VH and VL regions can be further subdivided into regions of hypervariability, termed "complementarity determining regions" ("CDR"), interspersed with regions that are more conserved, termed "framework regions" ("FR"). The extent of the framework 30 region and CDRs has been precisely defined (see, Kabat, E.A., et al. (1991) Sequences of 17/151 Proteins of Immunological Interest, Fifth Edition, U.S. Department of Health and Human Services, NIH Publication No. 91-3242, and Chothia, C. et al. (1987) J. Mol. Biol. 196:901-917, see also www.hgmp.mrc.ac.uk). Kabat definitions are used herein. Each VH and VL is typically composed of three CDRs and four FRs, arranged from amino 5 terminus to carboxy-terminus in the following order: FRI, CDR1, FR2, CDR2, FR3, CDR3, FR4. The VH or VL chain of the antibody can further include all or part of a heavy or light chain constant region, to thereby form a heavy or light immunoglobulin chain, respectively. In one embodiment, the antibody is a tetramer of two heavy 10 immunoglobulin chains and two light immunoglobulin chains, wherein the heavy and light immunoglobulin chains are inter-connected by, e.g., disulfide bonds. In IgGs, the heavy chain constant region includes three immunoglobulin domains, CHI, CH2 and CH3. The light chain constant region includes a CL domain. The variable region of the heavy and light chains contains a binding domain that interacts with an antigen. The 15 constant regions of the antibodies typically mediate the binding of the antibody to host tissues or factors, including various cells of the immune system (e.g., effector cells) and the first component (Clq) of the classical complement system. The light chains of the immunoglobulin may be of types kappa or lambda. In one embodiment, the antibody is glycosylated. An antibody can be functional for antibody-dependent cytotoxicity and/or 20 complement-mediated cytotoxicity. One or more regions of an antibody can be human or effectively human. For example, one or more of the variable regions can be human or effectively human. For example, one or more of the CDRs can be human, e.g., HC CDR1, HC CDR2, HC CDR3, LC CDR1, LC CDR2, and LC CDR3. Each of the light chain CDRs can be 25 human. HC CDR3 can be human. One or more of the framework regions can be human, e.g., FRI, FR2, FR3, and FR4 of the HC or LC. For example, the Fc region can be human. In one embodiment, all the framework regions are human, e.g., have a sequence of a framework of an antibody produced by a human somatic cell, e.g., a hematopoietic cell that produces immunoglobulins or a non-hematopoietic cell. In one embodiment, the 30 human sequences are germline sequences, e.g., encoded by a germline nucleic acid. In one embodiment, the framework (FR) residues of a selected Fab can be converted to the 18/151 amino-acid type of the corresponding residue in the most similar primate germline gene, especially the human germline gene. One or more of the constant regions can be human or effectively human. For example, at least 70, 75, 80, 85, 90, 92, 95, 98, or 100% of an immunoglobulin variable domain, the constant region, the constant domains (CHI, CH2, 5 CH3, CLI), or the entire antibody can be human or effectively human. All or part of an antibody can be encoded by an immunoglobulin gene or a segment thereof. Exemplary human immunoglobulin genes include the kappa, lambda, alpha (IgA1 and IgA2), gamma (IgGI, IgG2, IgG3, IgG4), delta, epsilon and mu constant region genes, as well as the many immunoglobulin variable region genes. Full-length 10 immunoglobulin "light chains" (about 25 KDa or about 214 amino acids) are encoded by a variable region gene at the NH2-terminus (about 110 amino acids) and a kappa or lambda constant region gene at the COOH--terminus. Full-length immunoglobulin "heavy chains" (about 50 KDa or about 446 amino acids), are similarly encoded by a variable region gene (about 116 amino acids) and one of the other aforementioned 15 constant region genes, e.g., gamma (encoding about 330 amino acids). The length of human HC varies considerably because HC CDR3 varies from about 3 amino-acid residues to over 35 amino-acid residues. The term "antigen-binding fragment" of a full length antibody refers to one or more fragments of a full-length antibody that retain the ability to specifically bind to a 20 target of interest. Examples of binding fragments encompassed within the term "antigen binding fragment" of a full length antibody include (i) a Fab fragment, a monovalent fragment consisting of the VL, VH, CL and CHI domains; (ii) a F(ab') 2 fragment, a bivalent fragment including two Fab fragments linked by a disulfide bridge at the hinge region; (iii) a Fd fragment consisting of the VH and CHI domains; (iv) a Fv fragment 25 consisting of the VL and VH domains of a single arm of an antibody, (v) a dAb fragment (Ward et al., (1989) Nature 341:544-546), which consists of a VH domain; and (vi) an isolated complementarity determining region (CDR) that retains functionality. Furthermore, although the two domains of the Fv fragment, VL and VH, are coded for by separate genes, they can be joined, using recombinant methods, by a synthetic linker that 30 enables them to be made as a single protein chain in which the VL and VH regions pair to form monovalent molecules known as single chain Fv (scFv). See e.g., US patents 19/151 5,260,203, 4,946,778, and 4,881,175; Bird et al. (1988) Science 242:423-426; and Huston et al. (1988) Proc. Natl. Acad. Sci. USA 85:5879-5883. Antibody fragments can be obtained using any appropriate technique including conventional techniques known to those with skill in the art. The term "monospecific 5 antibody" refers to an antibody that displays a single binding specificity and affinity for a particular target, e.g., epitope. This term includes a "monoclonal antibody" or "monoclonal antibody composition," which as used herein refer to a preparation of antibodies or fragments thereof of single molecular composition, irrespective of how the antibody was generated. 10 The inhibition constant (Ki) provides a measure of inhibitor potency; it is the concentration of inhibitor required to reduce enzyme activity by half and is not dependent on enzyme or substrate concentrations. The apparent Ki (Ki,app) is obtained at different substrate concentrations by measuring the inhibitory effect of different concentrations of inhibitor (e.g., inhibitory binding protein) on the extent of the reaction (e.g., enzyme 15 activity); fitting the change in pseudo-first order rate constant as a function of inhibitor concentration to the Morrison equation (Equation 1) yields an estimate of the apparent Ki value. The Ki is obtained from the y-intercept extracted from a linear regression analysis of a plot of Ki,app versus substrate concentration. vvovL (Ki,app +1+ E)- (Ki,app +I+E) -4-. 20 Equation 1 Where v = measured velocity; vo = velocity in the absence of inhibitor; Ki,app apparent inhibition constant; I= total inhibitor concentration; and E = total enzyme concentration. 25 As used herein, "binding affinity" refers to the apparent association constant or Ka. The Ka is the reciprocal of the dissociation constant (KA). A binding protein may, for example, have a binding affinity of at least 105, 106, 107, 108, 109, 1010 and 1011 M- 1 for a particular target molecule. Higher affinity binding of a binding protein to a first target relative to a second target can be indicated by a higher Ka (or a smaller numerical value 20/151 Kd) for binding the first target than the Ka (or numerical value Kd) for binding the second target. In such cases, the binding protein has specificity for the first target (e.g., a protein in a first conformation or mimic thereof) relative to the second target (e.g., the same protein in a second conformation or mimic thereof; or a second protein). Differences in 5 binding affinity (e.g., for specificity or other comparisons) can be at least 1.5, 2, 3, 4, 5, 10, 15, 20, 37.5, 50, 70, 80, 91, 100, 500, 1000, or 105 fold. Binding affinity can be determined by a variety of methods including equilibrium dialysis, equilibrium binding, gel filtration, ELISA, surface plasmon resonance, or spectroscopy (e.g., using a fluorescence assay). Exemplary conditions for evaluating 10 binding affinity are in TRIS-buffer (50mM TRIS, 150mM NaCl, 5mM CaCl 2 at pH7.5). These techniques can be used to measure the concentration of bound and free binding protein as a function of binding protein (or target) concentration. The concentration of bound binding protein ([Bound]) is related to the concentration of free binding protein ([Free]) and the concentration of binding sites for the binding protein on the target where 15 (N) is the number of binding sites per target molecule by the following equation: [Bound] = N - [Free]/((1/Ka) + [Free]). It is not always necessary to make an exact determination of Ka, though, since sometimes it is sufficient to obtain a quantitative measurement of affinity, e.g., determined using a method such as ELISA or FACS analysis, is proportional to Ka, and 20 thus can be used for comparisons, such as determining whether a higher affinity is, e.g., 2-fold higher, to obtain a qualitative measurement of affinity, or to obtain an inference of affinity, e.g., by activity in a functional assay, e.g., an in vitro or in vivo assay. The term "binding protein" refers to a protein that can interact with a target molecule. This term is used interchangeably with "ligand." A "plasma kallikrein binding 25 protein" refers to a protein that can interact with (e.g., bind) plasma kallikrein, and includes, in particular, proteins that preferentially or specifically interact with and/or inhibit plasma kallikrein. A protein inhibits plasma kallikrein if it causes a decrease in the activity of plasma kallikrein as compared to the activity of plasma kallikrein in the absence of the protein and under the same conditions. In some embodiments, the plasma 30 kallikrein binding protein is an antibody. 21/151 The term "kallikrein inhibitor" refers to any agent or molecule that inhibits kallikrein. The term "combination" refers to the use of the two or more agents or therapies to treat the same patient, wherein the use or action of the agents or therapies overlap in time. 5 The agents or therapies can be administered at the same time (e.g., as a single formulation that is administered to a patient or as two separate formulations administered concurrently) or sequentially in any order. A "conservative amino acid substitution" is one in which the amino acid residue is replaced with an amino acid residue having a similar side chain. Families of amino acid 10 residues having similar side chains have been defined in the art. These families include amino acids with basic side chains (e.g., lysine, arginine, histidine), acidic side chains (e.g., aspartic acid, glutamic acid), uncharged polar side chains (e.g., glycine, asparagine, glutamine, serine, threonine, tyrosine, cysteine), nonpolar side chains (e.g., alanine, valine, leucine, isoleucine, proline, phenylalanine, methionine, tryptophan), beta 15 branched side chains (e.g., threonine, valine, isoleucine) and aromatic side chains (e.g., tyrosine, phenylalanine, tryptophan, histidine). It is possible for one or more framework and/or CDR amino acid residues of a binding protein to include one or more mutations (e.g., substitutions (e.g., conservative substitutions or substitutions of non-essential amino acids), insertions, or deletions) 20 relative to a binding protein described herein. A plasma kallikrein binding protein may have mutations (e.g., substitutions (e.g., conservative substitutions or substitutions of non-essential amino acids), insertions, or deletions) (e.g., at least one, two, three, or four, and/or less than 15, 12, 10, 9, 8, 7, 6, 5, 4, 3, or 2 mutations) relative to a binding protein described herein, e.g., mutations which do not have a substantial effect on protein 25 function. The mutations can be present in framework regions, CDRs, and/or constant regions. In some embodiments, the mutations are present in a framework region. In some embodiments, the mutations are present in a CDR. In some embodiments, the mutations are present in a constant region. Whether or not a particular substitution will be tolerated, i.e., will not adversely affect biological properties, such as binding activity 30 can be predicted, e.g., by evaluating whether the mutation is conservative or by the method of Bowie, et al. (1990) Science 247:1306-1310. 22/151 An "effectively human" immunoglobulin variable region is an immunoglobulin variable region that includes a sufficient number of human framework amino acid positions such that the immunoglobulin variable region does not elicit an immunogenic response in a normal human. An "effectively human" antibody is an antibody that 5 includes a sufficient number of human amino acid positions such that the antibody does not elicit an immunogenic response in a normal human. An "epitope" refers to the site on a target compound that is bound by a binding protein (e.g., an antibody such as a Fab or full length antibody). In the case where the target compound is a protein, the site can be entirely composed of amino acid 10 components, entirely composed of chemical modifications of amino acids of the protein (e.g., glycosyl moieties), or composed of combinations thereof. Overlapping epitopes include at least one common amino acid residue, glycosyl group, phosphate group, sulfate group, or other molecular feature. A first binding protein (e.g., antibody) "binds to the same epitope" as a second 15 binding protein (e.g., antibody) if the first binding protein binds to the same site on a target compound that the second binding protein binds, or binds to a site that overlaps (e.g., 50%, 60%, 70%, 80%, 90%, or 100% overlap, e.g., in terms of amino acid sequence or other molecular feature (e.g., glycosyl group, phosphate group, or sulfate group)) with the site that the second binding protein binds. 20 A first binding protein (e.g., antibody) "competes for binding" with a second binding protein (e.g., antibody) if the binding of the first binding protein to its epitope decreases (e.g., by 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, 100%, or more) the amount of the second binding protein that binds to its epitope. The competition can be direct (e.g., the first binding protein binds to an epitope that is the same as, or overlaps 25 with, the epitope bound by the second binding protein), or indirect (e.g., the binding of the first binding protein to its epitope causes a steric change in the target compound that decreases the ability of the second binding protein to bind to its epitope). Calculations of "homology" or "sequence identity" between two sequences (the terms are used interchangeably herein) are performed as follows. The sequences are 30 aligned for optimal comparison purposes (e.g., gaps can be introduced in one or both of a first and a second amino acid or nucleic acid sequence for optimal alignment and non 23/151 homologous sequences can be disregarded for comparison purposes). The optimal alignment is determined as the best score using the GAP program in the GCG software package with a Blossum 62 scoring matrix with a gap penalty of 12, a gap extend penalty of 4, and a frameshift gap penalty of 5. The amino acid residues or nucleotides at 5 corresponding amino acid positions or nucleotide positions are then compared. When a position in the first sequence is occupied by the same amino acid residue or nucleotide as the corresponding position in the second sequence, then the molecules are identical at that position (as used herein amino acid or nucleic acid "identity" is equivalent to amino acid or nucleic acid "homology"). The percent identity between the two sequences is a 10 function of the number of identical positions shared by the sequences. In a preferred embodiment, the length of a reference sequence aligned for comparison purposes is at least 30%, preferably at least 40%, more preferably at least 50%, even more preferably at least 60%, and even more preferably at least 70%, 80%, 90%, 92%, 95%, 97%, 98%, or 100% of the length of the reference sequence. For 15 example, the reference sequence may be the length of the immunoglobulin variable domain sequence. A "humanized" immunoglobulin variable region is an immunoglobulin variable region that is modified to include a sufficient number of human framework amino acid positions such that the immunoglobulin variable region does not elicit an immunogenic 20 response in a normal human. Descriptions of "humanized" immunoglobulins include, for example, U.S. 6,407,213 and U.S. 5,693,762. As used herein, the term "hybridizes under low stringency, medium stringency, high stringency, or very high stringency conditions" describes conditions for hybridization and washing. Guidance for performing hybridization reactions can be 25 found in Current Protocols in Molecular Biology, John Wiley & Sons, N.Y. (1989), 6.3.1 6.3.6. Aqueous and nonaqueous methods are described in that reference and either can be used. Specific hybridization conditions referred to herein are as follows: (1) low stringency hybridization conditions in 6X sodium chloride/sodium citrate (SSC) at about 45'C, followed by two washes in 0.2X SSC, 0.1% SDS at least at 50'C (the temperature 30 of the washes can be increased to 55'C for low stringency conditions); (2) medium stringency hybridization conditions in 6X SSC at about 45'C, followed by one or more 24/151 washes in 0.2X SSC, 0.1% SDS at 60'C; (3) high stringency hybridization conditions in 6X SSC at about 45'C, followed by one or more washes in 0.2X SSC, 0.1% SDS at 65'C; and (4) very high stringency hybridization conditions are 0.5M sodium phosphate, 7% SDS at 65'C, followed by one or more washes at 0.2X SSC, 1% SDS at 65'C. Very 5 high stringency conditions (4) are the preferred conditions and the ones that should be used unless otherwise specified. The disclosure includes nucleic acids that hybridize with low, medium, high, or very high stringency to a nucleic acid described herein or to a complement thereof, e.g., nucleic acids encoding a binding protein described herein. The nucleic acids can be the same length or within 30, 20, or 10% of the length of the 10 reference nucleic acid. The nucleic acid can correspond to a region encoding an immunoglobulin variable domain sequence described herein. An "isolated composition" refers to a composition that is removed from at least 90% of at least one component of a natural sample from which the isolated composition can be obtained. Compositions produced artificially or naturally can be "compositions of 15 at least" a certain degree of purity if the species or population of species of interests is at least 5, 10, 25, 50, 75, 80, 90, 92, 95, 98, or 99% pure on a weight-weight basis. An "isolated" protein refers to a protein that is removed from at least 90% of at least one component of a natural sample from which the isolated protein can be obtained. Proteins can be "of at least" a certain degree of purity if the species or population of 20 species of interest is at least 5, 10, 25, 50, 75, 80, 90, 92, 95, 98, or 99% pure on a weight-weight basis. The term "mucositis" refers to inflammation of any of the mucous membranes lining the digestive tract from the mouth on down to the anus. Mucositis is a common side effect of chemotherapy and of radiotherapy that involves any part of the digestive 25 tract. "Oral mucositis" refers to mucositis that affects the mucous membranes lining the mouth. "Esophageal mucositis" refers to mucositis that affects the mucous membranes of the esophagus, whereas "pharyngeal mucositis" refers to mucositis that affects the mucous membranes of the pharynx. "Gastrointestinal mucositis" refers to mucositis that affects the mucous membranes of the gastrointestinal tract. 30 A "non-essential" amino acid residue is a residue that can be altered from the wild-type sequence of the binding agent, e.g., the antibody, without abolishing or more 25/151 preferably, without substantially altering a biological activity, whereas changing an ''essential" amino acid residue results in a substantial loss of activity. A "patient", "subject" or "host" (these terms are used interchangeably) to be treated by the subject method may mean either a human or non-human animal. 5 The term "kallikrein" (e.g., tissue and plasma kallikrein) refers to peptidases (enzymes that cleave peptide bonds in proteins), a subgroup of the serine protease family. There are 15 known tissue kallikreins (KLK1, KLK2, KLK3, KLK4, KLK5, KLK6, KLK7, KLK8, KLK9, KLK1O, KLK11, KLK12, KLK13, KLK14 and KLK15) and a single plasma kallikrein (KLKb1). Both plasma kallikrein and tissue kallikrein 1 (KLK1) 10 cleave kininogen to generate kinins, potent pro-inflammatory peptides. DX-88 (also referred to herein as "PEP-1")is a potent (Ki < 1 nM) and specific inhibitor of plasma kallikrein (NP_000883). (See also e.g., WO 95/21601 or WO 2003/103475). The amino acid sequence of KLKb1 (plasma kallikrein) is: 15 KLKbl >gil78191798IrefINP_000883.21 plasma kallikrein B1 precursor [Homo sapiens] MILFKQATYFISLFATVSCGCLTQLYENAFFRGGDVASMYTPNAQYCQMRCTFHPRCLLFSFLPA SSINDMEKRFGCFLKDSVTGTLPKVHRTGAVSGHSLKQCGHQISACHRDIYKGVDMRGVNFNVSKVSSVEE 20 CQKRCTSNIRCQFFSYATQTFHKAEYRNNCLLKYSPGGTPTAIKVLSNVESGFSLKPCALSEIGCHMNIFQ HLAFSDVDVARVLTPDAFVCRTICTYHPNCLFFTFYTNVWKIESQRNVCLLKTSESGTPSSSTPQENTISG YSLLTCKRTLPEPCHSKIYPGVDFGGEELNVTFVKGVNVCQETCTKMIRCQFFTYSLLPEDCKEEKCKCFL RLSMDGSPTRIAYGTQGSSGYSLRLCNTGDNSVCTTKTSTRIVGGTNSSWGEWPWQVSLQVKLTAQRHLCG GSLIGHQWVLTAAHCFDGLPLQDVWRIYSGILNLSDITKDTPFSQIKEIIIHQNYKVSEGNHDIALIKLQA 25 PLNYTEFQKPICLPSKGDTSTIYTNCWVTGWGFSKEKGEIQNILQKVNIPLVTNEECQKRYQDYKITQRMV CAGYKEGGKDACKGDSGGPLVCKHNGMWRLVGITSWGEGCARREQPGVYTKVAEYMDWILEKTQSSDGKAQ MQSPA DX-2300 and related antibodies are potent and specific inhibitors of tissue kallikrein 1 (AAH05313. 1). DX-2300 (also referred to as "M0131-F07") is described in 30 U.S. Patent No.: 7,329,737. KLK1 >gil3529059|gblAAH05313.l Kallikrein 1 [Homo sapiens] MWFLVLCLALSLGGTGAAPPIQSRIVGGWECEQHSQPWQAALYHFSTFQCGGILVHRQWVLTAAHCISDN 35 YQLWLGRHNLFDDENTAQFVHVSESFPHPGFNMSLLENHTRQADEDYSHDLMLLRLTEPADTITDAVKVV ELPTQEPEVGSTCLASGWGSIEPENFSFPDDLQCVDLKILPNDECKKVHVQKVTDFMLCVGHLEGGKDTC 26/151 VGDSGGPLMCDGVLQGVTSWGYVPCGTPNKPSVAVRVLSYVKWIEDTIAENS The phrases "parenteral administration" and "administered parenterally" as used herein means modes of administration other than enteral and topical administration, 5 usually by injection, and includes, without limitation, intravenous, intramuscular, intraarterial, intrathecal, intracapsular, intraorbital, intracardiac, intradermal, intraperitoneal, transtracheal, subcutaneous, subcuticular, intraarticular, subcapsular, subarachnoid, intraspinal, epidural and intrasternal injection and infusion. The term "preventing" a disease in a subject refers to subjecting the subject to a 10 pharmaceutical treatment, e.g., the administration of a drug, such that at least one symptom of the disease is prevented, that is, administered prior to clinical manifestation of the unwanted condition (e.g., disease or other unwanted state of the host animal) so that it protects the host against developing the unwanted condition. "Preventing" a disease may also be referred to as "prophylaxis" or "prophylactic treatment." 15 A "prophylactically effective amount" refers to an amount effective, at dosages and for periods of time necessary, to achieve the desired prophylactic result. Typically, because a prophylactic dose is used in subjects prior to or at an earlier stage of disease, the prophylactically effective amount is likely but not necessarily less than the therapeutically effective amount. 20 As used herein, the term "substantially identical" (or "substantially homologous") is used herein to refer to a first amino acid or nucleic acid sequence that contains a sufficient number of identical or equivalent (e.g., with a similar side chain, e.g., conserved amino acid substitutions) amino acid residues or nucleotides to a second amino acid or nucleic acid sequence such that the first and second amino acid or nucleic acid 25 sequences have (or encode proteins having) similar activities, e.g., a binding activity, a binding preference, or a biological activity. In the case of antibodies, the second antibody has the same specificity and has at least 50%, at least 25%, or at least 10% of the affinity relative to the same antigen. Sequences similar or homologous (e.g., at least about 85% sequence identity) to 30 the sequences disclosed herein are also part of this application. In some embodiments, the sequence identity can be about 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or higher. In some embodiments, a plasma kallikrein binding protein can have 27/151 about 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or higher sequence identity to a binding protein described herein. In some embodiments, a plasma kallikrein binding protein can have about 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or higher sequence identity in the HC and/or LC framework regions (e.g., HC and/or 5 LC FR 1, 2, 3, and/or 4) to a binding protein described herein. In some embodiments, a plasma kallikrein binding protein can have about 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or higher sequence identity in the HC and/or LC CDRs (e.g., HC and/or LC CDR1, 2, and/or 3) to a binding protein described herein. In some embodiments, a plasma kallikrein binding protein can have about 85%, 90%, 91%, 92%, 10 93%, 94%, 95%, 96%, 97%, 98%, 99% or higher sequence identity in the constant region (e.g., CHI, CH2, CH3, and/or CLI) to a binding protein described herein. In addition, substantial identity exists when the nucleic acid segments hybridize under selective hybridization conditions (e.g., highly stringent hybridization conditions), to the complement of the strand. The nucleic acids may be present in whole cells, in a 15 cell lysate, or in a partially purified or substantially pure form. Motif sequences for biopolymers can include positions which can be varied amino acids. For example, the symbol "X" in such a context generally refers to any amino acid (e.g., any of the twenty natural amino acids) unless otherwise specified, e.g., to refer to any non-cysteine amino acid. Other allowed amino acids can also be indicated for 20 example, using parentheses and slashes. For example, "(A/W/F/N/Q)" means that alanine, tryptophan, phenylalanine, asparagine, and glutamine are allowed at that particular position. Statistical significance can be determined by any art known method. Exemplary statistical tests include: the Students T-test, Mann Whitney U non-parametric test, and 25 Wilcoxon non-parametric statistical test. Some statistically significant relationships have a P value of less than 0.05 or 0.02. Particular binding proteins may show a difference, e.g., in specificity or binding, that are statistically significant (e.g., P value < 0.05 or 0.02). The terms "induce", "inhibit", "potentiate", "elevate", "increase", "decrease" or the like, e.g., which denote distinguishable qualitative or quantitative differences between 30 two states, and may refer to a difference, e.g., a statistically significant difference, between the two states. 28/151 A "therapeutically effective amount" refers to an amount effective, at dosages and for periods of time necessary, to achieve the desired therapeutic result. A therapeutically effective amount of the composition may vary according to factors such as the disease state, age, sex, and weight of the individual, and the ability of the protein to elicit a 5 desired response in the individual. A therapeutically effective amount is also one in which any toxic or detrimental effects of the composition is outweighed by the therapeutically beneficial effects. A "therapeutically effective dosage" preferably modulates a measurable parameter, e.g., the degree of mucositis as evaluated visually by a statistically significant 10 degree. For example, a therapeutically effective dosage can reduce the degree of a symptom of mucositis by at least about 20%, more preferably by at least about 40%, even more preferably by at least about 60%, and still more preferably by at least about 80% as compared to the symptom prior to treatment. The ability of a compound to modulate a measurable parameter, e.g., a disease-associated parameter, can be evaluated in an animal 15 model system predictive of efficacy in human disorders and conditions, e.g., e.g., oral mucositis in a hamster or rodent model. Alternatively, this property of a composition can be evaluated by examining the ability of the compound to modulate a parameter in vitro. "Treating" mucositis in a subject or "treating" a subject having mucositis refers to subjecting the subject to a pharmaceutical treatment, e.g., the administration of a drug, 20 such that at least one symptom of the disease is cured, alleviated or decreased. "Treating" mucositis may be evaluated by any one of the following parameters: - Reduction in the frequency of development of mucositis (or) - Reduction in the duration of mucositis at any given level of disease severity (or) 25 - Reduction in the severity (grades 1-4) of development of mucositis at any time course during treatment (or) - Reduction in any of the associated signs or symptoms of mucositis, including but not limited to: o Pain 30 o Edema o Erythema 29/151 o Secondary bacterial colonization o Limitation of food consumption (solid, liquid) o Fatigue o Ability to tolerate higher or repeat doses of chemotherapy or radiation 5 therapy in the aggregate treated population compared to aggregate non treated patient populations Kallikrein Inhibitors Kunitz Domain Inhibitors. A number of useful inhibitors of kallikrein, either 10 tissue and/or plasma kallikrein, include a Kunitz domain. As used herein, a "Kunitz domain" is a polypeptide domain having at least 51 amino acids and containing at least two, and preferably three, disulfides. The domain is folded such that the first and sixth cysteines, the second and fourth, and the third and fifth cysteines form disulfide bonds (e.g., in a Kunitz domain having 58 amino acids, cysteines 15 can be present at positions corresponding to amino acids 5, 14, 30, 38, 51, and 55, according to the number of the BPTI homologous sequences provided below, and disulfides can form between the cysteines at position 5 and 55, 14 and 38, and 30 and 51), or, if two disulfides are present, they can form between a corresponding subset of cysteines thereof. The spacing between respective cysteines can be within 7, 5, 4, 3, 2, 1 20 or 0 amino acids of the following spacing between positions corresponding to: 5 to 55, 14 to 38, and 30 to 51, according to the numbering of the BPTI sequence provided below. The BPTI sequence can be used as a reference to refer to specific positions in any generic Kunitz domain. Comparison of a Kunitz domain of interest to BPTI can be performed by identifying the best fit alignment in which the number of aligned cysteines in maximized. 25 The 3D structure (at high resolution) of the Kunitz domain of BPTI is known. One of the X-ray structures is deposited in the Brookhaven Protein Data Bank as "6PTI". The 3D structure of some BPTI homologues (Eigenbrot et al., (1990) Protein Engineering, 3(7):591-598; Hynes et al., (1990) Biochemistry, 29:10018-10022) are known. At least eighty one Kunitz domain sequences are known. Known human 30 homologues include three Kunitz domains of LACI (Wun et al., (1988) J. Biol. Chem. 30/151 263(13):6001-6004; Girard et al., (1989) Nature, 338:518-20; Novotny et al, (1989) J. Biol. Chem., 264(31):18832-18837) two Kunitz domains of Inter-a-Trypsin Inhibitor, APP-I (Kido et al., (1988) J. Biol. Chem., 263(34):18104-18107), a Kunitz domain from collagen, three Kunitz domains of TFPI-2 (Sprecher et al., (1994) PNAS USA, 91:3353 5 3357), the Kunitz domains of hepatocyte growth factor activator inhibitor type 1, the Kunitz domains of Hepatocyte growth factor activator inhibitor type 2, the Kunitz domains described in U.S. Patent Publication No.: 2004-0152633. LACI is a human serum phosphoglycoprotein with a molecular weight of 39 kDa (amino acid sequence in Table 1) containing three Kunitz domains. 10 Table 1: Exemplary Natural Kunitz Domains LACI: (SEQ ID 1 MIYTMKKVHA LWASVCLLLN LAPAPLNAds eedeehtiit dtelpplklM NO. 54) 51 HSFCAFKADD GPCKAIMKRF FFNIFTRQCE EFIYGGCEGN QNRFESLEEC 101 KKMCTRDnan riikttlqqe kpdfCfleed pgiCrgyitr yfynnqtkqC 151 erfkyggClg nmnnfetlee CkniCedgpn gfqvdnygtq lnavnnsltp 201 qstkvpslfe fhgpswCltp adrglCrane nrfyynsvig kCrpfkysgC 251 ggnennftsk qeClraCkkg fiqriskggl iktkrkrkkq rvkiayeeif 301 vknm The signal sequence (1-28) is uppercase and underscored LACI-K1 (50-107) is uppercase LACI-K2 (121-178) is underscored LACI-K3 (211-270) is bold BPTI 1 2 3 4 5 (SEQ ID 1234567890123456789012345678901234567890123456789012345678 NO:55) RPDFCLEPPYTGPCKARIIRYFYNAKAGLCQTFVYGGCRAKRNNFKSAEDCMRTCGGA The Kunitz domains above are referred to as LACI-KI (residues 50 to 107), LACI-K2 (residues 121 to 178), and LACI-K3 (213 to 270). The cDNA sequence of LACI is reported in Wun et al. (J. Biol. Chem., 1988, 263(13):6001-6004). Girard et al. 15 (Nature, 1989, 338:518-20) reports mutational studies in which the P1 residues of each of the three Kunitz domains were altered. LACI-KI inhibits Factor VIIa (F.VIIa) when EVIla is complexed to tissue factor and LACI-K2 inhibits Factor Xa. Proteins containing exemplary Kunitz domains include the following, with SWISS-PROT Accession Numbers in parentheses: 20 A4_HUMAN (P05067), A4_MACFA (P53601), A4_MACMU (P29216), A4_MOUSE (P12023), A4_RAT (P08592), A4_SAISC (Q95241), AMBPPLEPL (P36992), APP2_HUMAN (Q06481), APP2_RAT (P15943), AXPlANTAF (P81547), AXP2_ANTAF (P81548), BPT1_BOVIN (P00974), BPT2_BOVIN (P04815), CA17_HUMAN (Q02388), CA36_CHICK (P15989), 31/151 CA36_HUMAN (P12111), CRPTBOOMI (P81162), ELAC_MACEU (062845), ELACTRIVU (Q29143), EPPIHUMAN (095925), EPPIMOUSE (Q9DA01), HTIB_MANSE (P26227), IBPCARCR (P00993), IBPCBOVIN (P00976), IBPITACTR (P16044), IBPSBOVIN (P00975), ICS3_BOMMO (P07481), 5 IMAPDROFU (P11424), IP52_ANESU (P10280), ISClBOMMO (P10831), ISC2_BOMMO (P10832), ISH1_STOHE (P31713), ISH2_STOHE (P81129), ISIKHELPO (P00994), ISP2_GALME (P81906), IVB1_BUNFA (P25660), IVB1_BUNMU (P00987), IVB1VIPAA (P00991), IVB2_BUNMU (P00989), IVB2_DABRU (P00990), IVB2_HEMHA (P00985), IVB2 _NAJNI (P00986), 10 IVB3_VIPAA (P00992), IVBBDENPO (P00983), IVBCNAJNA (P19859), IVBCOPHHA (P82966), IVBEDENPO (P00984), IVBIDENAN (P00980), IVBIDENPO (P00979), IVBKDENAN (P00982), IVBKDENPO (P00981), IVBTERIMA (P24541), IVBTNAJNA (P20229), MCPI_MELCP (P82968), SBPISARBU (P26228), SPT3_HUMAN (P49223), TKD1_BOVIN (Q28201), 15 TKD1_SHEEP (Q29428), TXCADENAN (P81658), UPTIPIG (Q29100), AMBPBOVIN (P00978), AMBPHUMAN (P02760), AMBPMERUN (Q62577), AMBPMESAU (Q60559), AMBP MOUSE (Q07456), AMBPPIG (P04366), AMBPRAT (Q64240), IATR HORSE (P04365), IATRSHEEP (P13371), SPT1_HUMAN (043278), SPT1 MOUSE (Q9RO97), SPT2_HUMAN (043291), 20 SPT2_MOUSE (Q9WU03), TFP2_HUMAN (P48307), TFP2_MOUSE (035536), TFPIHUMAN (P10646), TFPI MACMU (Q28864), TFPIMOUSE (054819), TFPI_RABIT (P19761), TFPIRAT (Q02445), YN81_CAEEL (Q03610) A variety of methods can be used to identify a Kunitz domain from a sequence 25 database. For example, a known amino acid sequence of a Kunitz domain, a consensus sequence, or a motif (e.g., the ProSite Motif) can be searched against the GenBank sequence databases (National Center for Biotechnology Information, National Institutes of Health, Bethesda MD), e.g., using BLAST; against Pfam database of HMMs (Hidden Markov Models) (e.g., using default parameters for Pfam searching; against the SMART 30 database; or against the ProDom database. For example, the Pfam Accession Number PF00014 of Pfam Release 9 provides numerous Kunitz domains and an HMM for identify Kunitz domains. A description of the Pfam database can be found in Sonhammer et al. (1997) Proteins 28(3):405-420 and a detailed description of HMMs can be found, for example, in Gribskov et al. (1990) Meth. Enzymol. 183:146-159; Gribskov et al. 35 (1987) Proc. Natl. Acad. Sci. USA 84:4355-4358; Krogh et al. (1994) J. Mol. Biol. 235:1501-1531; and Stultz et al. (1993) Protein Sci. 2:305-314. The SMART database (Simple Modular Architecture Research Tool, EMBL, Heidelberg, DE) of HMMs as described in Schultz et al. (1998), Proc. Natl. Acad. Sci. USA 95:5857 and Schultz et al. (2000) Nucl. Acids Res 28:23 1. The SMART database contains domains identified by 40 profiling with the hidden Markov models of the HMMer2 search program (R. Durbin et al. (1998) Biological sequence analysis: probabilistic models of proteins and nucleic 32/151 acids. Cambridge University Press). The database also is annotated and monitored. The ProDom protein domain database consists of an automatic compilation of homologous domains (Corpet et al. (1999), Nucl. Acids Res. 27:263-267). Current versions of ProDom are built using recursive PSI-BLAST searches (Altschul et al. (1997) Nucleic 5 Acids Res. 25:3389-3402; Gouzy et al. (1999) Computers and Chemistry 23:333-340.) of the SWISS-PROT 38 and TREMBL protein databases. The database automatically generates a consensus sequence for each domain. Prosite lists the Kunitz domain as a motif and identifies proteins that include a Kunitz domain. See, e.g., Falquet et al. Nucleic Acids Res. 30:235-238(2002). 10 Kunitz domains interact with target protease using, primarily, amino acids in two loop regions ("binding loops"). The first loop region is between about residues corresponding to amino acids 13-20 of BPTI. The second loop region is between about residues corresponding to amino acids 31-39 of BPTI. An exemplary library of Kunitz domains varies one or more amino acid positions in the first and/or second loop regions. 15 Particularly useful positions to vary, when screening for Kunitz domains that interact with kallikrein or when selecting for improved affinity variants, include: positions 13, 15, 16, 17, 18, 19, 31, 32, 34, and 39 with respect to the sequence of BPTI. At least some of these positions are expected to be in close contact with the target protease. It is also useful to vary other positions, e.g., positions that are adjacent to the aforementioned 20 positions in the three-dimensional structure. The "framework region" of a Kunitz domain is defined as those residues that are a part of the Kunitz domain, but specifically excluding residues in the first and second binding loops regions, i.e., about residues corresponding to amino acids 13-20 of BPTI and 31-39 of BPTI. Conversely, residues that are not in the binding loop may tolerate a 25 wider range of amino acid substitution (e.g., conservative and/or non-conservative substitutions). In one embodiment, these Kunitz domains are variant forms of the looped structure including Kunitz domain 1 of human lipoprotein-associated coagulation inhibitor (LACI) protein. LACI contains three internal, well-defined, peptide loop 30 structures that are paradigm Kunitz domains (Girard, T. et al., 1989. Nature, 338:518 520). Variants of Kunitz domain 1 of LACI described herein have been screened, 33/151 isolated and bind kallikrein with enhanced affinity and specificity (see, for example, U.S. Pat. Nos. 5,795,865 and 6,057,287). These methods can also be applied to other Kunitz domain frameworks to obtain other Kunitz domains that interact with kallikrein, e.g., plasma kallikrein. Useful modulators of kallikrein function typically bind and/or inhibit 5 kallikrein, as determined using kallikrein binding and inhibition assays. An exemplary polypeptide that includes a Kunitz domain that inhibits plasma kallikrein has or includes the amino acid sequence defined by amino acids 3-60 of SEQ ID NO:2. Another exemplary polypeptide that includes a Kunitz domain that inhibits plasma kallikrein has or includes the amino acid sequence of SEQ ID NO:2. 10 An exemplary polypeptide includes the amino acid sequence: Xaal Xaa2 Xaa3 Xaa4 Cys Xaa6 Xaa7 Xaa8 Xaa9 Xaa10 Xaall Gly Xaa13 Cys Xaa15 Xaa16 Xaa17 Xaa18 Xaa19 Xaa20 Xaa21 Xaa22 Xaa23 Xaa24 Xaa25 Xaa26 Xaa27 Xaa28 Xaa29 Cys Xaa31 Xaa32 Phe Xaa34 Xaa35 Gly Gly Cys Xaa39 Xaa40 Xaa41 Xaa42 Xaa43 Xaa44 Xaa45 Xaa46 Xaa47 Xaa48 Xaa49 Xaa50 Cys Xaa52 Xaa53 15 Xaa54 Cys Xaa56 Xaa57 Xaa58 (SEQ ID NO:1). "Xaa" refers to a position in a peptide chain that can be any of a number of different amino acids. In a first example, Xaa can by any amino acid except cysteine. In another example, one or more of the following apply: Xaa10 can be Asp or Glu; Xaa 11 can be Asp, Gly, Ser, Val, Asn, Ile, Ala or Thr; Xaa13 can be Pro, Arg, His, Asn, Ser, 20 Thr, Ala, Gly, Lys or Gln; Xaa15 can be Arg, Lys, Ala, Ser, Gly, Met, Asn or Gln; Xaa16 can be Ala, Gly, Ser, Asp or Asn; Xaa17 can be Ala, Asn, Ser, Ile, Gly, Val, Gln or Thr; Xaal8 can be His, Leu, Gln or Ala; Xaa19 can be Pro, Gln, Leu, Asn or Ile; Xaa21 can be Trp, Phe, Tyr, His or Ile; Xaa31 can be Glu, Asp, Gln, Asn, Ser, Ala, Val, Leu, Ile or Thr; Xaa32 can be Glu, Gln, Asp Asn, Pro, Thr, Leu, Ser, Ala, Gly or Val; Xaa34 can be 25 Ile, Thr, Ser, Val, Ala, Asn, Gly or Leu; Xaa35 can be Tyr, Trp or Phe; Xaa39 can be Glu, Gly, Ala, Ser or Asp. Amino acids Xaa6, Xaa7, Xaa8, Xaa9, Xaa20, Xaa24, Xaa25, Xaa26, Xaa27, Xaa28, Xaa29, Xaa4l, Xaa42, Xaa44, Xaa46, Xaa47, Xaa48, Xaa49, Xaa50, Xaa52, Xaa53 and Xaa54 can be any amino acid. Additionally, each of the first four (Xaal, Xaa2, Xaa3, Xaa4) and at last three 9 30 Xaa56, Xaa57 or Xaa58) amino acids of SEQ ID NO: 1 can optionally be present or absent and can be any amino acid, if present, e.g., any non-cysteine amino acid 34/151 In one embodiment, the polypeptide has a sequence with one or more of the following properties: Xaal 1 can be Asp, Gly, Ser or Val; Xaa13 can be Pro, Arg, His or Asn; Xaa15 can be Arg or Lys; Xaa16 can be Ala or Gly; Xaa17 can be Ala, Asn, Ser or Ile; Xaa18 can be His, Leu or Gln; Xaa19 can be Pro, Gln or Leu; Xaa21 can be Trp or 5 Phe; Xaa31 is Glu; Xaa32 can be Glu or Gln; Xaa34 can be Ile, Thr or Ser; Xaa35 is Tyr; and Xaa39 can be Glu, Gly or Ala. An exemplary polypeptide can include the following amino acids: Xaa10 is Asp; Xaall is Asp; Xaa13 can be Pro or Arg; Xaa15 is Arg; Xaa16 can be Ala or Gly; Xaa17 is Ala; Xaa18 is His; Xaa19 is Pro; Xaa21 is Trp; Xaa31 is Glu; Xaa32 is Glu; Xaa34 can 10 be Ile or Ser; Xaa35 is Tyr; and Xaa39 is Gly. It is also possible to use portions of the polypeptides described herein. For example, polypeptides could include binding domains for specific kallikrein epitopes. For example, the binding loops of Kunitz domains can by cyclized and used in isolation or can be grafted onto another domain, e.g., a framework of another Kunitz domain. It is 15 also possible to remove one, two, three, or four amino acids from the N-terminus of an amino acid sequence described herein, and/or one, two, three, four, or five amino acids from the C-terminus of an amino acid sequence described herein. Examples of sequences encompassed by SEQ ID NO: 1 as follows (where not indicated, "Xaa" refers to any non-cysteine amino acid): 20 Met His Ser Phe Cys Ala Phe Lys Ala Xaa10 Xaall Gly Xaal3 Cys Xaal5 Xaa16 Xaa17 Xaa18 Xaa19 Arg Xaa21 Phe Phe Asn Ile Phe Thr Arg Gln Cys Xaa31 Xaa32 Phe Xaa34 Xaa35 Gly Gly Cys Xaa39 Gly Asn Gln Asn Arg Phe Glu Ser Leu Glu Glu Cys Lys Lys Met Cys Thr Arg Asp (SEQ ID NO:33), 25 Met His Ser Phe Cys Ala Phe Lys Ala Asp Asp Gly Pro Cys Arg Ala Ala His Pro Arg Trp Phe Phe Asn Ile Phe Thr Arg Gln Cys Glu Glu Phe Ile Tyr Gly Gly Cys Glu Gly Asn Gln Asn Arg Phe Glu Ser Leu Glu Glu Cys Lys Lys Met Cys Thr Arg Asp (amino acids 3-60 of SEQ ID NO:2), 30 Met His Ser Phe Cys Ala Phe Lys Ala Asp Asp Gly Pro Cys Lys Ala Asn His Leu Arg Phe Phe Phe Asn Ile Phe Thr Arg Gln Cys Glu Glu Phe Ser Tyr Gly Gly Cys Gly 35/151 Gly Asn Gln Asn Arg Phe Glu Ser Leu Glu Glu Cys Lys Lys Met Cys Thr Arg Asp (SEQ ID NO:4), Met His Ser Phe Cys Ala Phe Lys Ala Asp Asp Gly His Cys Lys Ala Asn His Gln 5 Arg Phe Phe Phe Asn Ile Phe Thr Arg Gln Cys Glu Glu Phe Thr Tyr Gly Gly Cys Gly Gly Asn Gln Asn Arg Phe Glu Ser Leu Glu Glu Cys Lys Lys Met Cys Thr Arg Asp (SEQ ID NO:5), Met His Ser Phe Cys Ala Phe Lys Ala Asp Asp Gly His Cys Lys Ala Asn His Gln 10 Arg Phe Phe Phe Asn Ile Phe Thr Arg Gln Cys Glu Gln Phe Thr Tyr Gly Gly Cys Ala Gly Asn Gln Asn Arg Phe Glu Ser Leu Glu Glu Cys Lys Lys Met Cys Thr Arg Asp (SEQ ID NO:6), Met His Ser Phe Cys Ala Phe Lys Ala Asp Asp Gly His Cys Lys Ala Ser Leu Pro 15 Arg Phe Phe Phe Asn Ile Phe Thr Arg Gln Cys Glu Glu Phe Ile Tyr Gly Gly Cys Gly Gly Asn Gln Asn Arg Phe Glu Ser Leu Glu Glu Cys Lys Lys Met Cys Thr Arg Asp (SEQ ID NO:7), Met His Ser Phe Cys Ala Phe Lys Ala Asp Asp Gly His Cys Lys Ala Asn His Gln 20 Arg Phe Phe Phe Asn Ile Phe Thr Arg Gln Cys Glu Glu Phe Ser Tyr Gly Gly Cys Gly Gly Asn Gln Asn Arg Phe Glu Ser Leu Glu Glu Cys Lys Lys Met Cys Thr Arg Asp (SEQ ID NO:8), Met His Ser Phe Cys Ala Phe Lys Ala Asp Asp Gly His Cys Lys Gly Ala His Leu 25 Arg Phe Phe Phe Asn Ile Phe Thr Arg Gln Cys Glu Glu Phe Ile Tyr Gly Gly Cys Glu Gly Asn Gln Asn Arg Phe Glu Ser Leu Glu Glu Cys Lys Lys Met Cys Thr Arg Asp (SEQ ID NO:9), Met His Ser Phe Cys Ala Phe Lys Ala Asp Asp Gly Arg Cys Lys Gly Ala His Leu 30 Arg Phe Phe Phe Asn Ile Phe Thr Arg Gln Cys Glu Glu Phe Ile Tyr Gly Gly Cys Glu Gly Asn Gln Asn Arg Phe Glu Ser Leu Glu Glu Cys Lys Lys Met Cys Thr Arg Asp (SEQ ID 36/151 NO:10), Met His Ser Phe Cys Ala Phe Lys Ala Asp Gly Gly Arg Cys Arg Gly Ala His Pro Arg Trp Phe Phe Asn Ile Phe Thr Arg Gln Cys Glu Glu Phe Ser Tyr Gly Gly Cys Gly 5 Gly Asn Gln Asn Arg Phe Glu Ser Leu Glu Glu Cys Lys Lys Met Cys Thr Arg Asp (SEQ ID NO:11), Met His Ser Phe Cys Ala Phe Lys Ala Asp Asp Gly Pro Cys Arg Ala Ala His Pro Arg Trp Phe Phe Asn Ile Phe Thr Arg Gln Cys Glu Glu Phe Ser Tyr Gly Gly Cys Gly 10 Gly Asn Gln Asn Arg Phe Glu Ser Leu Glu Glu Cys Lys Lys Met Cys Thr Arg Asp (SEQ ID NO:12), Met His Ser Phe Cys Ala Phe Lys Ala Asp Val Gly Arg Cys Arg Gly Ala His Pro Arg Trp Phe Phe Asn Ile Phe Thr Arg Gln Cys Glu Glu Phe Ser Tyr Gly Gly Cys Gly 15 Gly Asn Gln Asn Arg Phe Glu Ser Leu Glu Glu Cys Lys Lys Met Cys Thr Arg Asp (SEQ ID NO:13), Met His Ser Phe Cys Ala Phe Lys Ala Asp Val Gly Arg Cys Arg Gly Ala Gln Pro Arg Phe Phe Phe Asn Ile Phe Thr Arg Gln Cys Glu Glu Phe Ser Tyr Gly Gly Cys Gly 20 Gly Asn Gln Asn Arg Phe Glu Ser Leu Glu Glu Cys Lys Lys Met Cys Thr Arg Asp (SEQ ID NO: 14), Met His Ser Phe Cys Ala Phe Lys Ala Asp Asp Gly Ser Cys Arg Ala Ala His Leu Arg Trp Phe Phe Asn Ile Phe Thr Arg Gln Cys Glu Glu Phe Ser Tyr Gly Gly Cys Gly 25 Gly Asn Gln Asn Arg Phe Glu Ser Leu Glu Glu Cys Lys Lys Met Cys Thr Arg Asp (SEQ ID NO:15), Met His Ser Phe Cys Ala Phe Lys Ala Glu Gly Gly Ser Cys Arg Ala Ala His Gln Arg Trp Phe Phe Asn Ile Phe Thr Arg Gln Cys Glu Glu Phe Ser Tyr Gly Gly Cys Gly 30 Gly Asn Gln Asn Arg Phe Glu Ser Leu Glu Glu Cys Lys Lys Met Cys Thr Arg Asp (SEQ 37/151 ID NO:16), Met His Ser Phe Cys Ala Phe Lys Ala Asp Asp Gly Pro Cys Arg Gly Ala His Leu Arg Phe Phe Phe Asn Ile Phe Thr Arg Gln Cys Glu Glu Phe Ser Tyr Gly Gly Cys Gly 5 Gly Asn Gln Asn Arg Phe Glu Ser Leu Glu Glu Cys Lys Lys Met Cys Thr Arg Asp (SEQ ID NO:17), Met His Ser Phe Cys Ala Phe Lys Ala Asp Asp Gly His Cys Arg Gly Ala Leu Pro Arg Trp Phe Phe Asn Ile Phe Thr Arg Gln Cys Glu Glu Phe Ser Tyr Gly Gly Cys Gly 10 Gly Asn Gln Asn Arg Phe Glu Ser Leu Glu Glu Cys Lys Lys Met Cys Thr Arg Asp (SEQ ID NO:18), Met His Ser Phe Cys Ala Phe Lys Ala Asp Ser Gly Asn Cys Arg Gly Asn Leu Pro Arg Phe Phe Phe Asn Ile Phe Thr Arg Gln Cys Glu Glu Phe Ser Tyr Gly Gly Cys Gly 15 Gly Asn Gln Asn Arg Phe Glu Ser Leu Glu Glu Cys Lys Lys Met Cys Thr Arg Asp (SEQ ID NO:19), Met His Ser Phe Cys Ala Phe Lys Ala Asp Ser Gly Arg Cys Arg Gly Asn His Gln Arg Phe Phe Phe Asn Ile Phe Thr Arg Gln Cys Glu Glu Phe Ser Tyr Gly Gly Cys Gly 20 Gly Asn Gln Asn Arg Phe Glu Ser Leu Glu Glu Cys Lys Lys Met Cys Thr Arg Asp (SEQ ID NO:20), Met His Ser Phe Cys Ala Phe Lys Ala Asp Gly Gly Arg Cys Arg Ala Ile Gln Pro Arg Trp Phe Phe Asn Ile Phe Thr Arg Gln Cys Glu Glu Phe Ser Tyr Gly Gly Cys Gly 25 Gly Asn Gln Asn Arg Phe Glu Ser Leu Glu Glu Cys Lys Lys Met Cys Thr Arg Asp (SEQ ID NO:21), Met His Ser Phe Cys Ala Phe Lys Ala Asp Asp Gly Arg Cys Arg Gly Ala His Pro Arg Trp Phe Phe Asn Ile Phe Thr Arg Gln Cys Glu Glu Phe Ser Tyr Gly Gly Cys Gly 30 Gly Asn Gln Asn Arg Phe Glu Ser Leu Glu Glu Cys Lys Lys Met Cys Thr Arg Asp (SEQ ID NO:22), 38/151 Glu Ala Met His Ser Phe Cys Ala Phe Lys Ala Asp Asp Gly Pro Cys Arg Ala Ala His Pro Arg Trp Phe Phe Asn Ile Phe Thr Arg Gln Cys Glu Glu Phe Ile Tyr Gly Gly Cys Glu Gly Asn Gln Asn Arg Phe Glu Ser Leu Glu Glu Cys Lys Lys Met Cys Thr Arg Asp 5 (SEQ ID NO:2). Additional examples of sequence include those that differ by at least one amino acid, but fewer than seven, six, five, four, three, or two amino acids differences relative to an amino acid sequence described herein, e.g., an amino acid sequence provided above. 10 In one embodiment, fewer than three, two, or one differences are in one of the binding loops. For example, the first binding loop may have no differences relative to an amino acid sequence described herein, e.g., an amino acid sequence provided above. In another example, neither the first nor the second binding loop differs from an amino acid sequence described herein, e.g., an amino acid sequence provided above. 15 FIGURES 2A and 2B provide an amino acid sequence alignment of these sequences, the native LACI sequence from which these variants were derived (SEQ ID NO:32), and other known Kunitz domains (SEQ ID NOS: 29-31 and 33-53). Still others polypeptides that inhibit plasma kallikrein include an about 58-amino acid sequence of amino acids 3-60 of SEQ ID NO:2 or the PEP-i polypeptide having the 60-amino acid 20 sequence of SEQ ID NO:2. The terms "PEP-i" and "DX-88" as used herein both refer to the 60-amino acid sequence of SEQ ID NO:2. A nucleotide sequence encoding the amino acid sequence of SEQ ID NO:2 is provided in SEQ ID NO:3 (see, e.g., nucleotides 309-488 in FIGURE 1). It is understood that based on the known genetic code, degenerate forms of the nucleotide sequence of SEQ ID NO:3 can be obtained by simply 25 substituting one or more of the known degenerate codons for each amino acid encoded by the nucleotide sequence. Nucleotides 7-180 of SEQ ID NO:3, and degenerate forms thereof, encode the non-naturally occurring Kunitz domain polypeptide that includes the 58-amino acid sequence of amino acids 3-60 of SEQ ID NO:2, a related sequence, or a functional fragment thereof. 30 In one embodiment, the polypeptide is other than aprotinin, e.g., differs from aprotinin, by at least one, two, three, five, ten, or fifteen amino acids. 39/151 Polypeptides described herein can be made synthetically using any standard polypeptide synthesis protocol and equipment. For example, the stepwise synthesis of a polypeptide can be carried out by the removal of an amino (N) terminal-protecting group from an initial (i.e., carboxy-terminal) amino acid, and coupling thereto of the carboxyl 5 end of the next amino acid in the sequence of the polypeptide. This amino acid is also suitably protected. The carboxyl group of the incoming amino acid can be activated to react with the N-terminus of the bound amino acid by formation into a reactive group such as formation into a carbodiimide, a symmetric acid anhydride, or an "active ester" group such as hydroxybenzotriazole or pentafluorophenyl esters. Preferred solid-phase 10 peptide synthesis methods include the BOC method, which utilizes tert-butyloxycarbonyl as the I-amino protecting group, and the FMOC method, which utilizes 9 fluorenylmethloxycarbonyl to protect the alpha-amino of the amino acid residues. Both methods are well known to those of skill in the art (Stewart, J. and Young, J., Solid-Phase Peptide Synthesis (W. H. Freeman Co., San Francisco 1989); Merrifield, J., 1963. Am. 15 Chem. Soc., 85:2149-2154; Bodanszky, M. and Bodanszky, A., The Practice of Peptide Synthesis (Springer-Verlag, New York 1984)). If desired, additional amino- and/or carboxy-terminal amino acids can be designed into the amino acid sequence and added during polypeptide synthesis. Polypeptides can also be produced using recombinant technology. Recombinant 20 methods can employ any of a number of cells and corresponding expression vectors, including but not limited to bacterial expression vectors, yeast expression vectors, baculovirus expression vectors, mammalian viral expression vectors, and the like. A polypeptide described herein can be produced by a transgenic animal, e.g., in the mammary gland of a transgenic animal. In some cases, it could be necessary or 25 advantageous to fuse the coding sequence for a polypeptide that inhibits kallikrein (e.g., a polypeptide that includes a Kunitz domain) to another coding sequence in an expression vector to form a fusion polypeptide that is readily expressed in a host cell. Part or all of the additional sequence can be removed, e.g., by protease digestion. An exemplary recombinant expression system for producing a polypeptide that 30 inhibits kallikrein (e.g., a polypeptide that includes a Kunitz domain) is a yeast expression vector, which permits a nucleic acid sequence encoding the amino acid 40/151 sequence for the inhibitor polypeptide to be linked in the same reading frame with a nucleotide sequence encoding the MATa prepro leader peptide sequence of Saccharomyces cerevisiae, which in turn is under the control of an operable yeast promoter. The resulting recombinant yeast expression plasmid can be transformed by 5 standard methods into the cells of an appropriate, compatible yeast host, which cells are able to express the recombinant protein from the recombinant yeast expression vector. Preferably, a host yeast cell transformed with such a recombinant expression vector is also able to process the fusion protein to provide an active inhibitor polypeptide. An other exemplary yeast host for producing recombinant polypeptides is Pichia pastoris. 10 As noted above, polypeptides that inhibit kallikrein can include a Kunitz domain polypeptide described herein. Some polypeptides can include an additional flanking sequence, preferably of one to six amino acids in length, at the amino and/or carboxy terminal end, provided such additional amino acids do not significantly diminish kallikrein binding affinity or kallikrein inhibition activity so as to preclude use in the 15 methods and compositions described herein. Such additional amino acids can be deliberately added to express a polypeptide in a particular recombinant host cell or can be added to provide an additional function, e.g., to provide a linker to another molecule or to provide an affinity moiety that facilitates purification of the polypeptide. Preferably, the additional amino acid(s) do not include cysteine, which could interfere with the disulfide 20 bonds of the Kunitz domain. An exemplary Kunitz domain polypeptide includes the amino acid sequence of residues 3-60 of SEQ ID NO:2. When expressed and processed in a yeast fusion protein expression system (e.g., based on the integrating expression plasmid pHIL-D2), such a Kunitz domain polypeptide retains an additional amino terminal Glu-Ala dipeptide from 25 the fusion with the MATalpha-prepro leader peptide sequence of S. cerevisiae. When secreted from the yeast host cell, most of the leader peptide is processed from the fusion protein to yield a functional polypeptide (referred to herein as "PEP-I") having the amino acid sequence of SEQ ID NO:2 (see boxed region in FIGURE 1). A typical Kunitz domain, e.g., that includes, SEQ ID NO: 1, contains a number of 30 invariant positions, e.g., positions corresponding to position 5, 14, 30, 33, 38, 45, 51 and 55 in the BPTI numbering scheme are cysteine. The spacing between these positions 41/151 may vary to the extent allowable within the Kunitz domain fold, e.g., such that three disulfide bonds are formed. Other positions such as, for example, positions 6, 7, 8, 9, 20, 24, 25, 26, 27, 28, 29, 41, 42, 44, 46, 47, 48, 49, 50, 52, 53 and 54, or positions corresponding to those positions, can be any amino acid (including non-genetically 5 encoded occurring amino acids). In a particularly preferred embodiment, one or more amino acids correspond to that of a native sequence (e.g., SEQ ID NO:32, see FIGURES 2A and 2B). In another embodiment, at least one variable position is different from that of the native sequence. In yet another preferred embodiment, the amino acids can each be individually or collectively substituted by a conservative or non-conservative 10 amino acid substitution. Conservative amino acid substitutions replace an amino acid with another amino acid of similar chemical nature and may have no affect on protein function. Non conservative amino acid substitutions replace an amino acid with another amino acid of dissimilar chemical structure. Examples of conserved amino acid substitutions include, 15 for example, Asn->Gln, Arg->Lys and Ser->Thr. In a preferred embodiment, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20 and/or 21 of these amino acids can be independently or collectively, in any combination, selected to correspond to the corresponding position of SEQ ID NO:2. Other positions, for example, positions 10, 11, 13, 15, 16, 17, 18, 19, 21, 22, 23, 20 31, 32, 34, 35, 39, 40, 43 and 45, or positions corresponding to those positions can be any of a selected set of amino acids. For example, SEQ ID NO: 1 defines a set of possible sequences. Each member of this set contains, for example, a cysteine at positions 5, 14, 30, 51 and 55, and any one of a specific set of amino acids at positions 10, 11, 13, 15, 16, 17, 18, 19, 21, 22, 23, 31, 32, 34, 35, 39, 40, 43 and 45, or positions corresponding to 25 those positions. In a preferred embodiment, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18 and/or 19 of these amino acids can be independently or collectively, in any combination, selected to correspond to the corresponding position of SEQ ID NO:2. The polypeptide preferably has at least 80%, 85%, 90%, 95, 97, 98, or 99% identity to SEQ ID NO:2. 30 The comparison of sequences and determination of percent homology between two sequences can be accomplished using a mathematical algorithm. In a preferred 42/151 embodiment, the percent homology between two amino acid sequences is determined using the Needleman and Wunsch (1970), J. Mol. Biol. 48:444-453, algorithm which has been incorporated into the GAP program in the GCG software package , using either a Blossum 62 matrix or a PAM250 matrix, and a gap weight of 16, 14, 12, 10, 8, 6, or 4 5 and a length weight of 1, 2, 3, 4, 5, or 6. In yet another preferred embodiment, the percent homology between two nucleotide sequences is determined using the GAP program in the GCG software package, using a NWSgapdna.CMP matrix and a gap weight of 40, 50, 60, 70, or 80 and a length weight of 1, 2, 3, 4, 5, or 6. A particularly preferred set of parameters (and the one that should be used if the practitioner is uncertain 10 about what parameters should be applied to determine if a molecule is within a homology limitation) are a Blossum 62 scoring matrix with a gap penalty of 12, a gap extend penalty of 4, and a frameshift gap penalty of 5. Binding Protein Inhibitors. In other embodiments, the inhibitors of kallikrein 15 are binding proteins, such as antibodies. In one aspect, the disclosure features a protein (e.g., an isolated protein) that binds to plasma kallikrein (e.g., human plasma kallikrein) and includes at least one immunoglobulin variable region. For example, the protein includes a heavy chain (HC) immunoglobulin variable domain sequence and/or a light chain (LC) immunoglobulin 20 variable domain sequence. The protein can bind to and inhibit plasma kallikrein, e.g., human plasma kallikrein. The protein can include one or more of the following characteristics: (a) a human CDR or human framework region; (b) the HC immunoglobulin variable domain sequence comprises one or more (e.g., 1, 2, or 3) CDRs that are at least 85, 88, 89, 90, 91, 25 92, 93, 94, 95, 96, 97, 98, 99, or 100% identical to a CDR of a HC variable domain described herein; (c) the LC immunoglobulin variable domain sequence comprises one or more (e.g., 1, 2, or 3) CDRs that are at least 85, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, or 100% identical to a CDR of a LC variable domain described herein; (d) the LC immunoglobulin variable domain sequence is at least 85, 88, 89, 90, 91, 92, 93, 94, 95, 30 96, 97, 98, 99, or 100% identical to a LC variable domain described herein (e.g., overall or in framework regions or CDRs); (e) the HC immunoglobulin variable domain 43/151 sequence is at least 85, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, or 100% identical to a HC variable domain described herein (e.g., overall or in framework regions or CDRs); (f) the protein binds an epitope bound by a protein described herein, or competes for binding with a protein described herein; (g) a primate CDR or primate framework region; 5 (h) the HC immunoglobulin variable domain sequence comprises a CDR1 that differs by at least one amino acid but by no more than 2 or 3 amino acids from the CDR1 of a HC variable domain described herein; (i) the HC immunoglobulin variable domain sequence comprises a CDR2 that differs by at least one amino acid but by no more than 2, 3, 4, 5, 6, 7, or 8 amino acids from the CDR2 of a HC variable domain described herein; (j) the 10 HC immunoglobulin variable domain sequence comprises a CDR3 that differs by at least one amino acid but by no more than 2, 3, 4, 5, or 6 amino acids from the CDR3 of a HC variable domain described herein; (k) the LC immunoglobulin variable domain sequence comprises a CDR1 that differs by at least one amino acid but by no more than 2, 3, 4, or 5 amino acids from the CDR1 of a LC variable domain described herein; (1) the LC 15 immunoglobulin variable domain sequence comprises a CDR2 that differs by at least one amino acid but by no more than 2, 3, or 4 amino acids from the CDR2 of a LC variable domain described herein; (m) the LC immunoglobulin variable domain sequence comprises a CDR3 that differs by at least one amino acid but by no more than 2, 3, 4, or 5 amino acids from the CDR3 of a LC variable domain described herein; (n) the LC 20 immunoglobulin variable domain sequence differs by at least one amino acid but by no more than 2, 3, 4, 5, 6, 7, 8, 9, or 10 amino acids from a LC variable domain described herein (e.g., overall or in framework regions or CDRs); and (o) the HC immunoglobulin variable domain sequence differs by at least one amino acid but by no more than 2, 3, 4, 5, 6, 7, 8, 9, or 10 amino acids from a HC variable domain described herein (e.g., overall 25 or in framework regions or CDRs). The plasma kallikrein binding protein may be an isolated protein (e.g., at least 70, 80, 90, 95, or 99% free of other proteins). The plasma kallikrein binding protein may inhibit plasma kallikrein, e.g., human plasma kallikrein. 44/151 In some embodiments, the plasma kallikrein binding protein does not bind prekallikrein (e.g., human prekallikrein), but binds to the active form of plasma kallikrein (e.g., human plasma kallikrein). In certain embodiments, the protein binds at or near the active site of the catalytic 5 domain of plasma kallikrein, or a fragment thereof, or binds an epitope that overlaps with the active site of plasma kallikrein. In some aspects, the protein binds the same epitope or competes for binding with a protein described herein. In some embodiments, the protein competes with or binds the same epitope as 10 M162-A04, M160-G12, M142-H08, X63-G06, X81-B01, X67-D03, or X67-G04. In some embodiments, the protein binds to (e.g., positions on plasma kallikrein corresponding to) CLIPS peptide Cl, C2, C3, C4, C5, C6, or C7, or more than one of these peptides, e,g., the protein binds to C5 and C6. CLIPS peptides C1-C7 are peptides in plasma kallikrein identified by CLIPS epitope mapping (see FIGURES 8 and 9A-9C). 15 C1 corresponds to positions 55-67 of the catalytic domain, C2 to positions 81-94, C3 to positions 101-108, C4 to positions 137-151, C5 to positions 162-178, C6 to positions 186-197, and C7 to positions 214-217 of plasma kallikrein. In some embodiments, the protein binds to an epitope shown in FIGURE 8. In some embodiments, the protein binds to one or more amino acids that form the 20 catalytic triad of plasma kallikrein: His434, Asp483, and/or Ser578 (numbering based on the human sequence). In some embodiments, the protein binds to one or more amino acids of Ser479, Tyr563, and/or Asp585 (numbering based on the human sequence). The active site cleft of plasma kallikrein contains three amino acids that form the 25 catalytic triad (His434, Asp483, and Ser578) and result in enzymatic hydrolysis of bound substrate (catalytic triad residues are underlined in FIGURES 9A-9C). The peptides selected for the CLIPS epitope mapping analysis were determined to be surface accessible and either form or surround the vicinity of the active site. Peptide C1 contains the active site histidine 434. Peptide C3 contains the active site aspartate 483. Peptide 30 C6 contains the active site serine 578. It is possible for an antibody to bind multiple surface exposed amino acids that are discontinuous in amino acid sequence. For 45/151 example, by CLIPs analysis, X81-BO1 appears to bind the C2, C3, C5 and the C6 peptides. In some embodiments, the protein binds to an epitope that includes one or more amino acids from CLIPS peptide C1, peptide C2, peptide C3, peptide C4, peptide C5, 5 peptide C6, or peptide C7. In some embodiments, the protein binds to an epitope that includes amino acids from at least 2 different CLIPS peptides, e.g., from at least two of peptide C1, peptide C2, peptide C3, peptide C4, peptide C5, peptide C6, or peptide C7. The protein can bind to plasma kallikrein, e.g., human plasma kallikrein, with a 10 binding affinity of at least 105, 106, 107, 108, 10', 1010 and 10" M- 1 . In one embodiment, the protein binds to human plasma kallikrein with a Kff slower than 1 X 10-3, 5X 10-4 s-1, or 1 X 10-4 S-1. In one embodiment, the protein binds to human plasma kallikrein with a

K

0 , faster than 1 X 102, 1 X 103, or 5 X 103 M-IS-1. In one embodiment, the protein binds to plasma kallikrein, but does not binds to tissue kallikrein and/or plasma prekallikrein (e.g., 15 the protein binds to tissue kallikrein and/or plasma prekallikrein less effectively (e.g., 5-, 10-, 50-, 100-, or 1000-fold less or not at all, e.g., as compared to a negative control) than it binds to plasma kallikrein. In one embodiment, the protein inhibits human plasma kallikrein activity, e.g., with a Ki of less than 10-5, 10-6, 10-7, 10- , 10- 9 , and 10-10 M. The protein can have, for 20 example, an IC50 of less than 100 nM, 10 nM or 1 nM. For example, the protein may modulate plasma kallikrein activity, as well as the production of Factor XIIa (e.g., from Factor XII) and/or bradykinin (e.g., from high-molecular-weight kininogen (HMWK)). The protein may inhibit plasma kallikrein activity, and/or the production of Factor XIIa (e.g., from Factor XII) and/or bradykinin (e.g., from high-molecular-weight kininogen 25 (HMWK)). The affinity of the protein for human plasma kallikrein can be characterized by a KD of less than 100 nm, less than 10 nM, or less than 1 nM. In one embodiment, the protein inhibits plasma kallikrein, but does not inhibits tissue kallikrein (e.g., the protein inhibits tissue kallikrein less effectively (e.g., 5-, 10-, 50-, 100-, or 1000-fold less or not at all, e.g., as compared to a negative control) than it inhibits plasma kallikrein. 30 In some embodiments, the protein has an apparent inhibition constant (Ki app) of less than 1000, 500, 100, or 10 nM. 46/151 Plasma kallikrein binding proteins may be antibodies. Plasma kallikrein binding antibodies may have their HC and LC variable domain sequences included in a single polypeptide (e.g., scFv), or on different polypeptides (e.g., IgG or Fab). In a preferred embodiment, the protein is an antibody (e.g., a human antibody) 5 having the light and heavy chains of antibodies selected from the group consisting of M162-A04, M160-G12, M142-H08, X63-G06, X81-B01, X67-D03, and X67-G04. In a preferred embodiment, the protein is an antibody (e.g., a human antibody) having the heavy chain of an antibody selected from the group consisting of: M162-A04, M160-G12, M142-H08, X63-G06, X81-B01, X67-D03, and X67-G04. 10 In a preferred embodiment, the protein is an antibody (e.g., a human antibody) having the light chain of an antibody selected from the group consisting of: M162-A04, M160-G12, M142-H08, X63-G06, X81-B01, X67-D03, and X67-G04. In a preferred embodiment, the protein is an antibody (e.g., a human antibody) having light and heavy antibody variable regions of an antibody selected from the group 15 consisting of M162-A04, M160-G12, M142-H08, X63-G06, X81-B01, X67-D03, and X67-G04. In a preferred embodiment, the protein is an antibody (e.g., a human antibody) having a heavy chain antibody variable region of an antibody selected from the group consisting of: M162-A04, M160-G12, M142-H08, X63-G06, X81-B01, X67-D03, and 20 X67-G04. In a preferred embodiment, the protein is an antibody (e.g., a human antibody) having a light chain antibody variable region of an antibody selected from the group consisting of: M162-A04, M160-G12, M142-H08, X63-G06, X81-B01, X67-D03, and X67-G04. 25 In a preferred embodiment, the protein is an antibody (e.g., a human antibody) having one or more (e.g., 1, 2, or 3) heavy chain CDRs selected from the corresponding CDRs of the group of heavy chains consisting of M162-A04, M160-G12, M142-H08, X63-G06, X81-B01, X67-D03, and X67-G04. In a preferred embodiment, the protein is an antibody (e.g., a human antibody) 30 having one or more (e.g., 1, 2, or 3) light chain CDRs selected from the corresponding 47/151 CDRs of the group of light chains consisting of M162-A04, M160-G12, M142-H08, X63-G06, X81-B01, X67-D03, and X67-G04. In a preferred embodiment, the protein is an antibody (e.g., a human antibody) having one or more (e.g., 1, 2, or 3) heavy chain CDRs and one or more (e.g., 1, 2, or 3) 5 light chain CDRs selected from the corresponding CDRs of the group of light chains consisting of M162-A04, M160-G12, M142-H08, X63-G06, X81-B01, X67-D03, and X67-G04. In one embodiment, the HC and LC variable domain sequences are components of the same polypeptide chain. In another, the HC and LC variable domain sequences are 10 components of different polypeptide chains. For example, the protein is an IgG., e.g., IgGI, IgG2, IgG3, or IgG4. The protein can be a soluble Fab. In other implementations the protein includes a Fab2, scFv, minibody, scFv::Fc fusion, Fab::HSA fusion, HSA::Fab fusion, Fab::HSA::Fab fusion, or other molecule that comprises the antigen combining site of one of the binding proteins herein. The VH and VL regions of these 15 Fabs can be provided as IgG, Fab, Fab2, Fab2, scFv, PEGylated Fab, PEGylated scFv, PEGylated Fab2, VH::CH1::HSA+LC, HSA::VH::CH1+LC, LC::HSA + VH::CH1, HSA::LC + VH::CH1, or other appropriate construction. In one embodiment, the protein is a human or humanized antibody or is non immunogenic in a human. For example, the protein includes one or more human 20 antibody framework regions, e.g., all human framework regions, or framework regions at least 85, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99% identical to human framework regions. In one embodiment, the protein includes a human Fc domain, or an Fc domain that is at least 95, 96, 97, 98, or 99% identical to a human Fc domain. In one embodiment, the protein is a primate or primatized antibody or is non 25 immunogenic in a human. For example, the protein includes one or more primate antibody framework regions, e.g., all primate framework regions, or framework regions at least 85, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99% identical to primate framework regions. In one embodiment, the protein includes a primate Fc domain, or an Fc domain that is at least 95, 96, 97, 98, or 99% identical to a primate Fc domain. "Primate" 30 includes humans (Homo sapiens), chimpanzees (Pan troglodytes and Pan paniscus 48/151 (bonobos)), gorillas (Gorilla gorilla), gibons, monkeys, lemurs, aye-ayes (Daubentonia madagascariensis), and tarsiers. In some embodiments, the affinity of the primate antibody for human plasma kallikrein is characterized by a KD of less than 1000, 500, 100 or 10 nM, e.g., .less than 5 10 nM or less than 1 nM. In certain embodiments, the protein includes no sequences from mice or rabbits (e.g., is not a murine or rabbit antibody). In some aspects, the disclosure provides the use of proteins (e.g., binding proteins, e.g., antibodies) (e.g., the proteins described herein) that bind to plasma kallikrein (e.g., 10 human plasma kallikrein) and include at least one immunoglobin variable region in methods for treating (or preventing) mucositis. For example, the plasma kallikrein binding protein includes a heavy chain (HC) immunoglobulin variable domain sequence and a light chain (LC) immunoglobulin variable domain sequence. A number of exemplary plasma kallikrein binding proteins are described herein. 15 Antibodies may be discovered by screening a library using a kallikrein target, as well as by other methods. For example, kallikrein protein or a region thereof can be used as an antigen in a non-human animal, e.g., a rodent. Humanized antibodies can be generated by replacing sequences of the Fv variable region that are not directly involved in antigen binding with equivalent sequences from human Fv variable regions. General 20 methods for generating humanized antibodies are provided by Morrison, S. L., 1985, Science 229:1202-1207, by Oi et al., 1986, BioTechniques 4:214, and by Queen et al. US Patent Nos. 5,585,089, US 5,693,761 and US 5,693,762. Those methods include isolating, manipulating, and expressing the nucleic acid sequences that encode all or part of immunoglobulin Fv variable regions from at least one of a heavy or light chain. 25 Numerous sources of such nucleic acid are available. For example, nucleic acids may be obtained from a hybridoma producing an antibody against a predetermined target, as described above. The recombinant DNA encoding the humanized antibody, or fragment thereof, can then be cloned into an appropriate expression vector. Immunoglobin kallikrein binding proteins (e.g., IgG or Fab kallikrein binding 30 proteins) may be modified to reduce immunogenicity. Reduced immunogenicity is desirable in kallikrein binding proteins intended for use as therapeutics, as it reduces the 49/151 chance that the subject will develop an immune response against the therapeutic molecule. Techniques useful for reducing immunogenicity of kallikrein binding proteins include deletion/modification of potential human T cell epitopes and 'germlining' of sequences outside of the CDRs (e.g., framework and Fc). 5 A kallikrein-binding antibody may be modified by specific deletion of human T cell epitopes or "deimmunization" by the methods disclosed in WO 98/52976 and WO 00/34317. Briefly, the heavy and light chain variable regions of an antibody are analyzed for peptides that bind to MHC Class II; these peptides represent potential T-cell epitopes (as defined in WO 98/52976 and WO 00/34317). For detection of potential T-cell 10 epitopes, a computer modeling approach termed "peptide threading" can be applied, and in addition a database of human MHC class II binding peptides can be searched for motifs present in the VH and VL sequences, as described in WO 98/52976 and WO 00/34317. These motifs bind to any of the 18 major MHC class II DR allotypes, and thus constitute potential T cell epitopes. Potential T-cell epitopes detected can be eliminated 15 by substituting small numbers of amino acid residues in the variable regions, or preferably, by single amino acid substitutions. As far as possible conservative substitutions are made, often but not exclusively, an amino acid common at this position in human germline antibody sequences may be used. Human germline sequences are disclosed in Tomlinson, I.A. et al., 1992, J. Mol. Biol. 227:776-798; Cook, G. P. et al., 20 1995, Immunol. Today Vol. 16 (5): 237-242; Chothia, D. et al., 1992, J. Mol. Bio. 227:799-817. The V BASE directory provides a comprehensive directory of human immunoglobulin variable region sequences (compiled by Tomlinson, I.A. et al. MRC Centre for Protein Engineering, Cambridge, UK). After the deimmunizing changes are identified, nucleic acids encoding VH and VL can be constructed by mutagenesis or other 25 synthetic methods (e.g., de novo synthesis, cassette replacement, and so forth). Mutagenized variable sequence can, optionally, be fused to a human constant region, e.g., human IgGI or iK constant regions. In some cases a potential T cell epitope will include residues which are known or predicted to be important for antibody function. For example, potential T cell epitopes 30 are usually biased towards the CDRs. In addition, potential T cell epitopes can occur in framework residues important for antibody structure and binding. Changes to eliminate 50/151 these potential epitopes will in some cases require more scrutiny, e.g., by making and testing chains with and without the change. Where possible, potential T cell epitopes that overlap the CDRs were eliminated by substitutions outside the CDRs. In some cases, an alteration within a CDR is the only option, and thus variants with and without this 5 substitution should be tested. In other cases, the substitution required to remove a potential T cell epitope is at a residue position within the framework that might be critical for antibody binding. In these cases, variants with and without this substitution should be tested. Thus, in some cases several variant deimmunized heavy and light chain variable regions were designed and various heavy/light chain combinations tested in order to 10 identify the optimal deimmunized antibody. The choice of the final deimmunized antibody can then be made by considering the binding affinity of the different variants in conjunction with the extent of deimmunization, i.e., the number of potential T cell epitopes remaining in the variable region. Deimmunization can be used to modify any antibody, e.g., an antibody that includes a non-human sequence, e.g., a synthetic 15 antibody, a murine antibody other non-human monoclonal antibody, or an antibody isolated from a display library. Kallikrein binding antibodies are "germlined" by reverting one or more non germline amino acids in framework regions to corresponding germline amino acids of the antibody, so long as binding properties are substantially retained. Similar methods can 20 also be used in the constant region, e.g., in constant immunoglobulin domains. Antibodies that bind to kallikrein, e.g., an antibody described herein, may be modified in order to make the variable regions of the antibody more similar to one or more germline sequences. For example, an antibody can include one, two, three, or more amino acid substitutions, e.g., in a framework, CDR, or constant region, to make it more 25 similar to a reference germline sequence. One exemplary germlining method can include identifying one or more germline sequences that are similar (e.g., most similar in a particular database) to the sequence of the isolated antibody. Mutations (at the amino acid level) are then made in the isolated antibody, either incrementally or in combination with other mutations. For example, a nucleic acid library that includes sequences 30 encoding some or all possible germline mutations is made. The mutated antibodies are then evaluated, e.g., to identify an antibody that has one or more additional germline 51/151 residues relative to the isolated antibody and that is still useful (e.g., has a functional activity). In one embodiment, as many germline residues are introduced into an isolated antibody as possible. In one embodiment, mutagenesis is used to substitute or insert one or more 5 germline residues into a framework and/or constant region. For example, a germline framework and/or constant region residue can be from a germline sequence that is similar (e.g., most similar) to the non-variable region being modified. After mutagenesis, activity (e.g., binding or other functional activity) of the antibody can be evaluated to determine if the germline residue or residues are tolerated (i.e., do not abrogate activity). 10 Similar mutagenesis can be performed in the framework regions. Selecting a germline sequence can be performed in different ways. For example, a germline sequence can be selected if it meets a predetermined criteria for selectivity or similarity, e.g., at least a certain percentage identity, e.g., at least 75, 80, 85, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, or 99.5% identity. The selection can be performed using at 15 least 2, 3, 5, or 10 germline sequences. In the case of CDR1 and CDR2, identifying a similar germline sequence can include selecting one such sequence. In the case of CDR3, identifying a similar germline sequence can include selecting one such sequence, but may including using two germline sequences that separately contribute to the amino-terminal portion and the carboxy-terminal portion. In other implementations more than one or two 20 germline sequences are used, e.g., to form a consensus sequence. In one embodiment, with respect to a particular reference variable domain sequence, e.g., a sequence described herein, a related variable domain sequence has at least 30, 40, 50, 60, 70, 80, 90, 95 or 100% of the CDR amino acid positions that are not identical to residues in the reference CDR sequences, residues that are identical to 25 residues at corresponding positions in a human germline sequence (i.e., an amino acid sequence encoded by a human germline nucleic acid). In one embodiment, with respect to a particular reference variable domain sequence, e.g., a sequence described herein, a related variable domain sequence has at least 30, 50, 60, 70, 80, 90 or 100% of the FR regions identical to FR sequence from a 30 human germline sequence, e.g., a germline sequence related to the reference variable domain sequence. 52/151 Accordingly, it is possible to isolate an antibody which has similar activity to a given antibody of interest, but is more similar to one or more germline sequences, particularly one or more human germline sequences. For example, an antibody can be at least 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, or 99.5% identical to a germline sequence in a 5 region outside the CDRs (e.g., framework regions). Further, an antibody can include at least 1, 2, 3, 4, or 5 germline residues in a CDR region, the germline residue being from a germline sequence of similar (e.g., most similar) to the variable region being modified. Germline sequences of primary interest are human germline sequences. The activity of the antibody (e.g., the binding activity as measured by KA) can be within a factor or 100, 10 10, 5, 2, 0.5, 0.1, and 0.001 of the original antibody. Germline sequences of human immunoglobin genes have been determined and are available from a number of sources, including the international ImMunoGeneTics information system@ (IMGT), available via the world wide web at imgt.cines.fr, and the V BASE directory (compiled by Tomlinson, I.A. et al. MRC Centre for Protein 15 Engineering, Cambridge, UK, available via the world wide web at vbase.mrc cpe.cam.ac.uk). Exemplary germline reference sequences for Vkappa include: 012/02, 018/08, A20, A30, L14, LI, L15, L4/18a, L5/L19, L8, L23, L9 ,L24, LI1, L12, 011/01, A17, Al, A18, A2, A19/A3, A23, A27, All, L2/L16, L6, L20, L25, B3, B2, A26/A1O, and 20 A14. See, e.g., Tomlinson et al., 1995, EMBO J. 14(18):4628-3. A germline reference sequence for the HC variable domain can be based on a sequence that has particular canonical structures, e.g., 1-3 structures in the HI and H2 hypervariable loops. The canonical structures of hypervariable loops of an immunoglobulin variable domain can be inferred from its sequence, as described in 25 Chothia et al., 1992, J. Mol. Biol. 227:799-817; Tomlinson et al., 1992, J. Mol. Biol. 227:776-798); and Tomlinson et al., 1995, EMBO J. 14(18):4628-38. Exemplary sequences with a 1-3 structure include: DP-I, DP-8, DP-12, DP-2, DP-25, DP-15, DP-7, DP-4, DP-31, DP-32, DP-33, DP-35, DP-40, 7-2, hv3005, hv3005f3, DP-46, DP-47, DP 58, DP-49, DP-50, DP-51, DP-53, and DP-54. 30 Useful polypeptides can also be encoded by a nucleic acid that hybridizes to a nucleic acid that encodes a polypeptide described herein. The nucleic acids can hybridize 53/151 under medium, high, or very high stringency conditions. As used herein, the term "hybridizes under low stringency, medium stringency, high stringency, or very high stringency conditions" describes conditions for hybridization and washing. Guidance for performing hybridization reactions can be found in Current Protocols in Molecular 5 Biology, John Wiley & Sons, N.Y. (1989), 6.3.1-6.3.6, which is incorporated by reference. Aqueous and nonaqueous methods are described in that reference and either can be used. Specific hybridization conditions referred to herein are as follows: (1) low stringency hybridization conditions in 6X sodium chloride/sodium citrate (SSC) at about 45'C, followed by two washes in 0.2X SSC, 0.1% SDS at least at 50'C (the temperature 10 of the washes can be increased to 55'C for low stringency conditions); (2) medium stringency hybridization conditions in 6X SSC at about 45'C, followed by one or more washes in 0.2X SSC, 0.1% SDS at 60'C; (3) high stringency hybridization conditions in 6X SSC at about 45'C, followed by one or more washes in 0.2X SSC, 0.1% SDS at 65'C; and (4) very high stringency hybridization conditions are 0.5M sodium phosphate, 15 7% SDS at 65'C, followed by one or more washes at 0.2X SSC, 1% SDS at 65'C. Protein Production. Standard recombinant nucleic acid methods can be used to express a protein that binds to plasma kallikrein. Generally, a nucleic acid sequence encoding the protein is cloned into a nucleic acid expression vector. Of course, if the protein includes multiple polypeptide chains, each chain can be cloned into an expression 20 vector, e.g., the same or different vectors, that are expressed in the same or different cells. Antibody Production. Some antibodies, e.g., Fabs, can be produced in bacterial cells, e.g., E. coli cells. For example, if the Fab is encoded by sequences in a phage display vector that includes a suppressible stop codon between the display entity and a bacteriophage protein (or fragment thereof), the vector nucleic acid can be transferred 25 into a bacterial cell that cannot suppress a stop codon. In this case, the Fab is not fused to the gene III protein and is secreted into the periplasm and/or media. Antibodies can also be produced in eukaryotic cells. In one embodiment, the antibodies (e.g., scFv's) are expressed in a yeast cell such as Pichia (see, e.g., Powers et al., 2001, J. Immunol. Methods. 251:123-35), Hanseula, or Saccharomyces. 54/151 In one preferred embodiment, antibodies are produced in mammalian cells. Preferred mammalian host cells for expressing the clone antibodies or antigen-binding fragments thereof include Chinese Hamster Ovary (CHO cells) (including dhfr- CHO cells, described in Urlaub and Chasin, 1980, Proc. Natl. Acad. Sci. USA 77:4216-4220, 5 used with a DHFR selectable marker, e.g., as described in Kaufman and Sharp, 1982, Mol. Biol. 159:601 621), lymphocytic cell lines, e.g., NSO myeloma cells and SP2 cells, COS cells, HEK293T cells (J. Immunol. Methods (2004) 289(1-2):65-80), and a cell from a transgenic animal, e.g., a transgenic mammal. For example, the cell is a mammary epithelial cell. 10 In addition to the nucleic acid sequence encoding the diversified immunoglobulin domain, the recombinant expression vectors may carry additional sequences, such as sequences that regulate replication of the vector in host cells (e.g., origins of replication) and selectable marker genes. The selectable marker gene facilitates selection of host cells into which the vector has been introduced (see e.g., U.S. Patent Nos. 4,399,216, 15 4,634,665 and 5,179,017). For example, typically the selectable marker gene confers resistance to drugs, such as G418, hygromycin or methotrexate, on a host cell into which the vector has been introduced. Preferred selectable marker genes include the dihydrofolate reductase (DHFR) gene (for use in dhfr host cells with methotrexate selection/amplification) and the neo gene (for G418 selection). 20 In an exemplary system for recombinant expression of an antibody, or antigen binding portion thereof, a recombinant expression vector encoding both the antibody heavy chain and the antibody light chain is introduced into dhfr- CHO cells by calcium phosphate-mediated transfection. Within the recombinant expression vector, the antibody heavy and light chain genes are each operatively linked to enhancer/promoter 25 regulatory elements (e.g., derived from SV40, CMV, adenovirus and the like, such as a CMV enhancer/AdMLP promoter regulatory element or an SV40 enhancer/AdMLP promoter regulatory element) to drive high levels of transcription of the genes. The recombinant expression vector also carries a DHFR gene, which allows for selection of CHO cells that have been transfected with the vector using methotrexate 30 selection/amplification. The selected transformant host cells are cultured to allow for expression of the antibody heavy and light chains and intact antibody is recovered from 55/151 the culture medium. Standard molecular biology techniques are used to prepare the recombinant expression vector, transfect the host cells, select for transformants, culture the host cells and recover the antibody from the culture medium. For example, some antibodies can be isolated by affinity chromatography with a Protein A or Protein G 5 coupled matrix. For antibodies that include an Fc domain, the antibody production system may produce antibodies in which the Fc region is glycosylated. For example, the Fc domain of IgG molecules is glycosylated at asparagine 297 in the CH2 domain. This asparagine is the site for modification with biantennary-type oligosaccharides. It has been 10 demonstrated that this glycosylation is required for effector functions mediated by Fcg receptors and complement Clq (Burton and Woof, 1992, Adv. Immunol. 51:1-84; Jefferis et al., 1998, Immunol. Rev. 163:59-76). In one embodiment, the Fc domain is produced in a mammalian expression system that appropriately glycosylates the residue corresponding to asparagine 297. The Fc domain can also include other eukaryotic post 15 translational modifications. Antibodies can also be produced by a transgenic animal. For example, U.S. Pat. No. 5,849,992 describes a method of expressing an antibody in the mammary gland of a transgenic mammal. A transgene is constructed that includes a milk-specific promoter and nucleic acids encoding the antibody of interest and a signal sequence for secretion. 20 The milk produced by females of such transgenic mammals includes, secreted-therein, the antibody of interest. The antibody can be purified from the milk, or for some applications, used directly. Plasma Kallikrein 25 Exemplary plasma kallikrein sequences against which plasma kallikrein binding proteins may be developed can include human, mouse, or rat plasma kallikrein amino acid sequences, a sequence that is 80%, 85%, 90%, 95%, 96%, 97%, 98%, or 99% identical to one of these sequences, or a fragment thereof, e.g., of a sequence provided below. 56/151 The sequence of human plasma kallikrein that was used in selections and subsequent screening of binding proteins is shown below (accession number NP_000883.2). The human plasma kallikrein (86 kDa) that was used was purified from human plasma and activated with factor XIIa by a commercial vendor. Factor XIIa 5 activates prekallikrein by cleaving the polypeptide sequence at a single site (between Arg371-Ile372, cleavage site marked by "/" in the sequence below) to generate active plasma kallikrein, which then consists of two disulfide linked polypeptides; a heavy chain of approximately 52 kDa and a catalytic domain of approximately 34 kDa [Colman and Schmaier, (1997) "Contact System: A Vascular Biology Modulator With Anticoagulant, 10 Profibrinolytic, Antiadhesive, and Proinflammatory Attributes" Blood, 90, 3819-3843] GCLTQLYENAFFRGGDVASMYTPNAQYCQMRCTFHPRCLLFSFLPASSINDMEKRFGCFLKDSVTGTLPKV HRTGAVSGHSLKQCGHQISACHRDIYKGVDMRGVNFNVSKVSSVEECQKRCTSNIRCQFFSYATQTFHKAE YRNNCLLKYSPGGTPTAIKVLSNVESGFSLKPCALSEIGCHMNIFQHLAFSDVDVARVLTPDAFVCRTICT 15 YHPNCLFFTFYTNVWKIESQRNVCLLKTSESGTPSSSTPQENTISGYSLLTCKRTLPEPCHSKIYPGVDFG GEELNVTFVKGVNVCQETCTKMIRCQFFTYSLLPEDCKEEKCKCFLRLSMDGSPTRIAYGTQGSSGYSLRL CNTGDNSVCTTKTSTR/IVGGTNSSWGEWPWQVSLQVKLTAQRHLCGGSLIGHQWVLTAAHCFDGLPLQDV WRIYSGILNLSDITKDTPFSQIKEIIIIHQNYKVSEGNHDIALIKLQAPLNYTEFQKPICLPSKGDTSTIYT NCWVTGWGFSKEKGEIQNILQKVNIPLVTNEECQKRYQDYKITQRMVCAGYKEGGKDACKGDSGGPLVCKH 20 NGMWRLVGITSWGEGCARREQPGVYTKVAEYMDWILEKTQSSDGKAQMQSPA The human, mouse, and rat prekallikrein amino acid sequences, and the mRNA sequences encoding the same, are illustrated below. The sequences of prekallikrein are the same as plasma kallikrein, except that active plasma kallikrein (pkal) has the single 25 polypeptide chain cleaved at a single position (indicated by the "/") to generate two chains. The sequences provided below are full sequences that include signal sequences. On secretion from the expressing cell, it is expected that the signal sequences are removed. 30 Human plasma kallikrein (ACCESSION: NP_000883.2) >gil78191798IrefINP_000883.21 plasma kallikrein B1 precursor [Homo sapiens] MILFKQATYFISLFATVSCGCLTQLYENAFFRGGDVASMYTPNAQYCQMRCTFHPRCLLFSFLPASSIND MEKRFGCFLKDSVTGTLPKVHRTGAVSGHSLKQCGHQISACHRDIYKGVDMRGVNFNVSKVSSVEECQKR 35 CTSNIRCQFFSYATQTFHKAEYRNNCLLKYSPGGTPTAIKVLSNVESGFSLKPCALSEIGCHMNIFQHLA FSDVDVARVLTPDAFVCRTICTYHPNCLFFTFYTNVWKIESQRNVCLLKTSESGTPSSSTPQENTISGYS LLTCKRTLPEPCHSKIYPGVDFGGEELNVTFVKGVNVCQETCTKMIRCQFFTYSLLPEDCKEEKCKCFLR LSMDGSPTRIAYGTQGSSGYSLRLCNTGDNSVCTTKTSTRIVGGTNSSWGEWPWQVSLQVKLTAQRHLCG GSLIGHQWVLTAAHCFDGLPLQDVWRIYSGILNLSDITKDTPFSQIKEIIIHQNYKVSEGNHDIALIKLQ 40 APLNYTEFQKPICLPSKGDTSTIYTNCWVTGWGFSKEKGEIQNILQKVNIPLVTNEECQKRYQDYKITQR 57/151 MVCAGYKEGGKDACKGDSGGPLVCKHNGMWRLVGITSWGEGCARREQPGVYTKVAEYMDWILEKTQSSDG KAQMQSPA Human plasma kallikrein mRNA (ACCESSION: NM_000892) 5 >gil78191797|refINM_000892.31 Homo sapiens kallikrein B, plasma (Fletcher factor) 1 (KLKB1), mRNA AGAACAGCTTGAAGACCGTTCATTTTTAAGTGACAAGAGACTCACCTCCAAGAAGCAATTGTGTTTTCAG AATGATTTTATTCAAGCAAGCAACTTATTTCATTTCCTTGTTTGCTACAGTTTCCTGTGGATGTCTGACT CAACTCTATGAAAACGCCTTCTTCAGAGGTGGGGATGTAGCTTCCATGTACACCCCAAATGCCCAATACT 10 GCCAGATGAGGTGCACATTCCACCCAAGGTGTTTGCTATTCAGTTTTCTTCCAGCAAGTTCAATCAATGA CATGGAGAAAAGGTTTGGTTGCTTCTTGAAAGATAGTGTTACAGGAACCCTGCCAAAAGTACATCGAACA GGTGCAGTTTCTGGACATTCCTTGAAGCAATGTGGTCATCAAATAAGTGCTTGCCATCGAGACATTTATA AAGGAGTTGATATGAGAGGAGTCAATTTTAATGTGTCTAAGGTTAGCAGTGTTGAAGAATGCCAAAAAAG GTGCACCAGTAACATTCGCTGCCAGTTTTTTTCATATGCCACGCAAACATTTCACAAGGCAGAGTACCGG 15 AACAATTGCCTATTAAAGTACAGTCCCGGAGGAACACCTACCGCTATAAAGGTGCTGAGTAACGTGGAAT CTGGATTCTCACTGAAGCCCTGTGCCCTTTCAGAAATTGGTTGCCACATGAACATCTTCCAGCATCTTGC GTTCTCAGATGTGGATGTTGCCAGGGTTCTCACTCCAGATGCTTTTGTGTGTCGGACCATCTGCACCTAT CACCCCAACTGCCTCTTCTTTACATTCTATACAAATGTATGGAAAATCGAGTCACAAAGAAATGTTTGTC TTCTTAAAACATCTGAAAGTGGCACACCAAGTTCCTCTACTCCTCAAGAAAACACCATATCTGGATATAG 20 CCTTTTAACCTGCAAAAGAACTTTACCTGAACCCTGCCATTCTAAAATTTACCCGGGAGTTGACTTTGGA GGAGAAGAATTGAATGTGACTTTTGTTAAAGGAGTGAATGTTTGCCAAGAGACTTGCACAAAGATGATTC GCTGTCAGTTTTTCACTTATTCTTTACTCCCAGAAGACTGTAAGGAAGAGAAGTGTAAGTGTTTCTTAAG ATTATCTATGGATGGTTCTCCAACTAGGATTGCGTATGGGACACAAGGGAGCTCTGGTTACTCTTTGAGA TTGTGTAACACTGGGGACAACTCTGTCTGCACAACAAAAACAAGCACACGCATTGTTGGAGGAACAAACT 25 CTTCTTGGGGAGAGTGGCCCTGGCAGGTGAGCCTGCAGGTGAAGCTGACAGCTCAGAGGCACCTGTGTGG AGGGTCACTCATAGGACACCAGTGGGTCCTCACTGCTGCCCACTGCTTTGATGGGCTTCCCCTGCAGGAT GTTTGGCGCATCTATAGTGGCATTTTAAATCTGTCAGACATTACAAAAGATACACCTTTCTCACAAATAA AAGAGATTATTATTCACCAAAACTATAAAGTCTCAGAAGGGAATCATGATATCGCCTTGATAAAACTCCA GGCTCCTTTGAATTACACTGAATTCCAAAAACCAATATGCCTACCTTCCAAAGGTGACACAAGCACAATT 30 TATACCAACTGTTGGGTAACCGGATGGGGCTTCTCGAAGGAGAAAGGTGAAATCCAAAATATTCTACAAA AGGTAAATATTCCTTTGGTAACAAATGAAGAATGCCAGAAAAGATATCAAGATTATAAAATAACCCAACG GATGGTCTGTGCTGGCTATAAAGAAGGGGGAAAAGATGCTTGTAAGGGAGATTCAGGTGGTCCCTTAGTT TGCAAACACAATGGAATGTGGCGTTTGGTGGGCATCACCAGCTGGGGTGAAGGCTGTGCCCGCAGGGAGC AACCTGGTGTCTACACCAAAGTCGCTGAGTACATGGACTGGATTTTAGAGAAAACACAGAGCAGTGATGG 35 AAAAGCTCAGATGCAGTCACCAGCATGAGAAGCAGTCCAGAGTCTAGGCAATTTTTACAACCTGAGTTCA AGTCAAATTCTGAGCCTGGGGGGTCCTCATCTGCAAAGCATGGAGAGTGGCATCTTCTTTGCATCCTAAG GACGAAAAACACAGTGCACTCAGAGCTGCTGAGGACAATGTCTGGCTGAAGCCCGCTTTCAGCACGCCGT AACCAGGGGCTGACAATGCGAGGTCGCAACTGAGATCTCCATGACTGTGTGTTGTGAAATAAAATGGTGA AAGATCAAAAAA 40 Mouse plasma kallikrein (ACCESSION: NP_032481.1) >gil6680584|refINP_032481.11 kallikrein B, plasma 1 [Mus musculus] MILFNRVGYFVSLFATVSCGCMTQLYKNTFFRGGDLAAIYTPDAQYCQKMCTFHPRCLLFSFLAVTPPKE TNKRFGCFMKESITGTLPRIHRTGAISGHSLKQCGHQISACHRDIYKGLDMRGSNFNISKTDNIEECQKL 45 CTNNFHCQFFTYATSAFYRPEYRKKCLLKHSASGTPTSIKSADNLVSGFSLKSCALSEIGCPMDIFQHSA FADLNVSQVITPDAFVCRTICTFHPNCLFFTFYTNEWETESQRNVCFLKTSKSGRPSPPIPQENAISGYS LLTCRKTRPEPCHSKIYSGVDFEGEELNVTFVQGADVCQETCTKTIRCQFFIYSLLPQDCKEEGCKCSLR LSTDGSPTRITYGMQGSSGYSLRLCKLVDSPDCTTKINARIVGGTNASLGEWPWQVSLQVKLVSQTHLCG GSIIGRQWVLTAAHCFDGIPYPDVWRIYGGILSLSEITKETPSSRIKELIIHQEYKVSEGNYDIALIKLQ 50 TPLNYTEFQKPICLPSKADTNTIYTNCWVTGWGYTKEQGETQNILQKATIPLVPNEECQKKYRDYVINKQ MICAGYKEGGTDACKGDSGGPLVCKHSGRWQLVGITSWGEGCGRKDQPGVYTKVSEYMDWILEKTQSSDV RALETSSA 58/151 Mouse plasma kallikrein mRNA (ACCESSION: NM_008455.2) >gil2364658041reflNM_008455.21 Mus musculus kallikrein B, plasma 1 (Klkbl), mRNA AGACCGCCCTCGGTGCCATATTCAGAGGGCTTGAAGACCATCTTCATGTGAAGACTCCCTCTCCTCCAGA 5 ACCACAACGTGACCATCCTTCCAGGATGATTTTATTCAACCGAGTGGGTTATTTTGTTTCCTTGTTTGCT ACCGTCTCCTGTGGGTGTATGACTCAACTGTATAAAAATACCTTCTTCAGAGGTGGGGATCTAGCTGCCA TCTACACCCCAGATGCCCAGTACTGTCAGAAGATGTGCACTTTTCACCCCAGGTGCCTGCTGTTCAGCTT TCTCGCCGTGACTCCACCCAAAGAGACAAATAAACGGTTTGGTTGCTTCATGAAAGAGAGCATTACAGGG ACTTTGCCAAGAATACACCGGACAGGGGCCATTTCTGGTCATTCTTTAAAGCAGTGTGGCCATCAAATAA 10 GTGCTTGCCACCGAGACATATACAAAGGACTTGATATGAGAGGGTCCAACTTTAATATCTCTAAGACCGA CAATATTGAAGAATGCCAGAAACTGTGCACAAATAATTTTCACTGCCAATTTTTCACATATGCTACAAGT GCATTTTACAGACCAGAGTACCGGAAGAAGTGCCTGCTGAAGCACAGTGCAAGCGGAACACCCACCAGCA TAAAGTCAGCGGACAACCTGGTGTCTGGATTCTCACTGAAGTCCTGTGCGCTTTCGGAGATAGGTTGCCC CATGGATATTTTCCAGCACTCTGCCTTTGCAGACCTGAATGTAAGCCAGGTCATCACCCCCGATGCCTTT 15 GTGTGTCGCACCATCTGCACCTTCCATCCCAACTGCCTTTTCTTCACGTTCTACACGAATGAATGGGAGA CAGAATCACAGAGAAATGTTTGTTTTCTTAAGACGTCTAAAAGTGGAAGACCAAGTCCCCCTATTCCTCA AGAAAACGCTATATCTGGATATAGTCTCCTCACCTGCAGAAAAACTCGCCCTGAACCCTGCCATTCCAAA ATTTACTCTGGAGTTGACTTTGAAGGGGAAGAACTGAATGTGACCTTCGTGCAAGGAGCAGATGTCTGCC AAGAGACTTGTACAAAGACAATCCGCTGCCAGTTTTTTATTTACTCCTTACTCCCCCAAGACTGCAAGGA 20 GGAGGGGTGTAAATGTTCCTTAAGGTTATCCACAGATGGCTCCCCAACTAGGATCACCTATGGCATGCAG GGGAGCTCCGGTTATTCTCTGAGATTGTGTAAACTTGTGGACAGCCCTGACTGTACAACAAAAATAAATG CACGTATTGTGGGAGGAACAAACGCTTCTTTAGGGGAGTGGCCATGGCAGGTCAGCCTGCAAGTGAAGCT GGTATCTCAGACCCATTTGTGTGGAGGGTCCATCATTGGTCGCCAATGGGTACTGACAGCTGCCCATTGC TTTGATGGAATTCCCTATCCAGATGTGTGGCGTATATATGGCGGAATTCTTAGTCTGTCCGAGATTACGA 25 AAGAAACGCCTTCCTCGAGAATAAAGGAGCTTATTATTCATCAGGAATACAAAGTCTCAGAAGGCAATTA TGATATTGCCTTAATAAAGCTTCAGACGCCCCTGAATTATACTGAATTCCAAAAACCAATATGCCTGCCT TCCAAAGCTGACACAAATACAATTTATACCAACTGTTGGGTGACTGGATGGGGCTACACGAAGGAACAAG GTGAAACGCAAAATATTCTACAAAAGGCTACTATTCCTTTGGTACCAAATGAAGAATGCCAGAAAAAATA CAGAGATTATGTTATAAACAAGCAGATGATCTGTGCTGGCTACAAAGAAGGCGGAACAGACGCTTGTAAG 30 GGAGATTCCGGTGGCCCCTTAGTCTGTAAACACAGTGGACGGTGGCAGTTGGTGGGTATCACCAGCTGGG GTGAAGGCTGCGCCCGCAAGGACCAACCAGGAGTCTACACCAAAGTTTCTGAGTACATGGACTGGATATT GGAGAAGACACAGAGCAGTGATGTAAGAGCTCTGGAGACATCTTCAGCCTGAGGAGGCTGGGTACCAAGG AGGAAGAACCCAGCTGGCTTTACCACCTGCCCTCAAGGCAAACTAGAGCTCCAGGATTCTCGGCTGTAAA ATGTTGATAATGGTGTCTACCTCACATCCGTATCATTGGATTGAAAATTCAAGTGTAGATATAGTTGCTG 35 AAGACAGCGTTTTGCTCAAGTGTGTTTCCTGCCTTGAGTCACAGGAGCTCCAATGGGAGCATTACAAAGA TCACCAAGCTTGTTAGGAAAGAGAATGATCAAAGGGTTTTATTAGGTAATGAAATGTCTAGATGTGATGC AATTGAAAAAAAGACCCCAGATTCTAGCACAGTCCTTGGGACCATTCTCATGTAACTGTTGACTCTGGAC CTCAGCAGATCTCAGAGTTACCTGTCCACTTCTGACATTTGTTTATTAGAGCCTGATGCTATTCTTTCAA GTGGAGCAAAAAAAAAAAAAAA 40 Rat plasma kallikrein (ACCESSION: NP_036857.2) >gill62138905|refINP_036857.21 kallikrein B, plasma 1 [Rattus norvegicus] MILFKQVGYFVSLFATVSCGCLSQLYANTFFRGGDLAAIYTPDAQHCQKMCTFHPRCLLFSFLAVSPTKE 45 TDKRFGCFMKESITGTLPRIHRTGAISGHSLKQCGHQLSACHQDIYEGLDMRGSNFNISKTDSIEECQKL CTNNIHCQFFTYATKAFHRPEYRKSCLLKRSSSGTPTSIKPVDNLVSGFSLKSCALSEIGCPMDIFQHFA FADLNVSHVVTPDAFVCRTVCTFHPNCLFFTFYTNEWETESQRNVCFLKTSKSGRPSPPIIQENAVSGYS LFTCRKARPEPCHFKIYSGVAFEGEELNATFVQGADACQETCTKTIRCQFFTYSLLPQDCKAEGCKCSLR LSTDGSPTRITYEAQGSSGYSLRLCKVVESSDCTTKINARIVGGTNSSLGEWPWQVSLQVKLVSQNHMCG 50 GSIIGRQWILTAAHCFDGIPYPDVWRIYGGILNLSEITNKTPFSSIKELIIHQKYKMSEGSYDIALIKLQ TPLNYTEFQKPICLPSKADTNTIYTNCWVTGWGYTKERGETQNILQKATIPLVPNEECQKKYRDYVITKQ MICAGYKEGGIDACKGDSGGPLVCKHSGRWQLVGITSWGEGCARKEQPGVYTKVAEYIDWILEKIQSSKE RALETSPA 59/151 Rat plasma kallikrein mRNA (ACCESSION: NM_012725) >gill62138904|refINM_012725.21 Rattus norvegicus kallikrein B, plasma 1 (Klkbl), mRNA TGAAGACTAGCTTCATGTGAAGACTCCTTCTCCTCCAGCAGCACAAAGCAACCATCCTTCCAGGATGATT 5 TTATTCAAACAAGTGGGTTATTTTGTTTCCTTGTTCGCTACAGTTTCCTGTGGGTGTCTGTCACAACTGT ATGCAAATACCTTCTTCAGAGGTGGGGATCTGGCTGCCATCTACACCCCGGATGCCCAGCACTGTCAGAA GATGTGCACGTTTCACCCCAGGTGCCTGCTCTTCAGCTTCCTTGCCGTGAGTCCAACCAAGGAGACAGAT AAAAGGTTTGGGTGCTTCATGAAAGAGAGCATTACAGGGACTTTGCCAAGAATACACCGGACAGGGGCCA TTTCTGGTCATTCTTTAAAACAGTGTGGCCATCAATTAAGTGCTTGCCACCAAGACATATACGAAGGACT 10 GGATATGAGAGGGTCCAACTTTAATATATCTAAGACCGACAGTATTGAAGAATGCCAGAAACTGTGCACA AATAATATTCACTGCCAATTTTTCACATATGCTACAAAAGCATTTCACAGACCAGAGTACAGGAAGAGTT GCCTGCTGAAGCGCAGTTCAAGTGGAACGCCCACCAGTATAAAGCCAGTGGACAACCTGGTGTCTGGATT CTCACTGAAGTCCTGTGCTCTCTCAGAGATCGGTTGCCCCATGGATATTTTCCAGCACTTTGCCTTTGCA GACCTGAATGTAAGCCATGTCGTCACCCCCGATGCCTTCGTGTGTCGCACCGTTTGCACCTTCCATCCCA 15 ACTGCCTCTTCTTCACATTCTACACGAATGAGTGGGAGACGGAATCACAGAGGAATGTTTGTTTTCTTAA GACATCTAAAAGTGGAAGACCAAGTCCCCCTATTATTCAAGAAAATGCTGTATCTGGATACAGTCTCTTC ACCTGCAGAAAAGCTCGCCCTGAACCCTGCCATTTCAAGATTTACTCTGGAGTTGCCTTCGAAGGGGAAG AACTGAACGCGACCTTCGTGCAGGGAGCAGATGCGTGCCAAGAGACTTGTACAAAGACCATCCGCTGTCA GTTTTTTACTTACTCATTGCTTCCCCAAGACTGCAAGGCAGAGGGGTGTAAATGTTCCTTAAGGTTATCC 20 ACGGATGGCTCTCCAACTAGGATCACCTATGAGGCACAGGGGAGCTCTGGTTATTCTCTGAGACTGTGTA AAGTTGTGGAGAGCTCTGACTGTACGACAAAAATAAATGCACGTATTGTGGGAGGAACAAACTCTTCTTT AGGAGAGTGGCCATGGCAGGTCAGCCTGCAAGTAAAGTTGGTTTCTCAGAATCATATGTGTGGAGGGTCC ATCATTGGACGCCAATGGATACTGACGGCTGCCCATTGCTTTGATGGGATTCCCTATCCAGACGTGTGGC GTATATATGGCGGGATTCTTAATCTGTCAGAGATTACAAACAAAACGCCTTTCTCAAGTATAAAGGAGCT 25 TATTATTCATCAGAAATACAAAATGTCAGAAGGCAGTTACGATATTGCCTTAATAAAGCTTCAGACACCG TTGAATTATACTGAATTCCAAAAACCAATATGCCTGCCTTCCAAAGCTGACACAAATACAATTTATACCA ACTGCTGGGTGACTGGATGGGGCTACACAAAGGAACGAGGTGAGACCCAAAATATTCTACAAAAGGCAAC TATTCCCTTGGTACCAAATGAAGAATGCCAGAAAAAATATAGAGATTATGTTATAACCAAGCAGATGATC TGTGCTGGCTACAAAGAAGGTGGAATAGATGCTTGTAAGGGAGATTCCGGTGGCCCCTTAGTTTGCAAAC 30 ATAGTGGAAGGTGGCAGTTGGTGGGTATCACCAGCTGGGGCGAAGGCTGTGCCCGCAAGGAGCAACCAGG AGTCTACACCAAAGTTGCTGAGTACATTGACTGGATATTGGAGAAGATACAGAGCAGCAAGGAAAGAGCT CTGGAGACATCTCCAGCATGAGGAGGCTGGGTACTGATGGGGAAGAGCCCAGCTGGCACCAGCTTTACCA CCTGCCCTCAAGTCCTACTAGAGCTCCAGAGTTCTCTTCTGCAAAATGTCGATAGTGGTGTCTACCTCGC ATCCTTACCATAGGATTAAAAGTCCAAATGTAGACACAGTTGCTAAAGACAGCGCCATGCTCAAGCGTGC 35 TTCCTGCCTTGAGCAACAGGAACGCCAATGAGAACTATCCAAAGATTACCAAGCCTGTTTGGAAATAAAA TGGTCAAAGGATTTTTATTAGGTAGTGAAATTAGGTAGTTGTCCTTGGAACCATTCTCATGTAACTGTTG ACTCTGGACCTCAGCAGATCACAGTTACCTTCTGTCCACTTCTGACATTTGTGTACTGGAACCTGATGCT GTTCTTCCACTTGGAGCAAAGAACTGAGAAACCTGGTTCTATCCATTGGGAAAAAGAGATCTTTGTAACA TTTCCTTTACAATAAAAAGATGTTCTACTTGGACTTGAAAAAAAAAAAAAAAAAAAAAAA 40 Modifications It is possible to modify polypeptides that inhibit kallikrein in a variety of ways. For example, the polypeptides can be attached to one or more polyethylene glycol 45 moieties to stabilize the compound or prolong retention times, e.g., by at least 2, 4, 5, 8, 10, 15, 20, 50, 100, 500 or 1000 fold. In one embodiment, a kallikrein binding protein is physically associated with a moiety that improves its stabilization and/or retention in circulation, e.g., in blood, serum, 60/151 lymph, or other tissues, e.g., by at least 1.5, 2, 5, 10, or 50 fold. For example, a kallikrein binding protein can be associated with a polymer, e.g., a substantially non-antigenic polymer, such as a polyalkylene oxide or polyethylene oxide. Suitable polymers will vary substantially by weight. Polymers having molecular number average weights 5 ranging from about 200 to about 35,000 (or about 1,000 to about 15,000, and 2,000 to about 12,500) can be used. For example, a kallikrein binding protein can be conjugated to a water soluble polymer, e.g., hydrophilic polyvinyl polymers, e.g. polyvinylalcohol and polyvinylpyrrolidone. A plurality of polymer moieties can be attached to one polypeptide, e.g., at least two, three, or four such moieties, e.g., having an average 10 molecular weight of about 2,000 to 7,000 Daltons. A non-limiting list of such polymers include polyalkylene oxide homopolymers such as polyethylene glycol (PEG) or polypropylene glycols, polyoxyethylenated polyols, copolymers thereof and block copolymers thereof, provided that the water solubility of the block copolymers is maintained. 15 For example, the polypeptide can be conjugated to a water soluble polymer, e.g., a hydrophilic polyvinyl polymer, e.g. polyvinylalcohol and polyvinylpyrrolidone. A non limiting list of such polymers include polyalkylene oxide homopolymers such as polyethylene glycol (PEG) or polypropylene glycols, polyoxyethylenated polyols, copolymers thereof and block copolymers thereof, provided that the water solubility of 20 the block copolymers is maintained. Additional useful polymers include polyoxyalkylenes such as polyoxyethylene, polyoxypropylene, and block copolymers of polyoxyethylene and polyoxypropylene (Pluronics); polymethacrylates; carbomers; branched or unbranched polysaccharides which comprise the saccharide monomers D mannose, D- and L-galactose, fucose, fructose, D-xylose, L-arabinose, D-glucuronic acid, 25 sialic acid, D-galacturonic acid, D-mannuronic acid (e.g. polymannuronic acid, or alginic acid), D-glucosamine, D-galactosamine, D-glucose and neuraminic acid including homopolysaccharides and heteropolysaccharides such as lactose, amylopectin, starch, hydroxyethyl starch, amylose, dextrane sulfate, dextran, dextrins, glycogen, or the polysaccharide subunit of acid mucopolysaccharides, e.g. hyaluronic acid; polymers of 30 sugar alcohols such as polysorbitol and polymannitol; heparin or heparan. 61/151 Other compounds can also be attached to the same polymer, e.g., a cytotoxin, a label, or another targeting agent or an unrelated agent. Mono-activated, alkoxy terminated polyalkylene oxides (PAO's), e.g., monomethoxy-terminated polyethylene glycols (mPEG's); C 14 alkyl-terminated polymers; and bis-activated polyethylene oxides 5 (glycols) can be used for crosslinking. See, e.g., U.S. 5,951,974. A kallikrein inding protein can also be associated with a carrier protein, e.g., a serum albumin, such as a human serum albumin. For example, a translational fusion can be used to associate the carrier protein with the kallikrein binding protein. Methods 10 Provided herein are methods and compositions for treating and/or preventing mucositis by administering an isolated inhibitor of kallikrein to a subject having, or suspected of having, or at risk of having, mucositis. A subject (e.g., patient) who is at risk for developing mucositis can be, e.g., a subject who will be undergoing, is undergoing, or will be undergoing a chemotherapy (e.g., high-dose chemotherapy) and/or 15 radiotherapy regimen. As another example, a subject (e.g., patient) who is at risk for developing mucositis can be, e.g., a subject who has been diagnosed with cancer, e.g., cancer of the head or neck. The methods can be practiced in humans in need of treatment for mucositis or in nonhuman subjects. 20 In one embodiment, a method for treatment includes administration of an isolated polypeptide comprising a Kunitz domain as the inhibitor of kallikrein. One embodiment of the method uses a polypeptide containing an amino acid sequence of SEQ ID NO: 1 that has an affinity for kallikrein that is approximately 30-fold or more higher than that of a broad range serine protease, e.g., aprotinin, which is isolated from bovine lung and 25 currently approved for use in coronary artery bypass grafting procedures (TRASYLOLTM, Bayer Corporation Pharmaceutical Division, West Haven, Conn.). Administration of an isolated kallikrein inhibitor results in improvement of, a reduction in the severity of, the prevention of, or the stabilization of at least one symptom of mucositis, such as pain, edema, erythema, secondary bacterial colonization, or 62/151 limitation of food consumption. The success and/or progress of such methods for treating or preventing mucositis may be evaluated by any one of the following parameters: - Reduction in the frequency of development of mucositis (or) - Reduction in the duration of mucositis at any given level of disease 5 severity (or) - Reduction in the severity (grades 1-4) of development of mucositis at any time course during treatment (or) - Reduction in any of the associated signs or symptoms of mucositis, including but not limited to: 10 o Pain o Edema o Erythema o Secondary bacterial colonization o Limitation of food consumption (solid, liquid) 15 o Fatigue o Ability to tolerate higher or repeat doses of chemotherapy or radiation therapy in the aggregate treated population compared to aggregate non treated patient populations 20 Combination Therapy The isolated kallikrein inhibitor may be administered along with another therapeutic as part of a combination therapy for mucositis. The other therapeutic may be a supportive therapy, or a therapeutic agent, such as palifermin (KEPIVANCE@) (human keratinocyte growth factor (KGF)). Supportive treatments include sucking on ice cubes, 25 antioxidants, and mouth rinses (e.g., GELCLAIR@, CAPHOSOL@, MUGARD@). Several mouth rinses are available that combine antihistamines, anesthetics, anti inflammatory medications (such as corticosteroids), antibiotics, and antifungals. Narcotic analgesics may also prove to help relieve the pain. Other supportive treatments include antimicrobials, anti-inflammatories, and good oral care. 30 Combination therapy with a kallikrein inhibitor and another therapeutic agent may be provided in multiple different configurations. In situations where the kallikrein 63/151 inhibitor is to be administered by intraarticular injection, the kallikrein inhibitor and the therapeutic agent may be co-administered as a single composition, or they may be administered by separate injections. In some situations, the kallikrein inhibitor and the therapeutic agent are administered in close temporal proximity (e.g., a short time interval 5 between the injections, such as during the same treatment session), or more widely spaced, depending on the desired schedule of administration for the two components of the combination therapy. When the kallikrein inhibitor is to be administered by systemic (parenteral) administration, the kallikrein inhibitor and the therapeutic agent may be administered in close temporal proximity or more widely spaced, depending on the 10 intended dosing schedule for the two components of the combination therapy. Administration The kallikrein inhibitor (alone or as part of a combination therapy) can be administered to a patient before, during, and/or after the onset clinical symptoms of 15 mucositis. The patient is generally a human, but may also be a non-human mammal. Human patients include adults, e.g., patients between ages 19-25, 26-40, 41-55, 56-75, and 76 and older, and pediatric patients, e.g., patients between ages 0-2, 3-6, 7-12, and 13-18. The term "pharmaceutically acceptable" composition refers to a non-toxic carrier 20 or excipient that may be administered to a patient, together with a kallikrein inhibitor described herein. The carrier or excipient is chosen to be compatible with the biological or pharmacological activity of the composition. The kallikrein inhibitors (and, in the case of combination therapy, other therapeutic agent) described herein can be administered locally or systemically by any suitable means for delivery of an inhibitory amount of the 25 inhibitor and/or other therapeutic agent to a patient including but not limited to systemic administrations such as, for example, intravenous and inhalation. Parenteral administration is particularly preferred for the kallikrein inhibitor. For parenteral administration, the kallikrein inhibitor can be injected intravenously, intramuscularly, intraperitoneally, or subcutaneously. Subcutaneous 64/151 injection and i.v. administration are preferred routes for parenteral administration. Also useful is local (intraarticular) injection. Typically, compositions for administration by injection are solutions in sterile isotonic aqueous buffer (e.g., sodium/potassium phosphate buffered saline). Other 5 pharmaceutically acceptable carriers include, but are not limited to, sterile water, saline solution, and buffered saline (including buffers like phosphate or acetate), alcohol, vegetable oils, polyethylene glycols, gelatin, lactose, amylose, magnesium stearate, talc, silicic acid, paraffin, etc. Where necessary, the composition can also include a solubilizing agent and a local anesthetic such as lidocaine to ease pain at the site of the 10 injection, preservatives, stabilizers, wetting agents, emulsifiers, salts, lubricants, etc. as long as they do not react deleteriously with the active compounds. Similarly, the composition can comprise conventional excipients, e.g., pharmaceutically acceptable organic or inorganic carrier substances suitable for parenteral, enteral or intranasal application which do not deleteriously react with the active compounds. Generally, the 15 ingredients will be supplied either separately or mixed together in unit dosage form, for example, as a dry lyophilized powder or water free concentrate in a hermetically sealed container such as an ampoule, sachette, or vial indicating the quantity of active agent in activity units. Where the composition is to be administered by infusion, it can be dispensed with an infusion bottle containing sterile pharmaceutical grade "water for 20 injection" or saline. Where the composition is to be administered by injection, a container (e.g., ampoule or vial) of sterile water for injection or saline can be provided so that the ingredients can be mixed prior to administration. Exemplary formulations for subcutaneous administration of an isolated kallikrein inhibitor include buffered solutions containing a buffering agent (e.g., histidine or 25 phosphate buffer) and a cryoprotectant (e.g., sucrose or sucrose and mannitol, optionally including a dextran such as dextran 40), and may be lyophilized for storage and distribution as described in U.S. Pub. App. No. 2007-0213275 (U.S. Serial No. 11/716,278, filed March 9, 2007). In one embodiment, the kallikrein inhibitor is administered to a patient as an 30 intravenous infusion according to any approved procedure. In another embodiment, the kallikrein inhibitor is administered to a patient as a subcutaneous bolus. In another 65/151 embodiment, the kallikrein inhibitor is administered to a patient by intraarticular injection. I.V. and intraarticular administration are typically carried out by a health care professional in a clinical setting (e.g., hospital, urgent care, or doctor's office), but subcutaneous injections may be self-administered or administered by a health care 5 professional. Parameters that can be evaluated for determining a dose of the kallikrein inhibitor for systemic administration, are described below with regards to DX-88 (a non-naturally occurring kallikrein inhibitor, SEQ ID NO:2). The total amount of circulating prekallikrein in plasma is reported to be approximately 500 nM to 600 nM (Silverberg et 10 al., "The Contact System and Its Disorders," in Blood: Principles and Practice of Hematology, Handin, R. et al., eds, J B Lippincott Co., Philadelphia, 1995). If all prekallikrein is activated, about 520 nmoles/L of DX-88 (DX88) can be used to inhibit kallikrein in a stoichiometric manner. An individual having 5 L of plasma would require a dose of 2.6 micromoles DX-88, or approximately 18 mg based on the molecular weight 15 of DX-88 of 7,054 Daltons. This was calculated as follows: the Ki of DX88 is 0.044 nM. When it is desired to have a concentration of plasma kallikrein (PK) of, e.g., lnM, the formula Ki= 0.044nM =[DX88] x [PK]/[DX88-PK] = [DX88] x 1 nm/499 nM, indicates that the concentration of free DX-88 is 22.0 nM. Thus, the total amount of DX-88 needed would be 499 + 22 or 521 nM. The dose can be reduced proportionally if not all 20 of the prekallikrein is activated or if a portion of the kallikrein is deactivated by an endogenous inhibitor, e.g., C1 esterase inhibitor (C1INH). Thus, in certain embodiments, about 5, 10, 15, 20, 30, 40, 60,80, 120, 250, 500, 600, 700, 800, 1000 mg of DX-88 can be administered to a subject, in a single dose or in one or more doses spread over a twenty-four hour period. Consideration of several other factors may provide a more 25 accurate estimation of the dose of DX-88 required in practice, such as patient age, weight, and severity of the mucositis and associated symptoms. In some embodiments, the kallikrein inhibitor polypeptide is administered in a dose of about 1-500 mg/m 2 , preferably about 1-250 mg/m 2 , 1-100 mg/m 2 . 66/151 Devices and Kits Pharmaceutical compositions that include the kallikrein inhibitor can be administered with a medical device. The device can designed with features such as portability, room temperature storage, and ease of use so that it can be used in settings 5 outside of a hospital or emergency room/urgent care facility (e.g., by the patient or a caregiver in the home or in a doctor's office). The device can include, e.g., one or more housings for storing pharmaceutical preparations that include an isolated kallikrein inhibitor, and can be configured to deliver one or more unit doses of the agent or agents. I.V. administration may be by bolus or infusion, using appropriate injection or 10 infusion devices (e.g., catheters, infusion pumps, implants, and the like). Subcutaneous injection may be as an infusion, for example using a catheter and infusion pump or implantable device. Many other devices, implants, delivery systems, and modules are also known. When the kallikrein inhibitor is distributed as a lyophilized powder, it must be 15 reconstituted prior to use. Manual reconstitution (e.g., manual addition of diluent to the lyophilized formulation by injection through an injection port into the container containing the lyophilized formulation) may be used, or the kallikrein inhibitor may be provided in a device configured for automatic reconstitution (e.g., automatic addition of the diluent to the lyophilized formulation), such as the BECTON-DICKINSON BDTM 20 Liquid Dry Injector. The isolated kallikrein inhibitor can be provided in a kit. In one embodiment, the kit includes (a) a container that contains a composition that includes an isolated kallikrein inhibitor, and (b) informational material that relates to the methods described herein and/or the use of the agents for therapeutic benefit. 25 In certain embodiments, the kit includes also includes another therapeutic agent. For example, the kit includes a first container that contains a composition that includes the isolated kallikrein inhibitor, and a second container that includes the other therapeutic agent. The isolated kallikrein inhibitor and the other therapeutic agent may be supplied in the same container for use in methods in which the kallikrein inhibitor and the therapeutic 30 agent are administered as a single composition. 67/151 The informational material of the kits is not limited in its form. In one embodiment, the informational material can include information about production of the compound, molecular weight of the compound, concentration, date of expiration, batch or production site information, and so forth. In one embodiment, the informational material 5 relates to methods of administering the isolated kallikrein inhibitor, e.g., in a suitable dose, dosage form, or mode of administration (e.g., a dose, dosage form, or mode of administration described herein), to treat a subject who has mucositis. The information can be provided in a variety of formats, include printed text, computer readable material, video recording, or audio recording, or a information that provides a link or address to 10 substantive material. In addition to the isolated kallikrein inhibitor (and, if present, the additional therapeutic agent(s)), the composition in the kit can include other ingredients, such as a solvent or buffer, a stabilizer, or a preservative. The isolated kallikrein inhibitor (and other therapeutic agent, if present) can be provided in any form, e.g., liquid, dried or 15 lyophilized form, preferably substantially pure and/or sterile. When the agents are provided in a liquid solution, the liquid solution preferably is an aqueous solution. When the agents are provided as a dried form, reconstitution generally is by the addition of a suitable solvent. The solvent, e.g., sterile water or buffer, can optionally be provided in the kit. 20 The kit can include one or more containers for the composition or compositions containing the agents. In some embodiments, the kit contains separate containers, dividers or compartments for the composition and informational material. For example, the composition can be contained in a bottle, vial, or syringe, and the informational material can be contained in a plastic sleeve or packet. In other embodiments, the 25 separate elements of the kit are contained within a single, undivided container. For example, the composition is contained in a bottle, vial or syringe that has attached thereto the informational material in the form of a label. In some embodiments, the kit includes a plurality (e.g., a pack) of individual containers, each containing one or more unit dosage forms (e.g., a dosage form described herein) of the agents. The containers can include a 30 combination unit dosage, e.g., a unit that includes both the isolated kallikrein inhibitor and another therapeutic agent, e.g., in a desired ratio. For example, the kit includes a 68/151 plurality of syringes, ampoules, foil packets, blister packs, or medical devices, e.g., each containing a single combination unit dose. The containers of the kits can be air tight, waterproof (e.g., impermeable to changes in moisture or evaporation), and/or light-tight. The kit optionally includes a device suitable for administration of the 5 composition, e.g., a syringe or other suitable delivery device. The device can be provided pre-loaded with one or both of the agents or can be empty, but suitable for loading. EXEMPLIFICATION The following examples provide further illustration and are not limiting. 10 Prophetic Example 1: Determination of the Efficacy of DX-88 for the Prevention and Treatment of Oral Mucositis The primary objective of this preclinical development plan is to establish the efficacy of an optimal formulation and schedule of DX-88 (and/or related compounds) as 15 an intervention for oral mucositis induced by chemotherapy or radiation therapy used for the treatment of cancer. The plan consists of a series of logically sequenced experiments to be performed in a validated and predictive animal model (described below) of the condition: Efficacy screening (Step 1). Acute radiation-induced mucositis is used to screen 20 compounds and formulations. In this model, animals receive a single large dose of radiation directed to isolated cheek mucosa. The kinetics and extent of ulcerative mucositis that develops follows a consistent course. Attenuation of ulcerative mucositis is a robust endpoint that will be used to define DX-88 efficacy. Using this model, subcutaneous, intraperitoneal and topical formulations of DX-88 will be evaluated in a 25 dose-ranging format. Dose-ranging optimization and schedule screen (Step 2). The lead formulation established in Step 1 will be evaluated using additional doses applied at varied scheduling schemes (i.e. pre-radiation and continuing for 7 days, post-radiation and daily for 14 days, etc). 69/151 CLINICAL DECISION POINT: Determination of product target population (cycled chemotherapy, radiation therapy, HSCT). Subsequent pre-clinical testing modeled around anticipated product claims/market priorities. Dose scheduling determination (Step 3). If radiation therapy-induced mucositis is 5 the lead indication, scheduling studies will be performed in a fractionated radiation model, which mimics the dosing schedule in humans. If, on the other hand, cycled chemotherapy is selected as the primary indication, a chemotherapy (likely 5 fluorouracil) model will be used. A smaller version of this study, focusing on the optimal protocol, may be done to confirm the observations of the original study. 10 Note: A requirement of any supportive oncology product is that it its protection of normal tissue does not modify tumor response to cytotoxic therapy. Consequently, in parallel, studies will be performed to demonstrate the inertia of DX-88 as a modifier of tumor growth or response to therapy. Study 1. Mucositis Acute Radiation. This will be a dose-ranging study 15 comparing 2-3 formulations. This will be a 30 day study with 8 groups (64 animals). The dosing will be done from day -I to day 20. If we observe efficacy in one or more treatment groups, we will be able to move directly to an optimization study. If there is no efficacy, we may have to repeat the study with increased dosing or altered formulations. Study 2. Mucositis Acute Radiation. This will be a dose-ranging study of the 20 optimal formulation. In this study we will extend dose ranging and examine alternate dosing schedules. This will be a 30 day study with 8 groups (64 animals). If both studies go well and we determine an optimal dose/schedule protocol, we will move to a modified study to address specific clinical populations. It is possible that all questions of dose and schedule may not be answered in the first 2 studies. In that case, a third study 25 may be necessary. Study 3. Mucositis Acute Radiation (Necessity dependent on results of Studies 1 + 2). Any ambiguous questions about optimal dose, formulation and/or schedule remaining after the first 2 studies will be addressed in this experiment. This will be a 30 day study with 8 groups (64 animals). This study may be larger or smaller depending on 30 the questions that remain to be answered. 70/151 Study 4. Mucositis Study targeted to a clinical population. This study will be either a fractionated radiation study or a combination chemotherapy/radiation study depending on Dyax's development priority. This study objective will be to determine optimal dose and schedule for the specified clinical indication. In this study we will 5 bracket the optimal doses and schedules to obtain best fit. A chemo/radiation study would take 40 days and evaluate 7 experimental groups (70 animals). The fractionated radiation study would also take 40 days to complete, would be of similar size. Study 5. Mucositis Study targeted to a clinical population. This study will be a confirmatory study of Study 4. This study objective will be to confirm the optimal dose 10 and schedule for the specified clinical indication. In this study we will bracket the optimal doses and schedules to obtain best fit. This study will be smaller than study 4 and will be priced according to the number on animals involved. Prophetic Example 2: Determination of the Efficacy of Epi-KAL2 for the Prevention and 15 Treatment of Oral Mucositis Study Objective The objective of this study is to demonstrate efficacy for EPI-KAL2 on the frequency, severity and duration of oral mucositis induced by acute radiation. EPI-KAL2 is potent (Ki,app = 0.1 nM) active site inhibitor of pKal and a Kunitz domain inhibitor 20 based on the first domain of tissue factor pathway inhibitor (Markland (1996) Iterative optimization of high-affinity protease inhibitors using phage display. 2. Plasma kallikrein and thrombin.Biochemistry. 35(24):8058-67). The sequence of EPI-KAL2 is: EAMHSFCAFKADDGPCRAAHPRWFFNIFTRQCEEFSYGGCGGNQNRFESL 25 EECKKMCTRD (amino acids in italics are those that differ from TFPI) In this initial study, 2 routes of administration will be studied. The primary goal of this study is to obtain a signal for efficacy for each route of administration. The results 30 of this study will provide the basis for future optimization of both dose and schedule in the treatment of oral mucositis. 71/151 Materials and Methods Table 2: Test System Species/strain: Golden Syrian Hamster Physiological state: Normal Age/weight range at start of study: Animals aged 5 to 6 weeks with body weight of approximately 80 g Animal supplier: Charles River Laboratories Number/sex of animals: 24/ male Identification: Animals will be individually numbered using an ear punch. A cage card or label with the appropriate information necessary to identify the study, dose, animal number and treatment group will mark all cages. Randomization: Animals will be randomly and prospectively divided into 3 groups of 8 animals each prior to treatment or irradiation. Justification: The acute radiation model in hamsters has proven to be an accurate, efficient and cost effective technique to provide a preliminary evaluation of anti-mucositis compounds. The model is also useful in studying specific mechanistic elements in the pathogenesis of mucositis and its prevention. Replacement: Animals will not be replaced during the course of the study. Table 3: Test Article Identification (Lot Number) EPI-KAL2 (Lot 100808) Physical Description Frozen liquid 72/151 Formulation Phosphate buffered saline, pH 7.0 Storage Conditions Nominally -20'C Concentration 5.6 mg/mL Stability Stable for 24 hours at 2-4'C Disposition of unused dosing mixture: Unused, frozen test article will be returned to Sponsor. Empty and partially used vials of dosing preparations will be discarded according to proper disposal procedures. Table 4: Administration of Test Article Route and method of administration: Topically to left cheek pouch or IP Justification for route of administration: Topical and IP routes of exposure were selected because they represent potential routes of human exposure Frequency and duration of dosing: Animals will be dosed by both routes of administration on Days -1 to 20. Topical administration will be twice daily (BID) and IP administration will be once daily (QD). Administered doses: 20 mg/kg/day Administered volume(s): To be calculated based on pre-dosing body weight Justification for dose levels: The dose levels represent the upper dose range and were selected in an attempt to maximize potential efficacy Experimental Design Twenty four (24) male Syrian Golden Hamsters will be given an acute radiation 5 dose of 40 Gy directed to their left buccal cheek pouch on Day 0. This will be accomplished by anesthetizing the animals and everting the left buccal pouch, while protecting the rest of the animals with a lead shield. Test materials will be given by 73/151 topical administration directed to the left cheek pouch, or IP injection. Mucositis will be evaluated clinically starting on Day 6, and continuing on alternate days until Day 28. On Day 28, all animals will be euthanized by C02 inhalation and death will be confirmed by monitoring heartbeat in accordance with USDA guidelines. At necropsy, 5 left and right cheek pouches will be harvested and snap frozen in liquid nitrogen. These samples will be stored at -80 0 C and shipped on dry ice for Biomarker analysis. Table 5. Study Design Group Number of Treatment Route of Treatment Volume Number Animals Administration Schedule* (mL) 1 8 males No Treatment None N/A 2 8 males EPI-KAL2 topical DaysBased on 20 mg/kg, bid weight EPI-KL2 IPBased on 3 8 males EPI-KAL2 Days -1 to 20 20 mg/kg, qd weight 10 Experimental Procedures Mucositis Induction Mucositis will be induced using a single dose of radiation (40 Gy/dose) administered to all animals on Day 0. Radiation will be generated with a 160 kilovolt potential (15-ma) source at a focal distance of 21 cm, hardened with a 3.0 mm Al 15 filtration system. Irradiation will target the left buccal pouch mucosa at a rate of 2.5 Gy/minute. Prior to irradiation, animals will be anesthetized with an intraperitoneal 74/151 injection of ketamine (160 mg/kg) and xylazine (8 mg/kg). The left buccal pouch will be everted, fixed and isolated using a lead shield. Mucositis Scoring Starting on Day 6 and continuing every second day thereafter (Days 8, 10, 12, 14, 5 16, 18, 20, 22, 24, 26, & 28), each animal will be photographed and evaluated for mucositis scoring. Parameters to be measured include the mucositis score, weight change and survival. For the evaluation of mucositis, the animals will be anesthetized with inhalation anesthetics, and the left pouch everted. Mucositis will be scored visually by comparison to a validated photographic scale, ranging from 0 for normal, to 5 for severe 10 ulceration (clinical scoring). In descriptive terms, this scale is defined as follows: Score: Description: 0 Pouch completely healthy. No erythema or vasodilation. 1 Light to severe erythema and vasodilation. No erosion of mucosa. 2 Severe erythema and vasodilation. Erosion of superficial aspects of 15 mucosa leaving denuded areas. Decreased stippling of mucosa. 3 Formation of off-white ulcers in one or more places. Ulcers may have a yellow/gray appearance due to pseudomembrane. Cumulative size of ulcers should equal about of the pouch. Severe erythema and vasodilation. 4 Cumulative size of ulcers should equal about of the pouch. Loss of 20 pliability. Severe erythema and vasodilation. 5 Virtually all of pouch is ulcerated. Loss of pliability (pouch can only partially be extracted from mouth) A score of 1-2 is considered to represent a mild stage of the disease, whereas a score of 3-5 is considered to indicate moderate to severe mucositis. Following this 25 preliminary clinical scoring, a photograph will be taken of each animal's mucosa using a standardized technique. At the conclusion of the experiment, film will be developed and the photographs randomly numbered for blinded scoring. Thereafter, two independent, trained observers will grade the photographs in blinded fashion using the above-described scale. For each photograph the actual blinded score will be based upon the average of the 30 evaluator's scores. Only the scores from this blinded, photographic evaluation will be statistically analyzed and reported in the final study report. 75/151 Mucositis Evaluation Using the blinded photographs, the grade of mucositis will be scored, beginning Day 6, and for every second day thereafter, through and including Day 28. The effect on mucositis of each drug treatment compared to vehicle control will be assessed according 5 to the following parameters: The difference in the number of days hamsters in each group have severe (score 3) mucositis. On each day the animals are scored (evaluation day), the number of animals with a blinded mucositis score of 3 in each drug treatment group will be compared to the 10 vehicle control group. Differences will be analyzed on a daily as well as a cumulative basis. Treatment success will be considered if a statistically significant lower number of hamsters with a score of >3 in a drug treatment group, versus control as determined by chi-square analysis. The rank sum differences in daily mucositis scores. 15 For each evaluation day the scores of the vehicle control group will be compared to those of the treated groups using the non-parametric rank sum analysis. Treatment success will be considered as a statistically significant lowering of scores in the treated group on 2 or more days from day 6 to day 28. To evaluate the effect of test agents on mucositis resolution, the time to healing 20 will be compared between test and controls. Resolution will be defined as the absence of ulcerative lesions (scores <3). Body Weight Every day for the period of the study, each animal will be weighed and its survival recorded, in order to assess possible differences in animal weight among 25 treatment groups as an indication for mucositis severity and/or possible toxicity resulting from the treatments. Animals Found Dead or Moribund Animal deaths in this model generally occur as a consequence of anesthesia overdose or drug toxicity. Animals will be monitored on a daily basis and those 30 exhibiting weight loss greater than 20% will be euthanized. Any adverse effects or unanticipated deaths will be reported immediately. 76/151 Data Analysis and Reporting Statistical Analysis Statistical differences between treatment groups will be determined using Student's t-test, Mann-Whitney U test and chi-square analysis with a critical value of 0.05. It is anticipated that up to 10 % animal death may occur, primarily 5 as a result of the administration of anesthetics. However, the number of animals expected to remain alive at Day 28 (6 per treatment group) is considered acceptable for statistical evaluation. Example 3: Inhibitory Anti-Plasma Kallikrein Binding Proteins 10 We have discovered several antibody inhibitors and binders of plasma kallikrein (pKal). The most potent of these have been further characterized and shown to have apparent inhibition constants (Ki,app) < 10 nM, to be specific pKal inhibitors with respect to other tested serine proteases, and to not bind prekallikrein. Amino acid sequences of the CDRs for the inhibitors are shown in Table 6. 77/151 22 2 2 F.T N - ~ U U U > U U U U U U~ >-1 D D U U > >- U - D - 2 D ~ 2 >- U en H CD M U 2 2 ~2 m U 2 D U DU > A Z K H U >D U H U U rA > m U U o U H K H U Q m U o H - U U U U U | |D | |- | |D | | -. K K K K K K Ko K K LK K U D o H U a2 a N N N2 N U T N U U U U U U U U U U U U U U ~ U U U U U U U U U 78/151 0 K 0 0 K 0 0 CD 0 0 U K K K K K K ~ K 0 K ~2 K K K 0 0 0 0 0 U K 0 ~ 3 0 K ~2 K K 0 Q< 0 K K K U K U ~ Q< U ~2 ~ K K K ~2 m r< U U m r< 0 m m m U m 0 K Q< Z K U K Q< K Q< K Q< ~ m r< K K r< m ~ m U K m U m m ~ m ~2 m m m U m m m ~ K Q< K m ~2 m ~ m m m ~ 0 ~ ~ K m :< U m U ~; m U K U ~ m m ~q m m 0 K ~ Z K m r< U U U :< U ~2 Q< U U U 0 U 0 U U U 0 Q< U U U U U U U U U U U U U U U U U U U z z z z z z z z z z z z z z z m m m m m m m m m m m m m m m m 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 K K K K K K K K K K K K K K K K ~2 ~2 K Z ~ m K 3 ~ K K K K K K K K K K K K K K K K K K K m m ~ m m m ~ m ~ m m m U U U U U U U U U U U U U U U U U U U U U U U U U U U U U U U U m m m m m m m m m m m m m m m m m m m m K m ~ m ~ r< m K m U m m K Q< m m U U ~ K ~ m m U K m U K K K m K T 0 3 m m T U K Z ~2 ~2 ~2 ~2 ~2 ~2 ~2 ~2 ~2 ~2 ~2 ~2 ~2 ~2 ~2 ~2 m m m ~ m m m m K K K K K K K K K K K K K K K K K 0 ~2 K T 0 T K K K U K U Q< K K K ~ K K K ~ K Q< ~ K K K K K K ~ m ~ K m ~ K K m K ~ m 0 T 0 K ~ m ~ m m m K K K K 0 0 K ~ 0 K m 0 K 0 ~ K K K ~ U ~ m m ~ U m ~ ~ K m m m a a ~2 3 3 ~2 3 3 3 ~2 3 3 3 3 C~ m ~2 ~ C~ C~ C~ ~2 C~ C~ C~ C~ C~ C~ C~ m m m m m m K m m m m m m m m m a ~2 3 3 3 3 3 3 m m m m m ~ m m ~ m ~ Q< K K Q< Z K m K Z K Q< ~ m m m m m m m m K m m m m 0 0 ~ m 0 ~2 0 ~2 0 ~2 3 ~ K ~ m ~2 0 3 0 ~2 ~2 3 z 0 0 ~ ~ K m K ~ K ~ K K ~ m K ~ U K ~ ~2 m U m ~ m ~ K ~ U ~ ~ K ~ K m 0 m m K K K ~2 K K K ~ K K K z U 0 T U ~ m z ~ m m z m ~ 0 m ~ 0 m 0 U m m 0 m 0 0 0 U ~ ~ U U ~q m m m m m ~q o m U ~q m z m 3 ~q ~ 3 3 z U 3 3 z 3 3 3 3 0 m m m ~ m m 0 m m m 0 m m m m u u m m m mm m m m m ~2 ~2 ~2 V V V 0> o o o 0> ~ U ~ 0 0 0 0 o ~ 0 ~T (N 0 00 V V V V 0 (N 0> 0 KS C~ 00 ~m * * * * * * * * ~D ~D ~D 00 0> 0 0> KS 0> cc (N (N (N (N 00 (N (N (N KS 0 0 0 C~ C~ 0> o o C) 0 0 ~2 U C) ~ 0 0 0 0 0 ~ C) C) 0 > (N KS (N 0 (N C~ KS KS KS KS > > > ~m > > KS KS KS 79/151 0 0 0 0 0 * H H H H H H m H 0 H K H2 H H2 x x x x x x Q o e o e o e u e S CD D CD CD CD 1 oD oD oD oD oD oD o a H H H H H H K K K K K - _ aK a a a C . m o o o o o om m mm -a r a S x x x x x) 80/15 Amino acid sequences of light chain (LC) and heavy chain (HC) variable domain of pKal antibody inhibitors are shown below. M6-DO9 LC QDIQMTQSPS SLSASVGDRV TITCRASQSI RNYLNWYQQK PGKAPNLLIY AASTLQSGVP 60 5 ARFSGSGSGT DFTLTISSLQ PEDFATYYCQ QLSGYPHTFG QGTKLEIK 108 M6-DO9 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS FYYMVWVRQA PGKGLEWVSV IYPSGGITVY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARDK WAVMPPYYYY AMDVWGQGTT 120 10 VTVSSASTKG PSVFPLAPSS KS 142 M7-B04 LC QSALTQPASV SGSPGQSITI SCTGTNSDVG NYNLVSWYQQ HPGEAPKLLI YEVNKRPSGV 60 SNRFSGSKSG NTASLTISGL QAEDEADYLC CSYAGNRNFY VFGAGTKVTV L 111 15 M7-B04 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS WYSMVWVRQA PGKGLEWVSS ISPSGGLTNY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARHT AARPFYYYYM DVWGKGTTVT 120 VSSASTKGPS VFPLAPSSKS 140 20 M7-E07 LC QSELTQPPSV SVSPGQTASI TCSGDKLGDK YACWYQQKPG QSPVLVIYQD SKRPSGIPER 60 FSGSNSGNTA TLTISGTQAM DEADYYCQAW DSSTGVFGGG TKLTVL 106 25 M7-E07 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS WYLMIWVRQA PGKGLEWVSY IYPSGGFTYY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED MAVYYCARTE GPLSWGYGMD VWGQGTTVTV 120 SSASTKGPSV FPLAPSSKS 139 30 M8-A09 LC QCELTQPPSE SVSPGQTANI TCSGDKLGNK YAYWYQQKPG QSPVLVIYQD NNRPSGIPER 60 FSGSNSGNTA TLTISGTQAI DEANYYCQAW DSRTVVFGGG TKLTVL 106 M8-A09 HC 35 EVQLLESGGG LVQPGGSLRL SCAASGFTFS TYFMLWVRQA PGKGLEWVSS IYPSGGNTVY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARAA SPVRNYYYYG MDVWGQGTTV 120 TVSSASTKGP SVFPLAPSSK S 141 M10-F1O LC 40 QDIQMTQSPS SLSASVGDRV TITCRASQSI SVYLNWYQHK PGKAPKLLIY GASNLQFGVP 60 SRFSGSGYGT DFTLTISSLQ PEDFATYHCQ QTFSLFTFGG GTKVEIK 107 M10-F1O HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS FYNMNWVRQA PGKGLEWVSS ISPSGGETNY 60 45 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARGG GAYRNNWWGG FDIWGLGTMV 120 TVSSASTKGP SVFPLAPSSK S 141 M10-H05 LC QDIQMTQSPG TLSLSPGERA TLSCRASQSV SSSYLAWYQQ KPGQAPRLLI YGASSRATGI 60 50 PDRFSGSGSG TDFTLTISRL EPEDFAVYYC QQYGSSPFTF GPGTKVDIK 109 M10-H05 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS PYNMYWVRQA PGKGLEWVSS IRPSGGGTVY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCAGGF IAARWYYFDY WGQGTLVTVS 120 55 SASTKGPSVF PLAPSSKS 138 81/151 M12-B05 LC QSALTQPPTV SVSPGQTARI TCSGNKLGDK YVAWYQQKPG QSPMLVIYQD TKRPSRVSER 60 FSGSNSANTA TLSISGTQAL DEADYYCQAW DSSIVIFGGG TRLTVL 106 5 M12-B05 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS WYTMVWVRQA PGKGLEWVSY IYPSGGATFY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCAMGS YDYIWGFYSD HWGQGTLVTV 120 SSASTKGPSV FPLAPSSKS 139 10 M12-DO5 LC QSVLTQPPSV SVSPGQTATI TCSGDQLGDK YVGWYQQKPG QSPILVIYQD TKRPSGIPER 60 FSGSNSGNTA TLTISGTHTV DEAHYYCQAW DTSTAGFGGG TKLTVL 106 15 M12-DO5 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS WYTMVWVRQA PGKGLEWVSR IYPSGGWTKY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TATYYCAREG LLWFGENAFD IWGQGTMVTV 120 SSASTKGPSV FPLAPSSKS 139 20 M27-EQ5 LC QSELTQPPSV SVSPGQTASI TCSGDKLGDK YACWYQQKPG QSPVLVIYQD SKRPSGIPER 60 FSGSNSGNTA TLTISGTQAM DEADYYCQAW DSSTGVFGGG TKLTVL 106 M27-E5 HC 25 EVQLLESGGG LVQPGGSLRL SCAASGFTFS WYLMIWVRQA PGKGLEWVSY IYPSGGFTYY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED MAVYYCARTE GPLSWGYGMD VWGQGTTVTV 120 SSASTKGPSV FPLAPSSKS 139 M28-Bll LC 30 QSVLTQPPSV SVSPGQTATI TCSGDQLGDK YVGWYQQKPG QSPILVIYQD TKRPSGIPER 60 FSGSNSGNTA TLTISGTHTV DEAHYYCQAW DTSTAGFGGG TKLTVL 106 M28-Bll HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS WYTMVWVRQA PGKGLEWVSR IYPSGGWTKY 60 35 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TATYYCAREG LLWFGENAFD IWGQGTMVTV 120 SSASTKGPSV FPLAPSSKS 139 M29-DO9 LC QSALTQPPTV SVSPGQTARI TCSGNKLGDK YVAWYQQKPG QSPMLVIYQD TKRPSRVSER 60 40 FSGSNSANTA TLSISGTQAL DEADYYCQAW DSSIVIFGGG TRLTVL 106 M29-DO9 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS WYTMVWVRQA PGKGLEWVSY IYPSGGATFY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCAMGS YDYIWGFYSD HWGQGTLVTV 120 45 SSASTKGPSV FPLAPSSKS 139 M29-E09 LC QYELTQPPSV SVSPGQTATI TCSGDNLGNK YNSWYQQKPG QSPLLVIYQD TKRPSAIPER 60 FSGSNSGNTA TLTISGTQAM DEADYYCQAW DGNVVFGGGT KLTVL 105 50 M29-E09 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS WYEMGWVRQA PGKGLEWVSS IYSSGGGTMY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARNP QYSGYDRSLS DGAFDIWGQG 120 TMVTVSSAST KGPSVFPLAP SSKS 144 55 M35-GO4 LC 82/151 QDIQMTQSPA TLSLSPGERA TLSCRASQSV SSYLAWYQQK PGQAPRLLIY DASNRATGIP 60 ARFSGSGSGT DFTLTISSLE PEDFAVYYCQ QRSNWPRGFT FGPGTKVDIK 110 M35-GO4 HC 5 EVQLLESGGG LVQPGGSLRL SCAASGFTFS YYHMSWVRQA PGKGLEWVSV ISPSGGSTKY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARGG SSDYAWGSYR RPYYFDYWGQ 120 GTLVTVSSAS TKGPSVFPLA PSSKS 145 M38-F02 LC 10 QSVLTQPPSV SVSPGQTASI TCSGEKLGDK YVSWYQQKPG QSPSLVICED SRRPSGIPER 60 FSGSNSGNTA TLTISGAQPM DEADYYCQAW DSSTAIFGPG TKVTVL 106 M38-F02 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS YYMMVWVRQA PGKGLEWVSY IYSSGGHTVY 60 15 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARDL FLYDFWSKGA FDIWGQGTMV 120 TVSSASTKGP SVFPLAPSSK S 141 M41-All LC QSVLTQPPSV SVSPGQTASI TCSGDKLGDK YTSWYQQRPG QSPVLVIYQD IKRPSGIPER 60 20 FSGSNSGNTA TLTISGTQAM DEADYYCQAW DSPNARVFGS GTKVTVL 107 M41-All HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS HYRMSWVRQA PGKGLEWVSS IYPSGGRTVY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCAKDK FEWRLLFRGI GNDAFDIWGQ 120 25 GTMVTVSSAS TKGPSVFPLA PSSKS 145 M73-DO6 LC QSELTQPPSA SETPGQRVTI SCSGSSSNIG SNTVSWFQQL PGSAPRLLIY NDHRRPSGVP 60 DRFSGSKSGT SASLVISGLQ SQDEADYYCS AWDDSLNGVV FGGGTKLTVL 110 30 M73-DO6 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS RYEMYWVRQA PGKGLEWVSS ISSSGGPTAY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAMYYCAKGT PKWELLLRSI YIENAFDIWG 120 QGTMVTVSSA STKGPSVFPL APSSKS 146 35 M76-DO1 LC QDIVMTQTPP SLPVNPGEPA SISCRSSQSL SDDGNTYLDW YLQRPGQSPQ LLIHTLSYRA 60 SGVPDRFSGS GSGTDFTLKI SRVEAEDVGV YYCMQGTHWP PTFGQGTKVE IK 112 40 M76-DO1 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS FYAMHWVRQA PGKGLEWVSG IVPSGGRTHY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCATDS SGSPNPLFDY WGQGTLVTVS 120 SASTKGPSVF PLAPSPKS 138 45 M110-C12 LC QDIQMTQSPL SLSVTPGEPA SISCRSSLSL LHSNGYNYLD WYVQRPGQSP QLLMYLSSTR 60 ASGVPDRFSG SGSGTDFTLE ISRVEAEDVG VYYCMQPLET PPTFGGGTKV EIK 113 M110-C12 HC 50 EVQLLESGGG LVQPGGSLRL SCAASGFTFS YYEMDWVRQA PGKGLEWVSG ISSSGGHTAY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TATYYCARER RSSSRARYYY GMDVWGQGTT 120 VTVSSASTKG PSVFPLAPSS KS 142 M137-E12 LC 55 QSVLIQPPSV SGIPGQRVTI SCSGNNSNFG SNTVTWYQQL PGTAPKLLIY SDSRRPSGVP 60 DRFSGSRSDT SASLAISGLQ SEDEAEYHCA AWDDSLNGVF GGGTKLTVL 109 83/151 M137-E12 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS DYRMQWVRQA PGKGLEWVSV IVPSGGNTMY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARGG PGSSIAARRA PTGYYGMDVW 120 5 GQGTTVTVSS ASTKGPSVFP LAPSSKS 147 M142-H8 LC QDIQMTQSPS SLSAFVGDRV TITCRASQPI DNYLNWYHQK PGKAPKLLIY AASRLQSGVP 60 SRLSGSGFGT DFTLTISSLQ PEDFGNYYCQ QSYTVPYTFG GGTKVEIR 108 10 M142-HO8 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS AYSMIWVRQA PGKGLEWVSY IRPSGGRTTY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARGG LLLWFRELKS NYFDYWGQGT 120 LVTVSSASTK GPSVFPLAPS SKS 143 15 M145-DO1 LC QDIQMTQSPA TLSLSPGERA TLSCRASQSV SSYLAWYQQK PGQAPRLLIY DASNRATGIP 60 ARFSGSGSGT DFTLTISSLE PEDFAVYYCQ QRSNWPRGFT FGPGTKVDIK 110 20 M145-DO1 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS YYHMSWVRQA PGKGLEWVSV ISPSGGSTKY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARGG SSDYAWGSYR RPYYFDYWGQ 120 GTLVTVSSAS TKGPSVFPLA PSSKS 145 25 M145-Dll LC QSVLTQPPSV SVSPGQTASI TCSGDKLGDK YTSWYQQRPG QSPVLVIYQD IKRPSGIPER 60 FSGSNSGNTA TLTISGTQAM DEADYYCQAW DSPNARVFGS GTKVTVL 107 M145-Dll HC 30 EVQLLESGGG LVQPGGSLRL SCAASGFTFS HYRMSWVRQA PGKGLEWVSS IYPSGGRTVY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCAKDK FEWRLLFRGI GNDAFDIWGQ 120 GTMVTVSSAS TKGPSVFPLA PSSKS 145 M146-E12 LC 35 QDIQMTQSPS SLSASVGDRV TITCRASGDI GNALGWYQQK PGKAPRLLIS DASTLQSGVP 60 LRFSGSGSGT EFTLTISSLQ PEDFATYYCL QGYNYPRTFG QGTKLEIR 108 M146-E12 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS RYIMHWVRQA PGKGLEWVSS ISPSGGLTSY 60 40 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCAREF ENAYHYYYYG MDVWGQGTTV 120 TVSSASTKGP SVFPLAPSSK S 141 M152-A12 LC QDIQMTQSPS SLSASVGDRV TITCRASQSI SSYLSWYQQR PGKAPNLLIY AASSLQSGVP 60 45 SRFSGSGSGT DFTLTISSLQ PEDFATYYCQ QSISIPRTFG QGTKVEVK 108 M152-A12 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS PYFMGWVRQA PGKGLEWVSG IGPSGGSTTY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCAREG PPYSSGWYRG LRQYHFDYWG 120 50 QGTLVTVSSA STKGPSVFPL APSSKS 146 M160-G12 LC QDIQMTQSPS FLSASVGDRV TITCRASQGI SSYLAWYQQK PGKAPKLLIY AASTLQSGVP 60 SRFSGSGSGT EFTLTISSLQ PEDFATYYCQ QLNSYPLTFG GGTKVEIK 108 55 M160-G12 HC 84/151 EVQLLESGGG LVQPGGSLRL SCAASGFTFS HYLMTWVRQA PGKGLEWVSY ISPSGGHTIY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARVA RGIAARSRTS YFDYWGQGTL 120 VTVSSASTKG PSVFPLAPSS KS 142 5 M161-Cll LC QSALTQPPSV SVSPGQTASI TCSGDKLGDK YVSWYQQRPG QSPVLVIYQD TKRPSGIPER 60 FSGSNSGNTA TLTISGTQAV DEADYYCQAW DSSTYVFGGG TKVTVL 106 M161-Cll HC 10 EVQLLESGGG LVQPGGSLRL SCAASGFTFS DYAMKWVRQA PGKGLEWVSS ISSSGGVTQY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCAREE DYSSSWYSRR FDYYYGMDVW 120 GQGTTVTVSS ASTKGPSVFP LAPSSKS 147 M162-A04 LC 15 QDIQMTQSPS TLSASVGDRV TITCRASQSI SSWLAWYQQK PGKAPNLLIY KASTLESGVP 60 SRFSGSGSGT EFTLTISSLQ PDDFATYYCQ QYNTYWTFGQ GTKVEIK 107 M162-A04 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS HYIMMWVRQA PGKGLEWVSG IYSSGGITVY 60 20 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCAYRR TGIPRRDAFD IWGQGTMVTV 120 SSASTKGPSV FPLAPSSKS 139 X67-B03 LC QDIQMTQSPS SLSAFVGDRV TITCRASQPI DNYLNWYHQK PGKAPKLLIY AASRLQSGVP 60 25 SRLSGSGFGT DFTLTISSLQ PEDFGNYYCQ QSYTVPYTFG GGTKVEIR 108 X67-B03 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS AYSMIWVRQA PGKGLEWVSY IRPSGGRTTY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARGG LLLWSRELKS NYFDYWGQGT 120 30 LVTVSSASTK GPSVFPLAPS SKS 143 X67-C03 LC QDIQMTQSPS SLSAFVGDRV TITCRASQPI DNYLNWYHQK PGKAPKLLIY AASRLQSGVP 60 SRLSGSGFGT DFTLTISSLQ PEDFGNYYCQ QSYTVPYTFG GGTKVEIR 108 35 X67-C03 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS AYSMIWVRQA PGKGLEWVSY IRPSGGRTTY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARGG LLLWMRELKS NYFDYWGQGT 120 LVTVSSASTK GPSVFPLAPS SKS 143 40 X67-C09 LC QDIQMTQSPS SLSAFVGDRV TITCRASQPI DNYLNWYHQK PGKAPKLLIY AASRLQSGVP 60 SRLSGSGFGT DFTLTISSLQ PEDFGNYYCQ QSYTVPYTFG GGTKVEIR 108 45 X67-C09 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS AYSMIWVRQA PGKGLEWVSY IRPSGGRTTY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARGG LLLWGRELKS NYFDYWGQGT 120 LVTVSSASTK GPSVFPLAPS SKS 143 50 X67-DO3 LC QDIQMTQSPS SLSAFVGDRV TITCRASQPI DNYLNWYHQK PGKAPKLLIY AASRLQSGVP 60 SRLSGSGFGT DFTLTISSLQ PEDFGNYYCQ QSYTVPYTFG GGTKVEIR 108 X67-DO3 HC 55 EVQLLESGGG LVQPGGSLRL SCAASGFTFS AYSMIWVRQA PGKGLEWVSY IRPSGGRTTY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARGG LLLWNRELKS NYFDYWGQGT 120 85/151 LVTVSSASTK GPSVFPLAPS SKS 143 X67-E04 LC QDIQMTQSPS SLSAFVGDRV TITCRASQPI DNYLNWYHQK PGKAPKLLIY AASRLQSGVP 60 5 SRLSGSGFGT DFTLTISSLQ PEDFGNYYCQ QSYTVPYTFG GGTKVEIR 108 X67-E04 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS AYSMIWVRQA PGKGLEWVSY IRPSGGRTTY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARGG LLLWDRELKS NYFDYWGQGT 120 10 LVTVSSASTK GPSVFPLAPS SKS 143 X67-FO1 LC QDIQMTQSPS SLSAFVGDRV TITCRASQPI DNYLNWYHQK PGKAPKLLIY AASRLQSGVP 60 SRLSGSGFGT DFTLTISSLQ PEDFGNYYCQ QSYTVPYTFG GGTKVEIR 108 15 X67-FO1 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS AYSMIWVRQA PGKGLEWVSY IRPSGGRTTY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARGG LLLWQRELKS NYFDYWGQGT 120 LVTVSSASTK GPSVFPLAPS SKS 143 20 X67-F1O LC QDIQMTQSPS SLSAFVGDRV TITCRASQPI DNYLNWYHQK PGKAPKLLIY AASRLQSGVP 60 SRLSGSGFGT DFTLTISSLQ PEDFGNYYCQ QSYTVPYTFG GGTKVEIR 108 25 X67-F1O HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS AYSMIWVRQA PGKGLEWVSY IRPSGGRTTY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARGG LLLWTRELKS NYFDYWGQGT 120 LVTVSSASTK GPSVFPLAPS SKS 143 30 X67-GO4 LC QDIQMTQSPS SLSAFVGDRV TITCRASQPI DNYLNWYHQK PGKAPKLLIY AASRLQSGVP 60 SRLSGSGFGT DFTLTISSLQ PEDFGNYYCQ QSYTVPYTFG GGTKVEIR 108 X67-GO4 HC 35 EVQLLESGGG LVQPGGSLRL SCAASGFTFS AYSMIWVRQA PGKGLEWVSY IRPSGGRTTY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARGG LLLWARELKS NYFDYWGQGT 120 LVTVSSASTK GPSVFPLAPS SKS 143 X67-HO4 LC 40 QDIQMTQSPS SLSAFVGDRV TITCRASQPI DNYLNWYHQK PGKAPKLLIY AASRLQSGVP 60 SRLSGSGFGT DFTLTISSLQ PEDFGNYYCQ QSYTVPYTFG GGTKVEIR 108 X67-HO4 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS AYSMIWVRQA PGKGLEWVSY IRPSGGRTTY 60 45 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARGG LLLWERELKS NYFDYWGQGT 120 LVTVSSASTK GPSVFPLAPS SKS 143 Note: The variable sequence of X81-BO1 is the same as X63-G06 (Fab version of X81-B01, which is an IgG), and is shown in Table 11. 50 86/151 Example 4: Lead Antibody Inhibitors Antibodies were selected as lead plasma kallikrein inhibitors on the basis of apparent inhibition constant (Ki,app), specificity with respect to lack of inhibition of other serine proteases, inhibition of bradykinin generation, and lack of binding to plasma 5 prekallikrein (Table 7). Plasma kallikrein circulates in the plasma as an inactive zymogen (prekallikrein) at a concentration of approximately 500 nM. Antibodies that bound prekallikrein may be rendered inaccessible towards active plasma kallikrein inhibition and could substantially increase the in vivo dose required for efficacy. Therefore, a surface plasmon resonance (SPR) assay was used to identify antibodies that 10 do not bind prekallikrein (data not shown). Specifically, human IgGs (X81-B01, M162 A04 (R84-H05); M160-G12 (R84-D02); and M142-H08) were captured on a CM5 chip using an anti-human Fc surface and 100 nM of plasma kallikrein or 100 nM or 500 nM prekallikrein. The prekallikrein was treated with aprotinin-sepharose to remove active plasma kallikrein. The prekallikrein used for X81-BO was buffer exchanged into the 15 exact preparation of SPR running buffer (HEPES buffered saline) to avoid the refractive index shift that was observed with three other antibodies that were tested: M162-A04 (R84-H05); M160-G12 (R84-D02); and M142-H08. Of the antibodies listed in Table 7, only M142-H08 inhibits human plasma kallikrein with a subnanomolar Ki,app. However, when M142-H08 was produced as an 20 IgG it was found to be cleaved in the CDRJ of the heavy chain. Consequently, we decided to undertake two approaches to improve the affinity: 1) affinity maturation of M162-A04 and M160-G12 using a novel form of light chain shuffling called ROLIC (Rapid Qptimization of Light Chains) (see, e.g., WO 2009/102927 and U.S. 2009 0215119); and 2) sequence optimization of M142-H08 in order to prevent the cleavage of 25 the IgG that occurs while retaining the binding and inhibitor properties of M142-H08. Table 7. Top Ranking Antibody Inhibitors of PKal Before Affinity Maturation or Sequence Optimization Criteria M162-A04 M160-G12 M142-H08a Ki,app human pKal 2 nM (as an 5.6 nM (as 0.6 nM (as a IgG) an IgG) Fab) 87/151 Ki,app rodent pKal 2 nM <1 nM - 1 nM (mouse and (mouse) (mouse and rat) rat) Binds prekallikrein? No No No Specific inhibitor with Yes Yes Yes respect to fXIa, plasmin, and trypsin Inhibits bradykinin Yes Yes Yes generation aWhen M142-H08 was produced as an IgG it was determined to be cleaved in the CDR3 of its heavy chain (GGLLLWFR-ELKSNYFDY). 5 Example 5: Sequence Optimization of M142-H08 Of the antibodies listed in Table 7, only M142-H08 inhibits human pKal with a subnanomolar Kiapp. However, when M142-H08 was produced as an IgG it was found to be cleaved in the CDR3 of the heavy chain. M142-H08 was found by mass spectrometry to be cleaved after the arginine in the "WFR" sequence of the HC-CDR3 sequence 10 (GGLLLWFRELKSNYFDY). This cleavage suggests that a protease from the cells used to express the antibody (both CHO and 293T human kidney cells) is enzymatically cleaving the antibody at a single specific site. We mutated the HC-CDR3 sequence of M142-H08 in order to identify amino acid substitutions that prevent the cleavage of the IgG that occurs while retaining the binding and inhibitor properties of M142-H08. 15 Previous experience with similarly "clipped" antibodies suggested that focusing simply on the putative P1 position (protease subsite 1, see Table 8) may not be sufficient to identify antibodies that retain potent inhibition of the target enzyme while not being clipped by a host cell protease. Therefore, we created a small library of single point mutations in the region around the cleavage site in order to identify variants of M142 20 H08 that are not clipped but are still potent pKal inhibitors. We refer to this library as the "CDR3 by Design" library. The small library was constructed using a PCR primer that contains the randomized codon NNK at either the P3, the P2, the P1, or the P1' site. This 88/151 results in a small library where each of the 4 positions may contain any of the 20 amino acids (20 +20 + 20 + 20 = 80 members). Using PCR, this library was cloned into the M142-H08 Fab sequence in the pMid2l vector, which is a standard phagemid vector. 5 Table 8. Primer sequences Primer Name Sequence N P3 P2 P1 P1' P2' G G L L L W F R E L K S N Y 559A.P1.top GGC GGT CTA TTA CTA TGG TTC NNK GAG CTG 20 AAG TCT AAC TAC 559A.P2.top GGC GGT CTA TTA CTA TGG NNK AGG GAG CTG 20 AAG TCT AAC TAC 559A.P3.top GGC GGT CTA TTA CTA NNK TTC AGG GAG CTG 20 AAG TCT AAC TAC 559A.Plp.top GGC GGT CTA TTA CTA TGG TTC AGG NNK CTG 20 AAG TCT AAC TAC By DNA sequencing, we recovered 61 of the possible 80 antibodies (Table 9). These antibodies were produced as Fab fragments in small scale (-20 kg) and tested for inhibition against human pKal in an in vitro protease cleavage assay using Pro-Phe-Arg 10 aminomethylcoumarin as the synthetic peptide substrate. The Fabs that were found to be inhibitors of human pKal were subcloned into our pBRHlf vector (a vector for transient expression of IgGs in 293T cells) for conversion to full length human IgG1 antibodies. Five antibodies were then expressed in 293T cells and purified by protein A sepharose chromatography. The antibodies were analyzed by SDS-PAGE to determine which of 15 the inhibitory mutants are not cleaved by the host cell protease(s) (data not shown). The cleaved antibodies (559A-X67-G05, 559A-X67-HO1, 559A-X67-G09) had an extra band that migrated between the 38 and the 49 kDa molecular weight marker. This band is absent in the 559A-X67-H04 and 559A-X67-D03 antibodies, which indicates that these antibodies are intact. 89/151 Ki,app values were determined by steady state enzyme kinetics for those that were shown by SDS-PAGE to be not cleaved (Table 9). Interestingly, the P2 position was the only position where amino acid substitutions yielded intact antibody inhibitors of pKal. Of the 14 different mutations that were recovered at the P3 position (Table 9), only one 5 mutant (W to L) was found to be a pKal inhibitor as a Fab but it was subsequently shown to be clipped as an IgG. None of the 16 different mutations at the P1 position (Table 9) were found to be pKal inhibitors. Eight of the 15 different mutations at the Pl' position were found to be inhibitors of pKal as a Fab but all were clipped as an IgG. Consequently, only mutations at the P2 position led to antibody inhibitors that were not 10 clipped during expression. Of the 16 different mutations that were recovered at the P2 position (Table 9), eight mutants were found to be a pKal inhibitor as a Fab but it was subsequently shown to be clipped as an IgG. Four mutants at the P2 position were found to have subnanomolar Ki,app values: X67-G04 (F to A), X67-C03 (F to M), X67-F01 (F to Q) and X67-D03 (F to N). The antibody with the highest potency is X67-D03 (Ki,app 15 0.1 nM). The two antibodies shown in Table 10 were not cleaved when expressed as IgGs and were found to inhibit pKal with a subnanomolar Ki,app. DNA and amino acid sequence alignments of the light chains of nongermlined (X63-G06) and germlined, codon optimized (X81-B01) versions of the same antibody discovered using ROLIC affinity maturation are shown in FIGURES 3 and 4, 20 respectively. DNA and amino acid sequence alignments of the heavy chains of nongermlined (X63-G06) and germlined, codon optimized (X81-B01) versions of the same antibody discovered using ROLIC affinity maturation are shown in FIGURES 5 and 6, respectively. 25 Table 9. HV-CDR3 Sequences Obtained from "CDR3 by Design" Library* Inhibit Intact Ki,app as a as an as an Mutation Fab? IgG? IgG Site Antibody I.D. HV-CDR3 (nM) Yes No 0.2 Parental X69-C09 GGLLLWFRELKSNYFDY 90/151 P3 X68-E07 GGLLLAFRELKSNYFDY No n/a n/a P3 X68-E12 GGLLLCFRELKSNYFDY No n/a n/a P3 X68-A03 GGLLLDFRELKSNYFDY No n/a n/a P3 X68-E03 GGLLLEFRELKSNYFDY No n/a n/a P3 X68-A12 GGLLLGFRELKSNYFDY No n/a n/a P3 X68-D11 GGLLLKFRELKSNYFDY No n/a n/a P3 X68-EO1 GGLLLLFRELKSNYFDY Yes No n/a P3 X68-F05 GGLLLMFRELKSNYFDY No n/a n/a P3 X68-D1O GGLLLPFRELKSNYFDY No n/a n/a P3 X68-F1O GGLLLQFRELKSNYFDY No n/a n/a P3 X68-GO1 GGLLLRFRELKSNYFDY No n/a n/a P3 X68-G05 GGLLLSFRELKSNYFDY No n/a n/a P3 X68-F12 GGLLLTFRELKSNYFDY No n/a n/a P3 X68-H04 GGLLLVFRELKSNYFDY No n/a n/a P2 X67-G04 GGLLLWARELKSNYFDY Yes Yes 0.35 P2 X67-GO1 GGLLLWCRELKSNYFDY No n/a n/a P2 X67-E04 GGLLLWDRELKSNYFDY Yes Yes 1.3 P2 X67-H04 GGLLLWERELKSNYFDY Yes Yes 3.6 P2 X67-C09 GGLLLWGRELKSNYFDY Yes Yes 8.6 P2 X67-B04 GGLLLWKRELKSNYFDY Yes No n/a P2 X67-G09 GGLLLWLRELKSNYFDY Yes No n/a P2 X67-C03 GGLLLWMRELKSNYFDY Yes Yes 0.7 P2 X67-DO3 GGLLLWNRELKSNYFDY Yes Yes 0.1 P2 X67-B05 GGLLLWPRELKSNYFDY No n/a n/a P2 X67-FO1 GGLLLWQRELKSNYFDY Yes Yes 0.9 P2 X67-G05 GGLLLWRRELKSNYFDY Yes No n/a 91/151 P2 X67-B03 GGLLLWSRELKSNYFDY Yes Yes 2.1 P2 X67-F1O GGLLLWTRELKSNYFDY Yes Yes 1.3 P2 X67-HO1 GGLLLWWRELKSNYFDY Yes No n/a P2 X67-FO8 GGLLLWYRELKSNYFDY Yes No n/a P1 X66-E09 GGLLLWFAELKSNYFDY No n/a n/a P1 X66-B05 GGLLLWFCELKSNYFDY No n/a n/a P1 X66-DO3 GGLLLWFEELKSNYFDY No n/a n/a P1 X66-H04 GGLLLWFFELKSNYFDY No n/a n/a P1 X66-H02 GGLLLWFGELKSNYFDY No n/a n/a P1 X66-C11 GGLLLWFHELKSNYFDY No n/a n/a P1 X66-A07 GGLLLWFKELKSNYFDY No n/a n/a P1 X66-C03 GGLLLWFLELKSNYFDY No n/a n/a P1 X66-G05 GGLLLWFMELKSNYFDY No n/a n/a P1 X66-F1O GGLLLWFPELKSNYFDY No n/a n/a P1 X66-E04 GGLLLWFQELKSNYFDY No n/a n/a P1 X66-FO1 GGLLLWFSELKSNYFDY No n/a n/a P1 X66-H11 GGLLLWFTELKSNYFDY No n/a n/a P1 X66-C02 GGLLLWFVELKSNYFDY No n/a n/a P1 X66-F09 GGLLLWFWELKSNYFDY No n/a n/a P1 X66-GO8 GGLLLWFYELKSNYFDY No n/a n/a Pl' X69-DO8 GGLLLWFRALKSNYFDY No n/a n/a Pl' X69-B02 GGLLLWFRCLKSNYFDY No n/a n/a Pl' X69-D09 GGLLLWFRGLKSNYFDY Yes No n/a Pl' X69-D02 GGLLLWFRHLKSNYFDY No n/a n/a Pl' X69-A12 GGLLLWFRKLKSNYFDY No n/a n/a Pl' X69-F05 GGLLLWFRLLKSNYFDY Yes No n/a 92/151 P1' X69-BO8 GGLLLWFRNLKSNYFDY Yes No n/a P1' X69-A10 GGLLLWFRPLKSNYFDY No n/a n/a P1' X69-A09 GGLLLWFRQLKSNYFDY Yes No n/a P1' X69-E05 GGLLLWFRRLKSNYFDY No n/a n/a P1' X69-F09 GGLLLWFRSLKSNYFDY Yes No n/a P1' X69-F01 GGLLLWFRTLKSNYFDY Yes No n/a P1' X69-C12 GGLLLWFRVLKSNYFDY Yes No n/a P1' X69-E01 GGLLLWFRWLKSNYFDY Yes No n/a P1' X69-H10 GGLLLWFRYLKSNYFDY No n/a n/a *All of these antibodies are single point mutations of the M142-H08 sequence. Amino acid sequences of light chain (LC) and heavy chain (HC) variable domain of pKal antibodies with designed HC CDR3s are shown below. 5 X68-E07 LC QDIQMTQSPS SLSAFVGDRV TITCRASQPI DNYLNWYHQK PGKAPKLLIY AASRLQSGVP 60 SRLSGSGFGT DFTLTISSLQ PEDFGNYYCQ QSYTVPYTFG GGTKVEIR 108 10 X68-E07 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS AYSMIWVRQA PGKGLEWVSY IRPSGGRTTY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARGG LLLAFRELKS NYFDYWGQGT 120 LVTVSSASTK GPSVFPLAPS SKS 143 15 X68-E12 LC QDIQMTQSPS SLSAFVGDRV TITCRASQPI DNYLNWYHQK PGKAPKLLIY AASRLQSGVP 60 SRLSGSGFGT DFTLTISSLQ PEDFGNYYCQ QSYTVPYTFG GGTKVEIR 108 X68-E12 HC 20 EVQLLESGGG LVQPGGSLRL SCAASGFTFS AYSMIWVRQA PGKGLEWVSY IRPSGGRTTY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARGG LLLCFRELKS NYFDYWGQGT 120 LVTVSSASTK GPSVFPLAPS SKS 143 X68-A03 LC 25 QDIQMTQSPS SLSAFVGDRV TITCRASQPI DNYLNWYHQK PGKAPKLLIY AASRLQSGVP 60 SRLSGSGFGT DFTLTISSLQ PEDFGNYYCQ QSYTVPYTFG GGTKVEIR 108 X68-A03 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS AYSMIWVRQA PGKGLEWVSY IRPSGGRTTY 60 30 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARGG LLLDFRELKS NYFDYWGQGT 120 LVTVSSASTK GPSVFPLAPS SKS 143 X68-E03 LC QDIQMTQSPS SLSAFVGDRV TITCRASQPI DNYLNWYHQK PGKAPKLLIY AASRLQSGVP 60 93/151 SRLSGSGFGT DFTLTISSLQ PEDFGNYYCQ QSYTVPYTFG GGTKVEIR 108 X68-E03 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS AYSMIWVRQA PGKGLEWVSY IRPSGGRTTY 60 5 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARGG LLLEFRELKS NYFDYWGQGT 120 LVTVSSASTK GPSVFPLAPS SKS 143 X68-A12 LC QDIQMTQSPS SLSAFVGDRV TITCRASQPI DNYLNWYHQK PGKAPKLLIY AASRLQSGVP 60 10 SRLSGSGFGT DFTLTISSLQ PEDFGNYYCQ QSYTVPYTFG GGTKVEIR 108 X68-A12 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS AYSMIWVRQA PGKGLEWVSY IRPSGGRTTY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARGG LLLGFRELKS NYFDYWGQGT 120 15 LVTVSSASTK GPSVFPLAPS SKS 143 X68-Dll LC QDIQMTQSPS SLSAFVGDRV TITCRASQPI DNYLNWYHQK PGKAPKLLIY AASRLQSGVP 60 SRLSGSGFGT DFTLTISSLQ PEDFGNYYCQ QSYTVPYTFG GGTKVEIR 108 20 X68-Dll HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS AYSMIWVRQA PGKGLEWVSY IRPSGGRTTY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARGG LLLKFRELKS NYFDYWGQGT 120 LVTVSSASTK GPSVFPLAPS SKS 143 25 X68-E01 LC QDIQMTQSPS SLSAFVGDRV TITCRASQPI DNYLNWYHQK PGKAPKLLIY AASRLQSGVP 60 SRLSGSGFGT DFTLTISSLQ PEDFGNYYCQ QSYTVPYTFG GGTKVEIR 108 30 X68-EO1 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS AYSMIWVRQA PGKGLEWVSY IRPSGGRTTY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARGG LLLLFRELKS NYFDYWGQGT 120 LVTVSSASTK GPSVFPLAPS SKS 143 35 X68-F05 LC QDIQMTQSPS SLSAFVGDRV TITCRASQPI DNYLNWYHQK PGKAPKLLIY AASRLQSGVP 60 SRLSGSGFGT DFTLTISSLQ PEDFGNYYCQ QSYTVPYTFG GGTKVEIR 108 X68-F05 HC 40 EVQLLESGGG LVQPGGSLRL SCAASGFTFS AYSMIWVRQA PGKGLEWVSY IRPSGGRTTY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARGG LLLMFRELKS NYFDYWGQGT 120 LVTVSSASTK GPSVFPLAPS SKS 143 X68-D1O LC 45 QDIQMTQSPS SLSAFVGDRV TITCRASQPI DNYLNWYHQK PGKAPKLLIY AASRLQSGVP 60 SRLSGSGFGT DFTLTISSLQ PEDFGNYYCQ QSYTVPYTFG GGTKVEIR 108 X68-D1O HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS AYSMIWVRQA PGKGLEWVSY IRPSGGRTTY 60 50 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARGG LLLPFRELKS NYFDYWGQGT 120 LVTVSSASTK GPSVFPLAPS SKS 143 X68-F1O LC QDIQMTQSPS SLSAFVGDRV TITCRASQPI DNYLNWYHQK PGKAPKLLIY AASRLQSGVP 60 55 SRLSGSGFGT DFTLTISSLQ PEDFGNYYCQ QSYTVPYTFG GGTKVEIR 108 94/151 X68-F1O HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS AYSMIWVRQA PGKGLEWVSY IRPSGGRTTY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARGG LLLQFRELKS NYFDYWGQGT 120 LVTVSSASTK GPSVFPLAPS SKS 143 5 X68-G01 LC QDIQMTQSPS SLSAFVGDRV TITCRASQPI DNYLNWYHQK PGKAPKLLIY AASRLQSGVP 60 SRLSGSGFGT DFTLTISSLQ PEDFGNYYCQ QSYTVPYTFG GGTKVEIR 108 10 X68-G01 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS AYSMIWVRQA PGKGLEWVSY IRPSGGRTTY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARGG LLLRFRELKS NYFDYWGQGT 120 LVTVSSASTK GPSVFPLAPS SKS 143 15 X68-G05 LC QDIQMTQSPS SLSAFVGDRV TITCRASQPI DNYLNWYHQK PGKAPKLLIY AASRLQSGVP 60 SRLSGSGFGT DFTLTISSLQ PEDFGNYYCQ QSYTVPYTFG GGTKVEIR 108 X68-G05 HC 20 EVQLLESGGG LVQPGGSLRL SCAASGFTFS AYSMIWVRQA PGKGLEWVSY IRPSGGRTTY 60 ADSVKGRFTI SRDNSKNILY LQMNSLRAED TAVYYCARGG LLLSFRELKS NYFDYWGQGT 120 LVTVSSASTK GPSVFPLAPS SKS 143 X68-F12 LC 25 QDIQMTQSPS SLSAFVGDRV TITCRASQPI DNYLNWYHQK PGKAPKLLIY AASRLQSGVP 60 SRLSGSGFGT DFTLTISSLQ PEDFGNYYCQ QSYTVPYTFG GGTKVEIR 108 X68-F12 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS AYSMIWVRQA PGKGLEWVSY IRPSGGRTTY 60 30 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARGG LLLTFRELKS NYFDYWGQGT 120 LVTVSSASTK GPSVFPLAPS SKS 143 X68-HO4 LC QDIQMTQSPS SLSAFVGDRV TITCRASQPI DNYLNWYHQK PGKAPKLLIY AASRLQSGVP 60 35 SRLSGSGFGT DFTLTISSLQ PEDFGNYYCQ QSYTVPYTFG GGTKVEIR 108 X68-HO4 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS AYSMIWVRQA PGKGLEWVSY IRPSGGRTTY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARGG LLLVFRELKS NYFDYWGQGT 120 40 LVTVSSASTK GPSVFPLAPS SKS 143 X67-GO4 LC QDIQMTQSPS SLSAFVGDRV TITCRASQPI DNYLNWYHQK PGKAPKLLIY AASRLQSGVP 60 SRLSGSGFGT DFTLTISSLQ PEDFGNYYCQ QSYTVPYTFG GGTKVEIR 108 45 X67-GO4 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS AYSMIWVRQA PGKGLEWVSY IRPSGGRTTY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARGG LLLWARELKS NYFDYWGQGT 120 LVTVSSASTK GPSVFPLAPS SKS 143 50 X67-GO1 LC QDIQMTQSPS SLSAFVGDRV TITCRASQPI DNYLNWYHQK PGKAPKLLIY AASRLQSGVP 60 SRLSGSGFGT DFTLTISSLQ PEDFGNYYCQ QSYTVPYTFG GGTKVEIR 108 55 X67-GO1 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS AYSMIWVRQA PGKGLEWVSY IRPSGGRTTY 60 95/151 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARGG LLLWCRELKS NYFDYWGQGT 120 LVTVSSASTK GPSVFPLAPS SKS 143 X67-E04 LC 5 QDIQMTQSPS SLSAFVGDRV TITCRASQPI DNYLNWYHQK PGKAPKLLIY AASRLQSGVP 60 SRLSGSGFGT DFTLTISSLQ PEDFGNYYCQ QSYTVPYTFG GGTKVEIR 108 X67-E04 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS AYSMIWVRQA PGKGLEWVSY IRPSGGRTTY 60 10 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARGG LLLWDRELKS NYFDYWGQGT 120 LVTVSSASTK GPSVFPLAPS SKS 143 X67-HO4 LC QDIQMTQSPS SLSAFVGDRV TITCRASQPI DNYLNWYHQK PGKAPKLLIY AASRLQSGVP 60 15 SRLSGSGFGT DFTLTISSLQ PEDFGNYYCQ QSYTVPYTFG GGTKVEIR 108 X67-HO4 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS AYSMIWVRQA PGKGLEWVSY IRPSGGRTTY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARGG LLLWERELKS NYFDYWGQGT 120 20 LVTVSSASTK GPSVFPLAPS SKS 143 X66-E09 LC QDIQMTQSPS SLSAFVGDRV TITCRASQPI DNYLNWYHQK PGKAPKLLIY AASRLQSGVP 60 SRLSGSGFGT DFTLTISSLQ PEDFGNYYCQ QSYTVPYTFG GGTKVEIR 108 25 X66-E09 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS AYSMIWVRQA PGKGLEWVSY IRPSGGRTTY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARGG LLLWFAELKS NYFDYWGQGT 120 LVTVSSASTK GPSVFPLAPS SKS 143 30 X66-B05 LC QDIQMTQSPS SLSAFVGDRV TITCRASQPI DNYLNWYHQK PGKAPKLLIY AASRLQSGVP 60 SRLSGSGFGT DFTLTISSLQ PEDFGNYYCQ QSYTVPYTFG GGTKVEIR 108 35 X66-B05 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS AYSMIWVRQA PGKGLEWVSY IRPSGGRTTY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARGG LLLWFCELKS NYFDYWGQGT 120 LVTVSSASTK GPSVFPLAPS SKS 143 40 X66-DO3 LC QDIQMTQSPS SLSAFVGDRV TITCRASQPI DNYLNWYHQK PGKAPKLLIY AASRLQSGVP 60 SRLSGSGFGT DFTLTISSLQ PEDFGNYYCQ QSYTVPYTFG GGTKVEIR 108 X66-DO3 HC 45 EVQLLESGGG LVQPGGSLRL SCAASGFTFS AYSMIWVRQA PGKGLEWVSY IRPSGGRTTY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARGG LLLWFEELKS NYFDYWGQGT 120 LVTVSSASTK GPSVFPLAPS SKS 143 X66-HO4 LC 50 QDIQMTQSPS SLSAFVGDRV TITCRASQPI DNYLNWYHQK PGKAPKLLIY AASRLQSGVP 60 SRLSGSGFGT DFTLTISSLQ PEDFGNYYCQ QSYTVPYTFG GGTKVEIR 108 X66-HO4 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS AYSMIWVRQA PGKGLEWVSY IRPSGGRTTY 60 55 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARGG LLLWFFELKS NYFDYWGQGT 120 LVTVSSASTK GPSVFPLAPS SKS 143 96/151 X66-HO2 LC QDIQMTQSPS SLSAFVGDRV TITCRASQPI DNYLNWYHQK PGKAPKLLIY AASRLQSGVP 60 SRLSGSGFGT DFTLTISSLQ PEDFGNYYCQ QSYTVPYTFG GGTKVEIR 108 5 X66-HO2 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS AYSMIWVRQA PGKGLEWVSY IRPSGGRTTY 60 ADSVKGRFTI SRDNSKNTLY LQMHSLRAED TAVYYCARGG LLLWFGELKS NYFDYWGQGT 120 LVTVSSASTK GPSVFPLAPS SKS 143 10 X66-C11 LC QDIQMTQSPS SLSAFVGDRV TITCRASQPI DNYLNWYHQK PGKAPKLLIY AASRLQSGVP 60 SRLSGSGFGT DFTLTISSLQ PEDFGNYYCQ QSYTVPYTFG GGTKVEIR 108 15 X66-C11 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS AYSMIWVRQA PGKGLEWVSY IRPSGGRTTY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARGG LLLWFHELKS NYFDYWGQGT 120 LVTVSSASTK GPSVFPLAPS SKS 143 20 X66-A07 LC QDIQMTQSPS SLSAFVGDRV TITCRASQPI DNYLNWYHQK PGKAPKLLIY AASRLQSGVP 60 SRLSGSGFGT DFTLTISSLQ PEDFGNYYCQ QSYTVPYTFG GGTKVEIR 108 X66-A07 HC 25 EVQLLESGGG LVQPGGSLRL SCAASGFTFS AYSMIWVRQA PGKGLEWVSY IRPSGGRTTY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARGG LLLWFKELKS NYFDYWGQGT 120 LVTVSSASTK GPSVFPLAPS SKS 143 X66-C03 LC 30 QDIQMTQSPS SLSAFVGDRV TITCRASQPI DNYLNWYHQK PGKAPKLLIY AASRLQSGVP 60 SRLSGSGFGT DFTLTISSLQ PEDFGNYYCQ QSYTVPYTFG GGTKVEIR 108 X66-C03 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS AYSMIWVRQA PGKGLEWVSY IRPSGGRTTY 60 35 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARGG LLLWFLELKS NYFDYWGQGT 120 LVTVSSASTK GPSVFPLAPS SKS 143 X66-G05 LC QDIQMTQSPS SLSAFVGDRV TITCRASQPI DNYLNWYHQK PGKAPKLLIY AASRLQSGVP 60 40 SRLSGSGFGT DFTLTISSLQ PEDFGNYYCQ QSYTVPYTFG GGTKVEIR 108 X66-G05 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS AYSMIWVRQA PGKGLEWVSY IRPSGGRTTY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARGG LLLWFMELKS NYFDYWGQGT 120 45 LVTVSSASTK GPSVFPLAPS SKS 143 X66-F1O LC QDIQMTQSPS SLSAFVGDRV TITCRASQPI DNYLNWYHQK PGKAPKLLIY AASRLQSGVP 60 SRLSGSGFGT DFTLTISSLQ PEDFGNYYCQ QSYTVPYTFG GGTKVEIR 108 50 X66-F1O HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS AYSMIWVRQA PGKGLEWVSY IRPSGGRTTY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARGG LLLWFPELKS NYFDYWGQGT 120 LVTVSSASTK GPSVFPLAPS SKS 143 55 X66-E04 LC 97/151 QDIQMTQSPS SLSAFVGDRV TITCRASQPI DNYLNWYHQK PGKAPKLLIY AASRLQSGVP 60 SRLSGSGFGT DFTLTISSLQ PEDFGNYYCQ QSYTVPYTFG GGTKVEIR 108 X66-E04 HC 5 EVQLLESGGG LVQPGGSLRL SCAASGFTFS AYSMIWVRQA PGKGLEWVSY IRPSGGRTTY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARGG LLLWFQELKS NYFDYWGQGT 120 LVTVSSASTK GPSVFPLAPS SKS 143 X69-D08 LC 10 QDIQMTQSPS SLSAFVGDRV TITCRASQPI DNYLNWYHQK PGKAPKLLIY AASRLQSGVP 60 SRLSGSGFGT DFTLTISSLQ PEDFGNYYCQ QSYTVPYTFG GGTKVEIR 108 X69-D08 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS AYSMIWVRQA PGKGLEWVSY IRPSGGRTTY 60 15 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARGG LLLWFRALKS NYFDYWGQGT 120 LVTVSSASTK GPSVFPLAPS SKS 143 X69-B02 LC QDIQMTQSPS SLSAFVGDRV TITCRASQPI DNYLNWYHQK PGKAPKLLIY AASRLQSGVP 60 20 SRLSGSGFGT DFTLTISSLQ PEDFGNYYCQ QSYTVPYTFG GGTKVEIR 108 X69-B02 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS AYSMIWVRQA PGKGLEWVSY IRPSGGRTTY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARGG LLLWFRCLKS NYFDYWGQGT 120 25 LVTVSSASTK GPSVFPLAPS SKS 143 X69-C09 LC QDIQMTQSPS SLSAFVGDRV TITCRASQPI DNYLNWYHQK PGKAPKLLIY AASRLQSGVP 60 SRLSGSGFGT DFTLTISSLQ PEDFGNYYCQ QSYTVPYTFG GGTKVEIR 108 30 X69-C09 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS AYSMIWVRQA PGKGLEWVSY IRPSGGRTTY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARGG LLLWFRELKS NYFDYWGQGT 120 LVTVSSASTK GPSVFPLAPS SKS 143 35 X69-DO9 LC QDIQMTQSPS SLSAFVGDRV TITCRASQPI DNYLNWYHQK PGKAPKLLIY AASRLQSGVP 60 SRLSGSGFGT DFTLTISSLQ PEDFGNYYCQ QSYTVPYTFG GGTKVEIR 108 40 X69-DO9 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS AYSMIWVRQA PGKGLEWVSY IRPSGGRTTY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARGG LLLWFRGLKS NYFDYWGQGT 120 LVTVSSASTK GPSVFPLAPS SKS 143 45 X69-DO2 LC QDIQMTQSPS SLSAFVGDRV TITCRASQPI DNYLNWYHQK PGKAPKLLIY AASRLQSGVP 60 SRLSGSGFGT DFTLTISSLQ PEDFGNYYCQ QSYTVPYTFG GGTKVEIR 108 X69-DO2 HC 50 EVQLLESGGG LVQPGGSLRL SCAASGFTFS AYSMIWVRQA PGKGLEWVSY IRPSGGRTTY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARGG LLLWFRHLKS NYFDYWGQGT 120 LVTVSSASTK GPSVFPLAPS SKS 143 X69-A12 LC 55 QDIQMTQSPS SLSAFVGDRV TITCRASQPI DNYLNWYHQK PGKAPKLLIY AASRLQSGVP 60 SRLSGSGFGT DFTLTISSLQ PEDFGNYYCQ QSYTVPYTFG GGTKVEIR 108 98/151 X69-A12 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS AYSMIWVRQA PGKGLEWVSY IRPSGGRTTY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARGG LLLWFRKLKS NYFDYWGQGT 120 5 LVTVSSASTK GPSVFPLAPS SKS 143 X69-F05 LC QDIQMTQSPS SLSAFVGDRV TITCRASQPI DNYLNWYHQK PGKAPKLLIY AASRLQSGVP 60 SRLSGSGFGT DFTLTISSLQ PEDFGNYYCQ QSYTVPYTFG GGTKVEIR 108 10 X69-F05 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS AYSMIWVRQA PGKGLEWVSY IRPSGGRTTY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARGG LLLWFRLLKS NYFDYWGQGT 120 LVTVSSASTK GPSVFPLAPS SKS 143 15 X69-B08 LC QDIQMTQSPS SLSAFVGDRV TITCRASQPI DNYLNWYHQK PGKAPKLLIY AASRLQSGVP 60 SRLSGSGFGT DFTLTISSLQ PEDFGNYYCQ QSYTVPYTFG GGTKVEIR 108 20 X69-B08 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS AYSMIWVRQA PGKGLEWVSY IRPSGGRTTY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARGG LLLWFRNLKS NYFDYWGQGT 120 LVTVSSASTK GPSVFPLAPS SKS 143 25 X69-A10 LC QDIQMTQSPS SLSAFVGDRV TITCRASQPI DNYLNWYHQK PGKAPKLLIY AASRLQSGVP 60 SRLSGSGFGT DFTLTISSLQ PEDFGNYYCQ QSYTVPYTFG GGTKVEIR 108 X69-A10 HC 30 EVQLLESGGG LVQPGGSLRL SCAASGFTFS AYSMIWVRQA PGKGLEWVSY IRPSGGRTTY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARGG LLLWFRPLKS NYFDYWGQGT 120 LVTVSSASTK GPSVFPLAPS SKS 143 X69-A09 LC 35 QDIQMTQSPS SLSAFVGDRV TITCRASQPI DNYLNWYHQK PGKAPKLLIY AASRLQSGVP 60 SRLSGSGFGT DFTLTISSLQ PEDFGNYYCQ QSYTVPYTFG GGTKVEIR 108 X69-A09 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS AYSMIWVRQA PGKGLEWVSY IRPSGGRTTY 60 40 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARGG LLLWFRQLKS NYFDYWGQGT 120 LVTVSSASTK GPSVFPLAPS SKS 143 X69-E05 LC QDIQMTQSPS SLSAFVGDRV TITCRASQPI DNYLNWYHQK PGKAPKLLIY AASRLQSGVP 60 45 SRLSGSGFGT DFTLTISSLQ PEDFGNYYCQ QSYTVPYTFG GGTKVEIR 108 X69-E05 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS AYSMIWVRQA PGKGLEWVSY IRPSGGRTTY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARGG LLLWFRRLKS NYFDYWGQGT 120 50 LVTVSSASTK GPSVFPLAPS SKS 143 X69-F09 LC QDIQMTQSPS SLSAFVGDRV TITCRASQPI DNYLNWYHQK PGKAPKLLIY AASRLQSGVP 60 SRLSGSGFGT DFTLTISSLQ PEDFGNYYCQ QSYTVPYTFG GGTKVEIR 108 55 X69-F09 HC 99/151 EVQLLESGGG LVQPGGSLRL SCAASGFTFS AYSMIWVRQA PGKGLEWVSY IRPSGGRTTY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARGG LLLWFRSLKS NYFDYWGQGT 120 LVTVSSASTK GPSVFPLAPS SKS 143 5 X69-F01 LC QDIQMTQSPS SLSAFVGDRV TITCRASQPI DNYLNWYHQK PGKAPKLLIY AASRLQSGVP 60 SRLSGSGFGT DFTLTISSLQ PEDFGNYYCQ QSYTVPYTFG GGTKVEIR 108 X69-F01 HC 10 EVQLLESGGG LVQPGGSLRL SCAASGFTFS AYSMIWVRQA PGKGLEWVSY IRPSGGRTTY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARGG LLLWFRTLKS NYFDYWGQGT 120 LVTVSSASTK GPSVFPLAPS SKS 143 X69-C12 LC 15 QDIQMTQSPS SLSAFVGDRV TITCRASQPI DNYLNWYHQK PGKAPKLLIY AASRLQSGVP 60 SRLSGSGFGT DFTLTISSLQ PEDFGNYYCQ QSYTVPYTFG GGTKVEIR 108 X69-C12 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS AYSMIWVRQA PGKGLEWVSY IRPSGGRTTY 60 20 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARGG LLLWFRVLKS NYFDYWGQGT 120 LVTVSSASTK GPSVFPLAPS SKS 143 X69-E01 LC QDIQMTQSPS SLSAFVGDRV TITCRASQPI DNYLNWYHQK PGKAPKLLIY AASRLQSGVP 60 25 SRLSGSGFGT DFTLTISSLQ PEDFGNYYCQ QSYTVPYTFG GGTKVEIR 108 X69-E01 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS AYSMIWVRQA PGKGLEWVSY IRPSGGRTTY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARGG LLLWFRWLKS NYFDYWGQGT 120 30 LVTVSSASTK GPSVFPLAPS SKS 143 X69-H10 LC QDIQMTQSPS SLSAFVGDRV TITCRASQPI DNYLNWYHQK PGKAPKLLIY AASRLQSGVP 60 SRLSGSGFGT DFTLTISSLQ PEDFGNYYCQ QSYTVPYTFG GGTKVEIR 108 35 X69-H1O HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS AYSMIWVRQA PGKGLEWVSY IRPSGGRTTY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARGG LLLWFRYLKS NYFDYWGQGT 120 LVTVSSASTK GPSVFPLAPS SKS 143 40 X66-FO1 LC QDIQMTQSPS SLSAFVGDRV TITCRASQPI DNYLNWYHQK PGKAPKLLIY AASRLQSGVP 60 SRLSGSGFGT DFTLTISSLQ PEDFGNYYCQ QSYTVPYTFG GGTKVEIR 108 45 X66-FO1 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS AYSMIWVRQA PGKGLEWVSY IRPSGGRTTY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARGG LLLWFSELKS NYFDYWGQGT 120 LVTVSSASTK GPSVFPLAPS SKS 143 50 X66-Hll LC QDIQMTQSPS SLSAFVGDRV TITCRASQPI DNYLNWYHQK PGKAPKLLIY AASRLQSGVP 60 SRLSGSGFGT DFTLTISSLQ PEDFGNYYCQ QSYTVPYTFG GGTKVEIR 108 X66-H11 HC 55 EVQLLESGGG LVQPGGSLRL SCAASGFTFS AYSMIWVRQA PGKGLEWVSY IRPSGGRTTY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARGG LLLWFTELKS NYFDYWGQGT 120 100/151 LVTVSSASTK GPSVFPLAPS SKS 143 X66-C02 LC QDIQMTQSPS SLSAFVGDRV TITCRASQPI DNYLNWYHQK PGKAPKLLIY AASRLQSGVP 60 5 SRLSGSGFGT DFTLTISSLQ PEDFGNYYCQ QSYTVPYTFG GGTKVEIR 108 X66-C02 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS AYSMIWVRQA PGKGLEWVSY IRPSGGRTTY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARGG LLLWFVELKS NYFDYWGQGT 120 10 LVTVSSASTK GPSVFPLAPS SKS 143 X66-F09 LC QDIQMTQSPS SLSAFVGDRV TITCRASQPI DNYLNWYHQK PGKAPKLLIY AASRLQSGVP 60 SRLSGSGFGT DFTLTISSLQ PEDFGNYYCQ QSYTVPYTFG GGTKVEIR 108 15 X66-F09 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS AYSMIWVRQA PGKGLEWVSY IRPSGGRTTY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARGG LLLWFWELKS NYFDYWGQGT 120 LVTVSSASTK GPSVFPLAPS SKS 143 20 X66-G08 LC QDIQMTQSPS SLSAFVGDRV TITCRASQPI DNYLNWYHQK PGKAPKLLIY AASRLQSGVP 60 SRLSGSGFGT DFTLTISSLQ PEDFGNYYCQ QSYTVPYTFG GGTKVEIR 108 25 X66-G08 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS AYSMIWVRQA PGKGLEWVSY IRPSGGRTTY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARGG LLLWFYELKS NYFDYWGQGT 120 LVTVSSASTK GPSVFPLAPS SKS 143 30 X67-C09 LC QDIQMTQSPS SLSAFVGDRV TITCRASQPI DNYLNWYHQK PGKAPKLLIY AASRLQSGVP 60 SRLSGSGFGT DFTLTISSLQ PEDFGNYYCQ QSYTVPYTFG GGTKVEIR 108 X67-C09 HC 35 EVQLLESGGG LVQPGGSLRL SCAASGFTFS AYSMIWVRQA PGKGLEWVSY IRPSGGRTTY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARGG LLLWGRELKS NYFDYWGQGT 120 LVTVSSASTK GPSVFPLAPS SKS 143 X67-B04 LC 40 QDIQMTQSPS SLSAFVGDRV TITCRASQPI DNYLNWYHQK PGKAPKLLIY AASRLQSGVP 60 SRLSGSGFGT DFTLTISSLQ PEDFGNYYCQ QSYTVPYTFG GGTKVEIR 108 X67-B04 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS AYSMIWVRQA PGKGLEWVSY IRPSGGRTTY 60 45 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARGG LLLWKRELKS NYFDYWGQGT 120 LVTVSSASTK GPSVFPLAPS SKS 143 X67-GO9 LC QDIQMTQSPS SLSAFVGDRV TITCRASQPI DNYLNWYHQK PGKAPKLLIY AASRLQSGVP 60 50 SRLSGSGFGT DFTLTISSLQ PEDFGNYYCQ QSYTVPYTFG GGTKVEIR 108 X67-GO9 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS AYSMIWVRQA PGKGLEWVSY IRPSGGRTTY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARGG LLLWLRELKS NYFDYWGQGT 120 55 LVTVSSASTK GPSVFPLAPS SKS 143 101/151 X67-C03 LC QDIQMTQSPS SLSAFVGDRV TITCRASQPI DNYLNWYHQK PGKAPKLLIY AASRLQSGVP 60 SRLSGSGFGT DFTLTISSLQ PEDFGNYYCQ QSYTVPYTFG GGTKVEIR 108 5 X67-C03 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS AYSMIWVRQA PGKGLEWVSY IRPSGGRTTY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARGG LLLWMRELKS NYFDYWGQGT 120 LVTVSSASTK GPSVFPLAPS SKS 143 10 X67-DO3 LC QDIQMTQSPS SLSAFVGDRV TITCRASQPI DNYLNWYHQK PGKAPKLLIY AASRLQSGVP 60 SRLSGSGFGT DFTLTISSLQ PEDFGNYYCQ QSYTVPYTFG GGTKVEIR 108 X67-DO3 HC 15 EVQLLESGGG LVQPGGSLRL SCAASGFTFS AYSMIWVRQA PGKGLEWVSY IRPSGGRTTY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARGG LLLWNRELKS NYFDYWGQGT 120 LVTVSSASTK GPSVFPLAPS SKS 143 X67-B05 LC 20 QDIQMTQSPS SLSAFVGDRV TITCRASQPI DNYLNWYHQK PGKAPKLLIY AASRLQSGVP 60 SRLSGSGFGT DFTLTISSLQ PEDFGNYYCQ QSYTVPYTFG GGTKVEIR 108 X67-B05 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS AYSMIWVRQA PGKGLEWVSY IRPSGGRTTY 60 25 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARGG LLLWPRELKS NYFDYWGQGT 120 LVTVSSASTK GPSVFPLAPS SKS 143 X67-F01 LC QDIQMTQSPS SLSAFVGDRV TITCRASQPI DNYLNWYHQK PGKAPKLLIY AASRLQSGVP 60 30 SRLSGSGFGT DFTLTISSLQ PEDFGNYYCQ QSYTVPYTFG GGTKVEIR 108 X67-F01 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS AYSMIWVRQA PGKGLEWVSY IRPSGGRTTY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARGG LLLWQRELKS NYFDYWGQGT 120 35 LVTVSSASTK GPSVFPLAPS SKS 143 X67-G05 LC QDIQMTQSPS SLSAFVGDRV TITCRASQPI DNYLNWYHQK PGKAPKLLIY AASRLQSGVP 60 SRLSGSGFGT DFTLTISSLQ PEDFGNYYCQ QSYTVPYTFG GGTKVEIR 108 40 X67-G05 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS AYSMIWVRQA PGKGLEWVSY IRPSGGRTTY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARGG LLLWRRELKS NYFDYWGQGT 120 LVTVSSASTK GPSVFPLAPS SKS 143 45 X67-B03 LC QDIQMTQSPS SLSAFVGDRV TITCRASQPI DNYLNWYHQK PGKAPKLLIY AASRLQSGVP 60 SRLSGSGFGT DFTLTISSLQ PEDFGNYYCQ QSYTVPYTFG GGTKVEIR 108 50 X67-B03 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS AYSMIWVRQA PGKGLEWVSY IRPSGGRTTY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARGG LLLWSRELKS NYFDYWGQGT 120 LVTVSSASTK GPSVFPLAPS SKS 143 55 X67-F1O LC QDIQMTQSPS SLSAFVGDRV TITCRASQPI DNYLNWYHQK PGKAPKLLIY AASRLQSGVP 60 102/151 SRLSGSGFGT DFTLTISSLQ PEDFGNYYCQ QSYTVPYTFG GGTKVEIR 108 X67-F10 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS AYSMIWVRQA PGKGLEWVSY IRPSGGRTTY 60 5 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARGG LLLWTRELKS NYFDYWGQGT 120 LVTVSSASTK GPSVFPLAPS SKS 143 X67-H01 LC QDIQMTQSPS SLSAFVGDRV TITCRASQPI DNYLNWYHQK PGKAPKLLIY AASRLQSGVP 60 10 SRLSGSGFGT DFTLTISSLQ PEDFGNYYCQ QSYTVPYTFG GGTKVEIR 108 X67-H01 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS AYSMIWVRQA PGKGLEWVSY IRPSGGRTTY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARGG LLLWWRELKS NYFDYWGQGT 120 15 LVTVSSASTK GPSVFPLAPS SKS 143 X67-F08 LC QDIQMTQSPS SLSAFVGDRV TITCRASQPI DNYLNWYHQK PGKAPKLLIY AASRLQSGVP 60 SRLSGSGFGT DFTLTISSLQ PEDFGNYYCQ QSYTVPYTFG GGTKVEIR 108 20 X67-F08 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS AYSMIWVRQA PGKGLEWVSY IRPSGGRTTY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARGG LLLWYRELKS NYFDYWGQGT 120 LVTVSSASTK GPSVFPLAPS SKS 143 25 103/151 >-4 >-4 H H H U S u 00 0 SSSCCC U) v4 v4 040404040400 I I v I- >0 [-1 [-1 -H H4 H H H5 H5 G00 00 0 0 C4 > > p! Hc o CSo o 0 o o oCoCoCoCS nnIoo-o o of o oi , -CH H HH H H om c H *-HH HH H H HH H HHH 04 H H04-o oo N4 00 o 00 - 000000~ C- M F- H H- m H m H (n ne c o HHHHHHo - Z - O >0 k -r- p H H -H c HOH H 0 H00GHHNCNCS I I = I1 I 04/151 A ~~104/151 Amino acid sequences of light chain (LC) and heavy chain (HC) variable domain of affinity matured antibody inhibitors of pKal discovered using ROLIC are shown below. X59-C07 LC QDIQMTQSPS SLSASVGDRV TVTCRAGRSI STYVNWYQQK PGKAPKLLIY AASSLQSGVP 60 SRFSGSRSGT DFTLTISSLQ PEDFATYYCQ QSQSTPYTFG QGTKLEVK 108 X59-C07 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS HYLMTWVRQA PGKGLEWVSY ISPSGGHTIY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARVA RGIAARSRTS YFDYWGQGTL 120 VTVSSASTKG PSVFPLAPSS KS 142 X60-D01 LC QDIQMTQSPG TLSLSPGERA TLSCRASQIV SSRYLAWYQQ RPGQAPRLLI YGAASRATGI 60 PDRFSGSGSG TDFTLTISSL QAEDFATYYC QQTYSSPFTF GQGTKMEIK 109 X60-D01 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS HYLMTWVRQA PGKGLEWVSY ISPSGGHTIY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARVA RGIAARSRTS YFDYWGQGTL 120 VTVSSASTKG PSVFPLAPSS KS 142 X63-G06 LC (Fab version of X81-B01 IgG) QDIQMTQSPG TLSLSPGERA TLSCRTSQFV NSNYLAWYQQ TPGQAPRLLI YGASSRATGI 60 PDRFSGTGYG TDFTLTISRL EPEDYGTYYC QQSSRTPWTF GQGTRVEIK 109 X63-G06 HC (Fab version of X81-B01 IgG) EVQLLESGGG LVQPGGSLRL SCAASGFTFS HYLMTWVRQA PGKGLEWVSY ISPSGGHTIY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARVA RGIAARSRTS YFDYWGQGTL 120 VTVSSASTKG PSVFPLAPSS KS 142 X63-G10 LC QDIQMTQSPD SLSASVGDRV TITCRASQSI SNYLNWYQQK PGKAPKLLIY AASSLQSGVP 60 SRFSGSGSGT DFTLTISGLQ PEDFASYYCQ QSYTSPYTFV QGTKLEIKRT 110 X63-G10 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS HYLMTWVRQA PGKGLEWVSY ISPSGGHTIY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARVA RGIAARSRTS YFDYWGQGTL 120 VTVSSASTKG PSVFPLAPSS KS 142 X64-F04 LC QDIQMTQSPA TLSLSPGERA TLSCRASQIV SSNYLAWYQQ KPGQAPRLLI YGASNRATGI 60 PDRFSGSGSG TEFTLTISSL QSEDFAIYYC QQSFNIPYTF GQGTRVDIK 109 X64-F04 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS HYLMTWVRQA PGKGLEWVSY ISPSGGHTIY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARVA RGIAARSRTS YFDYWGQGTL 120 VTVSSASTKG PSVFPLAPSS KS 142 X81-BO1 is the IgG version of the X63-G06 Fab, as indicated above. Example 6: Affinity Maturation In addition to optimizing the sequence of the clipped antibody (M142-H08), we 105/151 also performed affinity maturation on two of the antibodies identified by phage display (M162-A04 and M160-G12). Both of these antibodies inhibit human pKal with single digit nanomolar potency, appear specific to pKal, and do not bind prekallikrein (Table 7). We first performed a novel form of light chain shuffling called ROLIC (Rapid Qptimization of Light Chains) on M162-A04 and M160-G12 (see, e.g., WO 2009/102927 and U.S. 2009-0215119). From the screening of the antibodies discovered by ROLIC we identified one antibody with subnamolar potency (X63-G06) that shared the same heavy chain as M160-G12. We then constructed HV-CDR3 spiking affinity maturation libraries based on CDR3 sequences in M162-A04 and X63-G06 (described below). Affinity Maturation by ROLIC. We used ROLIC to affinity mature the two leads from Table 7 that were not cleaved (M162-A04 and M160-G12). This process identified one antibody that inhibits pKal with a subnanomolar Ki,app (Table 11). X63 G06 inhibits pKal with a Ki,app of approximately 0.4 nM as a Fab fragment. When this antibody was converted to an IgG that is germlined and sequenced optimized for CHO cell expression (X81-BO1) it was found to inhibit pKal with a Ki,app of approximately 0.2 nM. Example 7: Affinity Maturation of Heavy Chain CDR1/2 and CDR3 We used two additional affinity maturation strategies to identify highly potent antibodies based on two different parental antibody inhibitor leads: M162-A04 and X63 G06. One approach was to generate libraries that shuffled the CDR1/2 of the HC of two different parental antibody inhibitor leads (M162-A04 and X63-G06) against additional CDR1/2 diversity. Another approach was to create heavy chain CDR3 spiking libraries based on these leads. The 82 antibodies that were discovered based on improvements in M162-A04 due to modifications in either the CDR1/2 and CDR3 region are shown in Table 12. Inhibition screening with 10 nM antibody (as Fab fragments) revealed that there were 33 antibodies that inhibited pKal activity by over 90%. Several antibodies were shown to be subnanomolar inhibitors of human pKal. The 62 antibodies that were discovered based on improvements in X63-G06 due to modifications in either the CDR1/2 and CDR3 region are shown in Table 13. 106/151 Inhibition screening with 10 nM antibody (as Fab fragments) revealed that there were 24 antibodies that inhibited pKal activity by over 90%. Several antibodies were shown to be subnanomolar inhibitors of human pKal. 107/151 09 s H H nj n H cnn nM M Cs M M Cs M CuI H H H H H H H H H H H H H H H H H > 8 H>> Z > > > > HF-A> Z H v o H H H H H H H H H H H H H H H H H 04 4 000000000000000 -I H H H H H H H H H H H HO > H H H H H H H H H H H H H H H H H 1 H H H H H H H H H H H H H H H H H 0 H H H H H H H H H H H H H H H H H >G 000 N 1C2S CS C S C S S C C CS CS, CS CS C Ci H H H H H H H H H H H H H H H H H 0 Q0 mS wS CS Q0 mS mS mS mS C S CD CD NS w I C CS) C) CS) C) CS) C) CS) C) CS) C) CS) C) CS CS CS CS) 0 C F 2 FZ 2 0 4 2 2 2 2 2 o oooooooo o o oo o o o mo oiod o o o o Lo ?totoo nottov p CD m m m - A mK CD CD) > - D m m 0 0 m m I o o o o o o o o o o o o o o o *rI L(N eK m T ( m o (N -A > (NO m o 0 > K > Cu e o o o a108 15 o1 e o o e H H H H H H H H H H H H4H H H H H H H H H H 4 H4 n n n n n n n n n n n Q n n n nn n r Q n n n n H H H H H H H H H H~ H H H H H H H H~ H H H H H H Z04Z C) CL C) CL CL CL CL CL C) C) CL C) CLI CLI CL) C) C C CL CL) C C mo o C o I- o o I- I o C o o e O I- >- w , N >-O w w CD H H H H H H H H H H H H H H H H H H H H H 9 H H H- >- > >- >- Z- >-H >- >- > >- - - - > -1-1 >-1 - > -1 >-O H>-1 > > H H H H H H H H H H H H H H H H H H H H H H H H >-S >- >- >- > - A - >- >- >- >- >- >-1 >- >- >- >- >- >-A >-A >- >-A H- >- > HOH H>H H H H OH HOH H H H0H H H H H H HSH H H >-H >- >-1 >-1 >- >- >- H- H- >-1 H- >- >-1 >-1 >- H- >- >-1 >-1 >-H >- H- >- H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H CS C S CS S CS S CS S CS S CS S CS S CS S CS S CS S CS CS C nj o no o no o no o no o no o no o no o no o no no no no o LO r-I r-I O O o vo o LO vM vM vm L vo [ M r-I vo vM [ r-I vo vT H H H H H H H H H H H H- H- H H H H H H H H LH LH H S C CS S CS S CS S CS S CS S CS S CS CS o oS oS oS oS o o o o vo vM O N T r-I r-I r-I vQ vo v vo v vM v N r-I vM v [s vN [s OS OS OS r-I r-I O r-I O r-I O O OS OS r-I OS O O O O r-I O O O O CS CS C S S r-r- S r-r- S CS S r-r- CS C r-r- CS 4 4 S CS 4 CS CS C IA IA IA IA IA IA IA IA IA IA IA IA I I I I I I I I I I I I oS oS CS o [S oS [S [S oS CS o oS S LS [S S CS CS C L C C O r-I r-I r- C' 0- r-I r- r- -AI - dN r- rI O r-I r-I r-I r- N C r-I r- r-IN > o o 0 -A -A 0 -A 0 -A 0 0 09/151 0 0 -A 0 0 H H H4H H Z H4 HH Z H H 4 4 4 4 4 4 H H - FZ H - H H H H H H H H H H H Z H - H - H - H H H H co CD co co co co co co co co co co co co co co co co co co co co co co H m H m > H H H m m m H m H H H m m m < m m H H H H H H H H HS H H H H H H H H H H H H H H H H 0 00 4 4 4 D D CO 00 000 0 00 0 00 CD0Z 0 5 CD0 H H H H H H H H H H H H H H H H H H H H H H H H o oo O o 00000 00000o o0 o0 H HS HOH H H H H H H H HS 0 H H H HS HS H H H HOH H Q0 N O LO m 11 11 N M O - M N O o N m w N CD N N 0- C ) 0 >) CS) 0 0 0 0-) 1 CS) H- CS) H- C ) 0 0 0 C- 0- C S CS) 0 o o o C-) o o o o o oo o o o o o LO m C-) VA G OA Z > VA V VA [ u LO H r-I H LO A CS 1 M LZ C A r-I ) m LZ L) ) r-) Z Z G m m m G O m r- r H H- H H H H H H H H H H H H H H H H H r H H r 110/151 CD ZD CD C D CD C C D D C CD CD CD CD H H H H H H H H H H H H H H H CS H 00 0 000 0 00 0 04 H lHHHH H H H H H H H H H H H H H H H H H H H H H H H Z H H H HZ A 0> H H H HA H-A HA HA H O OO OOOOOO 0 0 O 0 0 O o LO LO LO LO LO LO LOOOOOOO CS CS C S S C S DS CD CD CD C C CS CS CD m CS CS WS C CD m4 WS m Z m C C D m 4 CS oo Po o o o o N o o - o o o N oIo o H H H H H H H H>H HOH H H H H H H H H H H H H H H H H H H H H H H H G GGZ Z m Z Z Z Z VA HZG Z HG m H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H Ho z z z z z z z z z z z z z z z z z H H H H H H H H H H H H H H H H H CS CS O O OS CS O CS CS O O CS O S CS CS O j O nG n2 4 4~ n~ G n~ 2 n2 n~ < < G n < vI I I~ I~ I~ I~ I~ I~ I~ I~ I I I I I I I H H H H H H H H H H H H H H H H H CS CS CS C C CS C CS C CS C C CO CO CS C C vM M vM M vN M vN M vM N vM M vN a vM vN v CS S CS S CS S CS S CS S CS S CS S CS CS C CS C CS S CS CS C CS S CS CS C CS111/151 C Amino acid sequences of light chain (LC) and heavy chain (HC) variable domain of pKal antibodies obtained from CDR1/2 and CDR3 spiking affinity maturation libraries based on M162-A04. M195-A02 LC QDIQMTQSPS TLSASVGDRV TITCRASQSI SSWLAWYQQK PGKAPNLLIY KASTLESGVP 60 SRFSGSGSGT EFTLTISSLQ PDDFATYYCQ QYNTYWTFGQ GTKVEIK 107 M195-A02 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS QYMMMWVRQA PGKGLEWVSG ISSSGGHTDY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCAYRR TGIPRRDAFD IWGQGTMVTV 120 SSASTKGPSV FPLAPSSKS 139 M195-A12 LC QDIQMTQSPS TLSASVGDRV TITCRASQSI SSWLAWYQQK PGKAPNLLIY KASTLESGVP 60 SRFSGSGSGT EFTLTISSLQ PDDFATYYCQ QYNTYWTFGQ GTKVEIK 107 M195-A12 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS PYMMMWVRQA PGKGLEWVSG IYPSGGYTVY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCAYRR TGIPRRDAFD IWGQGTMVTV 120 SSASTKGPSV FPLAPSSKS 139 M195-B02 LC QDIQMTQSPS TLSASVGDRV TITCRASQSI SSWLAWYQQK PGKAPNLLIY KASTLESGVP 60 SRFSGSGSGT EFTLTISSLQ PDDFATYYCQ QYNTYWTFGQ GTKVEIK 107 M195-B02 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS PYLMWWVRQA PGKGLEWVSY IGPSGGPTHY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCAYRR TGIPRRDAFD IWGQGTMVTV 120 SSASTKGPSV FPLAPSSKS 139 M195-B12 LC QDIQMTQSPS TLSASVGDRV TITCRASQSI SSWLAWYQQK PGKAPNLLIY KASTLESGVP 60 SRFSGSGSGT EFTLTISSLQ PDDFATYYCQ QYNTYWTFGQ GTKVEIK 107 M195-B12 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS KYWMYWVRQA PGKGLEWVSY IRPSGGQTYY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCAYRR TGIPRRDAFD IWGQGTMVTV 120 SSASTKGPSV FPLAPSSKS 139 M195-C12 LC QDIQMTQSPS TLSASVGDRV TITCRASQSI SSWLAWYQQK PGKAPNLLIY KASTLESGVP 60 SRFSGSGSGT EFTLTISSLQ PDDFATYYCQ QYNTYWTFGQ GTKVEIK 107 M195-C12 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS MYQMFWVRQA PGKGLEWVSS ISPGGGTQYA 60 DSVKGRFTIS RDNSKNTLYL QMNSLRAEDT AVYYCAYRRT GIPRRDAFDI WGQGTMVTVS 120 SASTKGPSVF PLAPSSKS 138 M195-D12 LC QDIQMTQSPS TLSASVGDRV TITCRASQSI SSWLAWYQQK PGKAPNLLIY KASTLESGVP 60 SRFSGSGSGT EFTLTISSLQ PDDFATYYCQ QYNTYWTFGQ GTKVEIK 107 M195-D12 HC 112/151 EVQLLESGGG LVQPGGSLRL SCAASGFTFS IYGMFWVRQA PGKGLEWVSG IGPSGGPTKY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCAYRR TGIPRRDAFD IWGQGTMVTV 120 SSASTKGPSV FPLAPSSKS 139 M195-E12 LC QDIQMTQSPS TLSASVGDRV TITCRASQSI SSWLAWYQQK PGKAPNLLIY KASTLESGVP 60 SRFSGSGSGT EFTLTISSLQ PDDFATYYCQ QYNTYWTFGQ GTKVEIK 107 M195-E12 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS YYIMFWVRQA PGKGLEWVSY ISPSGGYTHY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCAYRR TGIPRRDAFD IWGQGTMVTV 120 SSASTKGPSV FPLAPSSKS 139 M195-F12 LC QDIQMTQSPS TLSASVGDRV TITCRASQSI SSWLAWYQQK PGKAPNLLIY KASTLESGVP 60 SRFSGSGSGT EFTLTISSLQ PDDFATYYCQ QYNTYWTFGQ GTKVEIK 107 M195-F12 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS HYVMMWVRQA PGKGLEWVSY IVPSGGVTAY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCAYRR TGIPRRDAFD IWGQGTMVTV 120 SSASTKGPSV FPLAPSSKS 139 M0195-G02 LC QDIQMTQSPS TLSASVGDRV TITCRASQSI SSWLAWYQQK PGKAPNLLIY KASTLESGVP 60 SRFSGSGSGT EFTLTISSLQ PDDFATYYCQ QYNTYWTFGQ GTKVEIK 107 M195-G02 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS PYNMMWVRQA PGKGLEWVSS IWPSGGTTDY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCAYRR TGIPRRDAFD IWGQGTMVTV 120 SSASTKGPSV FPLAPSSKS 139 M196-C06 LC QDIQMTQSPS TLSASVGDRV TITCRASQSI SSWLAWYQQK PGKAPNLLIY KASTLESGVP 60 SRFSGSGSGT EFTLTISSLQ PDDFATYYCQ QYNTYWTFGQ GTKVEIK 107 M196-C06 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS IYSMHWVRQA PGKGLEWVSS IYPSRGMTWY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCAYRR TGIPRRDAFD IWGQGTMVTV 120 SSASTKGPSV FPLAPSSKS 139 M196-D02 LC QDIQMTQSPS TLSASVGDRV TITCRASQSI SSWLAWYQQK PGKAPNLLIY KASTLESGVP 60 SRFSGSGSGT EFTLTISSLQ PDDFATYYCQ QYNTYWTFGQ GTKVEIK 107 M196-D02 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS VYSMHWVRQA PGKGLEWVSV IGPSGGITLY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCAYRR TGIPRRDAFD IWGQGTMVTV 120 SSASTKGPSV FPLAPSSKS 139 M196-D12 LC QDIQMTQSPS TLSASVGDRV TITCRASQSI SSWLAWYQQK PGKAPNLLIY KASTLESGVP 60 SRFSGSGSGT EFTLTISSLQ PDDFATYYCQ QYNTYWTFGQ GTKVEIK 107 M196-D12 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS RYSMRWVRQA PGKGLEWVSV IYPSGGQTYY 60 113/151 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCAYRR TGIPRRDAFD IWGQGTMVTV 120 SSASTKGPSV FPLAPSSKS 139 M196-G12 LC QDIQMTQSPS TLSASVGDRV TITCRASQSI SSWLAWYQQK PGKAPNLLIY KASTLESGVP 60 SRFSGSGSGT EFTLTISSLQ PDDFATYYCQ QYNTYWTFGQ GTKVEIK 107 M196-G12 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS NYSMDWVRQA PGKGLEWVSR IYSSGGGTIY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCAYRR TGIPRRDAFD IWGQGTMVTV 120 SSASTKGPSV FPLAPSSKS 139 M196-H03 LC QDIQMTQSPS TLSASVGDRV TITCRASQSI SSWLAWYQQK PGKAPNLLIY KASTLESGVP 60 SRFSGSGSGT EFTLTISSLQ PDDFATYYCQ QYNTYWTFGQ GTKVEIK 107 M196-H03 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS RYVMWWVRQA PGKGLEWVSS ISPSGDTHYA 60 DSVKGRFTIS RDNSKNTLYL QMNSLRAEDT AVYYCAYRRT GIPRRDAFDI WGQGTMVTVS 120 SASTKGPSVF PLAPSSKS 138 M197-A01 LC QDIQMTQSPS TLSASVGDRV TITCRASQSI SSWLAWYQQK PGKAPNLLIY KASTLESGVP 60 SRFSGSGSGT EFTLTISSLQ PDDFATYYCQ QYNTYWTFGQ GTKVEIK 107 M197-A01 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS IYDMIWVRQA PGKGLEWVSS IYPSGGNTSY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCAYRR TGIPRRDAFD IWGQGTMVTV 120 SSASTKGPSV FPLAPSSKS 139 M197-A08 LC QDIQMTQSPS TLSASVGDRV TITCRASQSI SSWLAWYQQK PGKAPNLLIY KASTLESGVP 60 SRFSGSGSGT EFTLTISSLQ PDDFATYYCQ QYNTYWTFGQ GTKVEIK 107 M197-A08 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS IYSMQWVRQA PGKGLEWVSS IGSSGGKTLY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCAYRR TGIPRRDAFD IWGQGTMVTV 120 SSASTKGPSV FPLAPSSKS 139 M197-A09 LC QDIQMTQSPS TLSASVGDRV TITCRASQSI SSWLAWYQQK PGKAPNLLIY KASTLESGVP 60 SRFSGSGSGT EFTLTISSLQ PDDFATYYCQ QYNTYWTFGQ GTKVEIK 107 M197-A09 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS VYNMHWVRQA PGKGLEWVSS IYPSGGMTTY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCAYRR TGIPRRDAFD IWGQGTMVTV 120 SSASTKGPSV FPLAPSSKS 139 M197-C12 LC QDIQMTQSPS TLSASVGDRV TITCRASQSI SSWLAWYQQK PGKAPNLLIY KASTLESGVP 60 SRFSGSGSGT EFTLTISSLQ PDDFATYYCQ QYNTYWTFGQ GTKVEIK 107 M197-C12 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS PYDMLWVRQA PGKGLEWVSY IVSSGGLTKY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCAYRR TGIPRRDAFD IWGQGTMVTV 120 SSASTKGPSV FPLAPSSKS 139 114/151 M197-E12 LC QDIQMTQSPS TLSASVGDRV TITCRASQSI SSWLAWYQQK PGKAPNLLIY KASTLESGVP 60 SRFSGSGSGT EFTLTISSLQ PDDFATYYCQ QYNTYWTFGQ GTKVEIK 107 M197-E12 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS TYTMRWVRQA PGKGLEWVSS IYPSGGKTQY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCAYRR TGIPRRDAFD IWGQGTMVTV 120 SSASTKGPSV FPLAPSSKS 139 M197-F01 LC QDIQMTQSPS TLSASVGDRV TITCRASQSI SSWLAWYQQK PGKAPNLLIY KASTLESGVP 60 SRFSGSGSGT EFTLTISSLQ PDDFATYYCQ QYNTYWTFGQ GTKVEIK 107 M197-F01 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS IYHMYWVRQA PGKGLEWVSS IGPSGGPTGY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCAYRR TGIPRRDAFD IWGQGTMVTV 120 SSASTKGPSV FPLAPSSKS 139 M197-F03 LC QDIQMTQSPS TLSASVGDRV TITCRASQSI SSWLAWYQQK PGKAPNLLIY KASTLESGVP 60 SRFSGSGSGT EFTLTISSLQ PDDFATYYCQ QYNTYWTFGQ GTKVEIK 107 M197-F03 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS IYSMFWVRQA PGKGLEWVSS IGPSGGVTHY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCAYRR TGIPRRDAFD IWGQGTMVTV 120 SSASTKGPSV FPLAPSSKS 139 M197-G10 LC QDIQMTQSPS TLSASVGDRV TITCRASQSI SSWLAWYQQK PGKAPNLLIY KASTLESGVP 60 SRFSGSGSGT EFTLTISSLQ PDDFATYYCQ QYNTYWTFGQ GTKVEIK 107 M197-G1O HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS VYAMRWVRQA PGKGLEWVSS IYPSGGKTWY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCAYRR TGIPRRDAFD IWGQGTMVTV 120 SSASTKGPSV FPLAPSSKS 139 M197-Gll LC QDIQMTQSPS TLSASVGDRV TITCRASQSI SSWLAWYQQK PGKAPNLLIY KASTLESGVP 60 SRFSGSGSGT EFTLTISSLQ PDDFATYYCQ QYNTYWTFGQ GTKVEIK 107 M197-Gll HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS TYAMVWVRQA PGKGLEWVSS IYPSGGITTY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCAYRR TGIPRRDAFD IWGQGTMVTV 120 SSASTKGPSV FPLAPSSKS 139 M197-H1O LC QDIQMTQSPS TLSASVGDRV TITCRASQSI SSWLAWYQQK PGKAPNLLIY KASTLESGVP 60 SRFSGSGSGT EFTLTISSLQ PDDFATYYCQ QYNTYWTFGQ GTKVEIK 107 M197-H1O HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS SYNMHWVRQA PGKGLEWVSS IVPSGGKTNY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCAYRR TGIPRRDAFD IWGQGTMVTV 120 SSASTKGPSV FPLAPSSKS 139 115/151 M197-Hll LC QDIQMTQSPS TLSASVGDRV TITCRASQSI SSWLAWYQQK PGKAPNLLIY KASTLESGVP 60 SRFSGSGSGT EFTLTISSLQ PDDFATYYCQ QYNTYWTFGQ GTKVEIK 107 M197-Hll HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS IYNMIWVRQA PGKGLEWVSS IYPSGGWTTY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCAYRR TGIPRRDAFD IWGQGTMVTV 120 SSASTKGPSV FPLAPSSKS 139 M198-A01 LC QDIQMTQSPS TLSASVGDRV TITCRASQSI SSWLAWYQQK PGKAPNLLIY KASTLESGVP 60 SRFSGSGSGT EFTLTISSLQ PDDFATYYCQ QYNTYWTFGQ GTKVEIK 107 M198-A01 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS PYTMIWVRQA PGKGLEWVSS ISSSGGMTPY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCAYRR TGIPRRDAFD IWGQGTMVTV 120 SSASTKGPSV FPLAPSSKS 139 M198-A02 LC QDIQMTQSPS TLSASVGDRV TITCRASQSI SSWLAWYQQK PGKAPNLLIY KASTLESGVP 60 SRFSGSGSGT EFTLTISSLQ PDDFATYYCQ QYNTYWTFGQ GTKVEIK 107 M198-A02 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS RYSMIWVRQA PGKGLEWVSS IWSSGGATEY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCAYRR TGIPRRDAFD IWGQGTMVTV 120 SSASTKGPSV FPLAPSSKS 139 M198-A06 LC QDIQMTQSPS TLSASVGDRV TITCRASQSI SSWLAWYQQK PGKAPNLLIY KASTLESGVP 60 SRFSGSGSGT EFTLTISSLQ PDDFATYYCQ QYNTYWTFGQ GTKVEIK 107 M198-A06 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS IYSMHWVRQA PGKGLEWVSS IYSSGGPTKY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCAYRR TGIPRRDAFD IWGQGTMVTV 120 SSASTKGPSV FPLAPSSKS 139 M198-A07 LC QDIQMTQSPS TLSASVGDRV TITCRASQSI SSWLAWYQQK PGKAPNLLIY KASTLESGVP 60 SRFSGSGSGT EFTLTISSLQ PDDFATYYCQ QYNTYWTFGQ GTKVEIK 107 M198-A07 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS RYQMHWVRQA PGKGLEWVSW ISPSGGITGY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCAYRR TGIPRRDAFD IWGQGTMVTV 120 SSASTKGPSV FPLAPSSKS 139 M198-A08 LC QDIQMTQSPS TLSASVGDRV TITCRASQSI SSWLAWYQQK PGKAPNLLIY KASTLESGVP 60 SRFSGSGSGT EFTLTISSLQ PDDFATYYCQ QYNTYWTFGQ GTKVEIK 107 M198-A08 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS WYMMQWVRQA PGKGLEWVSR ISPSGGTTYA 60 DSVKGRFTIS RDNSKNTLYL QMNSLRAEDT AVYYCAYRRT GIPRRDAFDI WGQGTMVTVS 120 SASTKGPSVF PLAPSSKS 138 M198-A09 LC QDIQMTQSPS TLSASVGDRV TITCRASQSI SSWLAWYQQK PGKAPNLLIY KASTLESGVP 60 SRFSGSGSGT EFTLTISSLQ PDDFATYYCQ QYNTYWTFGQ GTKVEIK 107 116/151 M198-A09 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS IYFMSWVRQA PGKGLEWVSS IRSSGGPTWY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCAYRR TGIPRRDAFD IWGQGTMVTV 120 SSASTKGPSV FPLAPSSKS 139 M198-B09 LC QDIQMTQSPS TLSASVGDRV TITCRASQSI SSWLAWYQQK PGKAPNLLIY KASTLESGVP 60 SRFSGSGSGT EFTLTISSLQ PDDFATYYCQ QYNTYWTFGQ GTKVEIK 107 M198-B09 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS VYSMTWVRQA PGKGLEWVSS IGSSGGSTTY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCAYRR TGIPRRDAFD IWGQGTMVTV 120 SSASTKGPSV FPLAPSSKS 139 M198-B12 LC QDIQMTQSPS TLSASVGDRV TITCRASQSI SSWLAWYQQK PGKAPNLLIY KASTLESGVP 60 SRFSGSGSGT EFTLTISSLQ PDDFATYYCQ QYNTYWTFGQ GTKVEIK 107 M198-B12 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS KYSMAWVRQA PGKGLEWVSG IYPSGGRTLY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCAYRR TGIPRRDAFD IWGQGTMVTV 120 SSASTKGPSV FPLAPSSKS 139 M198-C03 LC QDIQMTQSPS TLSASVGDRV TITCRASQSI SSWLAWYQQK PGKAPNLLIY KASTLESGVP 60 SRFSGSGSGT EFTLTISSLQ PDDFATYYCQ QYNTYWTFGQ GTKVEIK 107 M198-C03 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS RYSMSWVRQA PGKGLEWVSG ISPSGGETSY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCAYRR TGIPRRDAFD IWGQGTMVTV 120 SSASTKGPSV FPLAPSSKS 139 M198-C05 LC QDIQMTQSPS TLSASVGDRV TITCRASQSI SSWLAWYQQK PGKAPNLLIY KASTLESGVP 60 SRFSGSGSGT EFTLTISSLQ PDDFATYYCQ QYNTYWTFGQ GTKVEIK 107 M198-C05 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS RYKMYWVRQA PGKGLEWVSV IGPSGGATFY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCAYRR TGIPRRDAFD IWGQGTMVTV 120 SSASTKGPSV FPLAPSSKS 139 M198-C06 LC QDIQMTQSPS TLSASVGDRV TITCRASQSI SSWLAWYQQK PGKAPNLLIY KASTLESGVP 60 SRFSGSGSGT EFTLTISSLQ PDDFATYYCQ QYNTYWTFGQ GTKVEIK 107 M198-C06 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS QYFMHWVRQA PGKGLEWVSY IYPSGGMTEY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCAYRR TGIPRRDAFD IWGQGTMVTV 120 SSASTKGPSV FPLAPSSKS 139 M198-C09 LC QDIQMTQSPS TLSASVGDRV TITCRASQSI SSWLAWYQQK PGKAPNLLIY KASTLESGVP 60 SRFSGSGSGT EFTLTISSLQ PDDFATYYCQ QYNTYWTFGQ GTKVEIK 107 M198-C09 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS IYTMYWVRQA PGKGLEWVSS ISPSGGWTYY 60 117/151 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCAYRR TGIPRRDAFD IWGQGTMVTV 120 SSASTKGPSV FPLAPSSKS 139 M198-C10 LC QDIQMTQSPS TLSASVGDRV TITCRASQSI SSWLAWYQQK PGKAPNLLIY KASTLESGVP 60 SRFSGSGSGT EFTLTISSLQ PDDFATYYCQ QYNTYWTFGQ GTKVEIK 107 M198-C10 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS HYMGMNWVRQ APGKGLEWVS SIVPSGGWTQ 60 YADSVKGRFT ISRDNSKNTL YLQMNSLRAE DTAVYYCAYR RTGIPRRDAF DIWGQGTMVT 120 VSSASTKGPS VFPLAPSSKS 140 M198-D12 LC QDIQMTQSPS TLSASVGDRV TITCRASQSI SSWLAWYQQK PGKAPNLLIY KASTLESGVP 60 SRFSGSGSGT EFTLTISSLQ PDDFATYYCQ QYNTYWTFGQ GTKVEIK 107 M198-D12 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS LYVMYWVRQA PGKGLEWVSY IVPSGGPTAY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCAYRR TGIPRRDAFD IWGQGTMVTV 120 SSASTKGPSV FPLAPSSKS 139 M198-E02 LC QDIQMTQSPS TLSASVGDRV TITCRASQSI SSWLAWYQQK PGKAPNLLIY KASTLESGVP 60 SRFSGSGSGT EFTLTISSLQ PDDFATYYCQ QYNTYWTFGQ GTKVEIK 107 M198-E02 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS IYSMYWVRQA PGKGLEWVSY IRPSGGNTKY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCAYRR TGIPRRDAFD IWGQGTMVTV 120 SSASTKGPSV FPLAPSSKS 139 M198-E09 LC QDIQMTQSPS TLSASVGDRV TITCRASQSI SSWLAWYQQK PGKAPNLLIY KASTLESGVP 60 SRFSGSGSGT EFTLTISSLQ PDDFATYYCQ QYNTYWTFGQ GTKVEIK 107 M198-E09 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS IYDMNWVRQA PGKGLEWVSS IYPSGGRTRY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCAYRR TGIPRRDAFD IWGQGTMVTV 120 SSASTKGPSV FPLAPSSKS 139 M198-Ell LC QDIQMTQSPS TLSASVGDRV TITCRASQSI SSWLAWYQQK PGKAPNLLIY KASTLESGVP 60 SRFSGSGSGT EFTLTISSLQ PDDFATYYCQ QYNTYWTFGQ GTKVEIK 107 M198-Ell HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS TYSMYWVRQA PGKGLEWVSS IYPSGGLTWY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCAYRR TGIPRRDAFD IWGQGTMVTV 120 SSASTKGPSV FPLAPSSKS 139 M198-F04 LC QDIQMTQSPS TLSASVGDRV TITCRASQSI SSWLAWYQQK PGKAPNLLIY KASTLESGVP 60 SRFSGSGSGT EFTLTISSLQ PDDFATYYCQ QYNTYWTFGQ GTKVEIK 107 M198-F04 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS IYDMWWVRQA PGKGLEWVSS IRPSGGITKY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCAYRR TGIPRRDAFD IWGQGTMVTV 120 SSASTKGPSV FPLAPSSKS 139 118/151 M198-F08 LC QDIQMTQSPS TLSASVGDRV TITCRASQSI SSWLAWYQQK PGKAPNLLIY KASTLESGVP 60 SRFSGSGSGT EFTLTISSLQ PDDFATYYCQ QYNTYWTFGQ GTKVEIK 107 M198-F08 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS VYSMWWVRQA PGKGLEWVSS ISSSGGMTEY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCAYRR TGIPRRDAFD IWGQGTMVTV 120 SSASTKGPSV FPLAPSSKS 139 M198-F09 LC QDIQMTQSPS TLSASVGDRV TITCRASQSI SSWLAWYQQK PGKAPNLLIY KASTLESGVP 60 SRFSGSGSGT EFTLTISSLQ PDDFATYYCQ QYNTYWTFGQ GTKVEIK 107 M198-F09 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS VYNMHWVRQA PGKGLEWVSS IYPSGGMTYY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCAYRR TGIPRRDAFD IWGQGTMVTV 120 SSASTKGPSV FPLAPSSKS 139 M198-F12 LC QDIQMTQSPS TLSASVGDRV TITCRASQSI SSWLAWYQQK PGKAPNLLIY KASTLESGVP 60 SRFSGSGSGT EFTLTISSLQ PDDFATYYCQ QYNTYWTFGQ GTKVEIK 107 M198-F12 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS IYTMMWVRQA PGKGLEWVSS IWSSGGQTKY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCAYRR TGIPRRDAFD IWGQGTMVTV 120 SSASTKGPSV FPLAPSSKS 139 M198-G03 LC QDIQMTQSPS TLSASVGDRV TITCRASQSI SSWLAWYQQK PGKAPNLLIY KASTLESGVP 60 SRFSGSGSGT EFTLTISSLQ PDDFATYYCQ QYNTYWTFGQ GTKVEIK 107 M198-G03 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS QYTMVWVRQA PGKGLEWVSW IYSSRANYAD 60 SVKGRFTISR DNSKNTLYLQ MNSLRAEDTA VYYCAYRRTG IPRRDAFDIW GQGTMVTVSS 120 ASTKGPSVFP LAPSSKS 137 M198-G07 LC QDIQMTQSPS TLSASVGDRV TITCRASQSI SSWLAWYQQK PGKAPNLLIY KASTLESGVP 60 SRFSGSGSGT EFTLTISSLQ PDDFATYYCQ QYNTYWTFGQ GTKVEIK 107 M198-G07 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS IYDMTWVRQA PGKGLEWVSS IYPSGGQTIY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCAYRR TGIPRRDAFD IWGQGTMVTV 120 SSASTKGPSV FPLAPSSKS 139 M198-H02 LC QDIQMTQSPS TLSASVGDRV TITCRASQSI SSWLAWYQQK PGKAPNLLIY KASTLESGVP 60 SRFSGSGSGT EFTLTISSLQ PDDFATYYCQ QYNTYWTFGQ GTKVEIK 107 M198-H02 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS PYNMYWVRQA PGKGLEWVSW IVPGGVTKYA 60 DSVKGRFTIS RDNSKNTLYL QMNSLRAEDT AVYYCAYRRT GIPRRDAFDI WGQGTMVTVS 120 SASTKGPSVF PLAPSSKS 138 M198-H08 LC QDIQMTQSPS TLSASVGDRV TITCRASQSI SSWLAWYQQK PGKAPNLLIY KASTLESGVP 60 119/151 SRFSGSGSGT EFTLTISSLQ PDDFATYYCQ QYNTYWTFGQ GTKVEIK 107 M198-H08 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS IYDMYWVRQA PGKGLEWVSS IGPSGGPTAY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCAYRR TGIPRRDAFD IWGQGTMVTV 120 SSASTKGPSV FPLAPSSKS 139 M198-H09 LC QDIQMTQSPS TLSASVGDRV TITCRASQSI SSWLAWYQQK PGKAPNLLIY KASTLESGVP 60 SRFSGSGSGT EFTLTISSLQ PDDFATYYCQ QYNTYWTFGQ GTKVEIK 107 M198-H09 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS IYLMIWVRQA PGKGLEWVSY IGPSGGPTEY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCAYRR TGIPRRDAFD IWGQGTMVTV 120 SSASTKGPSV FPLAPSSKS 139 M199-A08 LC QDIQMTQSPS TLSASVGDRV TITCRASQSI SSWLAWYQQK PGKAPNLLIY KASTLESGVP 60 SRFSGSGSGT EFTLTISSLQ PDDFATYYCQ QYNTYWTFGQ GTKVEIK 107 M199-A08 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS HYIMMWVRQA PGKGLEWVSG IYSSGGITVY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCAYRR IGVPRRDEFD IWGQGTMVTV 120 SSASTKGPSV FPLAPSSKS 139 M199-All LC QDIQMTQSPS TLSASVGDRV TITCRASQSI SSWLAWYQQK PGKAPNLLIY KASTLESGVP 60 SRFSGSGSGT EFTLTISSLQ PDDFATYYCQ QYNTYWTFGQ GTKVEIK 107 M199-All HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS HYIMMWVRQA PGKGLEWVSG IYSSGGITVY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCAYRR RGIPRRDAFD IWGQGTMVTV 120 SSASTKGPSV FPLAPSSKS 139 M199-BO1 LC QDIQMTQSPS TLSASVGDRV TITCRASQSI SSWLAWYQQK PGKAPNLLIY KASTLESGVP 60 SRFSGSGSGT EFTLTISSLQ PDDFATYYCQ QYNTYWTFGQ GTKVEIK 107 M199-BO1 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS HYIMMWVRQA PGKGLEWVSG IYSSGGITVY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCAFRR TGIPRRDAFD NWGQGTMVTV 120 SSASTKGPSV FPLAPSSKS 139 M200-A1O LC QDIQMTQSPS TLSASVGDRV TITCRASQSI SSWLAWYQQK PGKAPNLLIY KASTLESGVP 60 SRFSGSGSGT EFTLTISSLQ PDDFATYYCQ QYNTYWTFGQ GTKVEIK 107 M200-A1O HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS HYIMMWVRQA PGKGLEWVSG IYSSGGITVY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCAYRR TGVPRRDSFD IWGQGTMVTV 120 SSASTKGPSV FPLAPSSKS 139 M200-BO1 LC QDIQMTQSPS TLSASVGDRV TITCRASQSI SSWLAWYQQK PGKAPNLLIY KASTLESGVP 60 SRFSGSGSGT EFTLTISSLQ PDDFATYYCQ QYNTYWTFGQ GTKVEIK 107 120/151 M200-BO1 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS HYIMMWVRQA PGKGLEWVSG IYSSGGITVY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCAYRR TGIPRRDAFD SWGQGTMVTV 120 SSASTKGPSV FPLAPSSKS 139 M200-DO3 LC QDIQMTQSPS TLSASVGDRV TITCRASQSI SSWLAWYQQK PGKAPNLLIY KASTLESGVP 60 SRFSGSGSGT EFTLTISSLQ PDDFATYYCQ QYNTYWTFGQ GTKVEIK 107 M200-DO3 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS HYIMMWVRQA PGKGLEWVSG IYSSGGITVY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCAWRR IGVPRRDSFD MWGQGTMVTV 120 SSASTKGPSV FPLAPSSKS 139 M200-Ell LC QDIQMTQSPS TLSASVGDRV TITCRASQSI SSWLAWYQQK PGKAPNLLIY KASTLESGVP 60 SRFSGSGSGT EFTLTISSLQ PDDFATYYCQ QYNTYWTFGQ GTKVEIK 107 M200-Ell HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS HYIMMWVRQA PGKGLEWVSG IYSSGGITVY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCAYRR TGVPRRDAFD NWGQGTMVTV 120 SSASTKGPSV FPLAPSSKS 139 M200-F01 LC QDIQMTQSPS TLSASVGDRV TITCRASQSI SSWLAWYQQK PGKAPNLLIY KASTLESGVP 60 SRFSGSGSGT EFTLTISSLQ PDDFATYYCQ QYNTYWTFGQ GTKVEIK 107 M200-F01 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS HYIMMWVRQA PGKGLEWVSG IYSSGGITVY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCAYRR MGIPRRNAFD IWGQGTMVTV 120 SSASTKGPSV FPLAPSSKS 139 M200-H07 LC QDIQMTQSPS TLSASVGDRV TITCRASQSI SSWLAWYQQK PGKAPNLLIY KASTLESGVP 60 SRFSGSGSGT EFTLTISSLQ PDDFATYYCQ QYNTYWTFGQ GTKVEIK 107 M200-H07 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS HYIMMWVRQA PGKGLEWVSG IYSSGGITVY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCAYRR TGVPRRNAFD NWGQGTMVTV 120 SSASTKGPSV FPLAPSSKS 139 M201-A06 LC QDIQMTQSPS TLSASVGDRV TITCRASQSI SSWLAWYQQK PGKAPNLLIY KASTLESGVP 60 SRFSGSGSGT EFTLTISSLQ PDDFATYYCQ QYNTYWTFGQ GTKVEIK 107 M201-A06 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS HYIMMWVRQA PGKGLEWVSG IYSSGGITVY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCAYRR TGIPRRDVFD IWGQGTMVTV 120 SSASTKGPSV FPLAPSSKS 139 M201-A07 LC QDIQMTQSPS TLSASVGDRV TITCRASQSI SSWLAWYQQK PGKAPNLLIY KASTLESGVP 60 SRFSGSGSGT EFTLTISSLQ PDDFATYYCQ QYNTYWTFGQ GTKVEIK 107 M201-A07 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS HYIMMWVRQA PGKGLEWVSG IYSSGGITVY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCAYRR TGVPRRDEFD IWGQGTMVTV 120 121/151 SSASTKGPSV FPLAPSSKS 139 M201-Fll LC QDIQMTQSPS TLSASVGDRV TITCRASQSI SSWLAWYQQK PGKAPNLLIY KASTLESGVP 60 SRFSGSGSGT EFTLTISSLQ PDDFATYYCQ QYNTYWTFGQ GTKVEIK 107 M201-Fll HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS HYIMMWVRQA PGKGLEWVSG IYSSGGITVY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCAYRR SGIPRRDAFD IWGQGTMVTV 120 SSASTKGPSV FPLAPSSKS 139 M201-H06 LC QDIQMTQSPS TLSASVGDRV TITCRASQSI SSWLAWYQQK PGKAPNLLIY KASTLESGVP 60 SRFSGSGSGT EFTLTISSLQ PDDFATYYCQ QYNTYWTFGQ GTKVEIK 107 M201-H06 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS HYIMMWVRQA PGKGLEWVSG IYSSGGITVY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCAYRR TGVPRRDAFD IWGQGTMVTV 120 SSASTKGPSV FPLAPSSKS 139 M201-H08 LC QDIQMTQSPS TLSASVGDRV TITCRASQSI SSWLAWYQQK PGKAPNLLIY KASTLESGVP 60 SRFSGSGSGT EFTLTISSLQ PDDFATYYCQ QYNTYWTFGQ GTKVEIK 107 M201-H08 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS HYIMMWVRQA PGKGLEWVSG IYSSGGITVY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCAYRR TGVPRRDALD NWGQGTMVTV 120 SSASTKGPSV FPLAPSSKS 139 M202-AO1 LC QDIQMTQSPS TLSASVGDRV TITCRASQSI SSWLAWYQQK PGKAPNLLIY KASTLESGVP 60 SRFSGSGSGT EFTLTISSLQ PDDFATYYCQ QYNTYWTFGQ GTKVEIK 107 M202-AO1 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS HYIMMWVRQA PGKGLEWVSG IYSSGGITVY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCAYRR IGVPRRDAFD IWGQGTMVTV 120 SSASTKGPSV FPLAPSSKS 139 M202-A04 LC QDIQMTQSPS TLSASVGDRV TITCRASQSI SSWLAWYQQK PGKAPNLLIY KASTLESGVP 60 SRFSGSGSGT EFTLTISSLQ PDDFATYYCQ QYNTYWTFGQ GTKVEIK 107 M202-A04 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS HYIMMWVRQA PGKGLEWVSG IYSSGGITVY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCAYRR KGIPRRDDFD IWGQGTMVTV 120 SSASTKGPSV FPLAPSSKS 139 M202-A08 LC QDIQMTQSPS TLSASVGDRV TITCRASQSI SSWLAWYQQK PGKAPNLLIY KASTLESGVP 60 SRFSGSGSGT EFTLTISSLQ PDDFATYYCQ QYNTYWTFGQ GTKVEIK 107 M202-A08 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS HYIMMWVRQA PGKGLEWVSG IYSSGGITVY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCAYRR TGIPRWDAFD IWGQGTMVTV 120 SSASTKGPSV FPLAPSSKS 139 M202-AlO LC 122/151 QDIQMTQSPS TLSASVGDRV TITCRASQSI SSWLAWYQQK PGKAPNLLIY KASTLESGVP 60 SRFSGSGSGT EFTLTISSLQ PDDFATYYCQ QYNTYWTFGQ GTKVEIK 107 M202-A10 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS HYIMMWVRQA PGKGLEWVSG IYSSGGITVY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCAFRR TGIPRRDSFD IWGQGTMVTV 120 SSASTKGPSV FPLAPSSKS 139 M202-A12 LC QDIQMTQSPS TLSASVGDRV TITCRASQSI SSWLAWYQQK PGKAPNLLIY KASTLESGVP 60 SRFSGSGSGT EFTLTISSLQ PDDFATYYCQ QYNTYWTFGQ GTKVEIK 107 M202-A12 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS HYIMMWVRQA PGKGLEWVSG IYSSGGITVY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCAYQR TGVPRRDSFN IWGQGTMVTV 120 SSASTKGPSV FPLAPSSKS 139 M202-B03 LC QDIQMTQSPS TLSASVGDRV TITCRASQSI SSWLAWYQQK PGKAPNLLIY KASTLESGVP 60 SRFSGSGSGT EFTLTISSLQ PDDFATYYCQ QYNTYWTFGQ GTKVEIK 107 M202-B03 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS HYIMMWVRQA PGKGLEWVSG IYSSGGITVY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCAYRR TGVPRRDDFD IWGQGTMVTV 120 SSASTKGPSV FPLAPSSKS 139 M202-B04 LC QDIQMTQSPS TLSASVGDRV TITCRASQSI SSWLAWYQQK PGKAPNLLIY KASTLESGVP 60 SRFSGSGSGT EFTLTISSLQ PDDFATYYCQ QYNTYWTFGQ GTKVEIK 107 M202-B04 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS HYIMMWVRQA PGKGLEWVSG IYSSGGITVY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCAYRR SGVPRRDDFD IWGQGTMVTV 120 SSASTKGPSV FPLAPSSKS 139 M202-C01 LC QDIQMTQSPS TLSASVGDRV TITCRASQSI SSWLAWYQQK PGKAPNLLIY KASTLESGVP 60 SRFSGSGSGT EFTLTISSLQ PDDFATYYCQ QYNTYWTFGQ GTKVEIK 107 M202-CO1 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS HYIMMWVRQA PGKGLEWVSG IYSSGGITVY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCAYRR TGVPRWDDFD IWGQGTMVTV 120 SSASTKGPSV FPLAPSSKS 139 M202-C02 LC QDIQMTQSPS TLSASVGDRV TITCRASQSI SSWLAWYQQK PGKAPNLLIY KASTLESGVP 60 SRFSGSGSGT EFTLTISSLQ PDDFATYYCQ QYNTYWTFGQ GTKVEIK 107 M202-C02 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS HYIMMWVRQA PGKGLEWVSG IYSSGGITVY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCAYRR PGVPRRDAFD IWGQGTMVTV 120 SSASTKGPSV FPLAPSSKS 139 M202-C09 LC QDIQMTQSPS TLSASVGDRV TITCRASQSI SSWLAWYQQK PGKAPNLLIY KASTLESGVP 60 SRFSGSGSGT EFTLTISSLQ PDDFATYYCQ QYNTYWTFGQ GTKVEIK 107 123/151 M202-C09 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS HYIMMWVRQA PGKGLEWVSG IYSSGGITVY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCAYRR IGVPRRDDFD IWGQGTMVTV 120 SSASTKGPSV FPLAPSSKS 139 M202-DO9 LC QDIQMTQSPS TLSASVGDRV TITCRASQSI SSWLAWYQQK PGKAPNLLIY KASTLESGVP 60 SRFSGSGSGT EFTLTISSLQ PDDFATYYCQ QYNTYWTFGQ GTKVEIK 107 M202-DO9 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS HYIMMWVRQA PGKGLEWVSG IYSSGGITVY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCAYRR IGVPRRDSFD IWGQGTMVTV 120 SSASTKGPSV FPLAPSSKS 139 M202-E03 LC QDIQMTQSPS TLSASVGDRV TITCRASQSI SSWLAWYQQK PGKAPNLLIY KASTLESGVP 60 SRFSGSGSGT EFTLTISSLQ PDDFATYYCQ QYNTYWTFGQ GTKVEIK 107 M202-E03 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS HYIMMWVRQA PGKGLEWVSG IYSSGGITVY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCAYRR TGIPRRDAFE IWGQGTMVTV 120 SSASTKGPSV FPLAPSSKS 139 M202-E06 LC QDIQMTQSPS TLSASVGDRV TITCRASQSI SSWLAWYQQK PGKAPNLLIY KASTLESGVP 60 SRFSGSGSGT EFTLTISSLQ PDDFATYYCQ QYNTYWTFGQ GTKVEIK 107 M202-E06 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS HYIMMWVRQA PGKGLEWVSG IYSSGGITVY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCAYRR RGVPRRDDFD IWGQGTMVTV 120 SSASTKGPSV FPLAPSSKS 139 M202-F06 LC QDIQMTQSPS TLSASVGDRV TITCRASQSI SSWLAWYQQK PGKAPNLLIY KASTLESGVP 60 SRFSGSGSGT EFTLTISSLQ PDDFATYYCQ QYNTYWTFGQ GTKVEIK 107 M202-F06 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS HYIMMWVRQA PGKGLEWVSG IYSSGGITVY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCAYRR TGVPRWDAFD IWGQGTMVTV 120 SSASTKGPSV FPLAPSSKS 139 M202-G03 LC QDIQMTQSPS TLSASVGDRV TITCRASQSI SSWLAWYQQK PGKAPNLLIY KASTLESGVP 60 SRFSGSGSGT EFTLTISSLQ PDDFATYYCQ QYNTYWTFGQ GTKVEIK 107 M202-G03 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS HYIMMWVRQA PGKGLEWVSG IYSSGGITVY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCAFRR TGVPRRDSFE IWGQGTMVTV 120 SSASTKGPSV FPLAPSSKS 139 M202-H03 LC QDIQMTQSPS TLSASVGDRV TITCRASQSI SSWLAWYQQK PGKAPNLLIY KASTLESGVP 60 SRFSGSGSGT EFTLTISSLQ PDDFATYYCQ QYNTYWTFGQ GTKVEIK 107 M202-H03 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS HYIMMWVRQA PGKGLEWVSG IYSSGGITVY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCAFRR TGVPRWDDFD IWGQGTMVTV 120 124/151 SSASTKGPSV FPLAPSSKS 139 M202-H05 LC QDIQMTQSPS TLSASVGDRV TITCRASQSI SSWLAWYQQK PGKAPNLLIY KASTLESGVP 60 SRFSGSGSGT EFTLTISSLQ PDDFATYYCQ QYNTYWTFGQ GTKVEIK 107 M202-H05 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS HYIMMWVRQA PGKGLEWVSG IYSSGGITVY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCAFRR TGVPRRDVFD IWGQGTMVTV 120 SSASTKGPSV FPLAPSSKS 139 125/151 01 >1 >H -H -H > >-1 H >- >- >H H H H >1 H H H C Hu H H H H H H 01 H H H H H H C S) FZ S CS CS CS C FZ FZ C FS C CS CS F C C F-A SH H H H H H H H H H H H H H H H H H C S CS CS CS CS CS CS CS CS CS CS CS CS CS CS CS CS C fl F-A F-A F-A F-A F-A F-A F-A F-A F-A F-A F-A F-A F-A F-A F-A F-A F-A F-A H HH HH H H C S4 C CD CS S CS S CS S CS CS C CD CD CD CD CD CD CD o H H H H H H H H H H H H H H H H H H 04 Q0 M N M N m) N m mmm Mm C-)S N Co >- oo o o o ovo o O H H H H H H H H H H H H H H H H H H - > o > > > m m -o >-1 C > >-N C C> C- C> C> C> C - -1 C >- C C C -1 C > SHH HH HH HHHHHHHH HH H k- CS o oo ko oo Co CS oCo m m o k CS o o o o m cu c) cS -A cS cS cS -A -A CS cS CD CD CD CD -A CD CD CD H H H H H H H H H H H H H H H H H H Z Z Z Z Z Z Z Z Z Z Z Z Z Z Z Z Z Z >H H H H H H H H H H H H H H H H H H . - 000 0 09 0 L0 0 0 0 L0 0 .C C 0 0 0 L0 L0TT T M M M M 9 0 9 O O mo o 0 ko o o oN o o o o o 0 o Ko o o dP o > o KO LC oC a e o' o' o' C' m' ' N (N (N (N o c 0aoao oaoo O H .0 | | | | | | | | | | | | | | | | | 1 -Cooro o o o ooH o1 o -A oN o 0 N a ko 0 o~ oN o K > -A 0 o 0 0 -A -A 0 - 0 0 A 0 -A260/105A1 H H El4 H 1 H H HHH H H 0 ZH HH H H 1H Z El4 H- H- >S 4 Eli H H H H H H H H H 01 H H H 0 H El4 01 CDD o co o co o co co o o > H o o o C4 C4S 0 CS CS4 CS CS4 CL CS4 CL C4 CS4 C4 CS4 C4 C4 C4 D4 C4 H4 D4 D4 CS 4 H H H H H H H H H H H H H H H Z H H H H H H H H C4 C4 C4 CS4 C4 CS4 C4 CS4 C4 D4 D4 D4 D4 D4 D4 D4 D4 C4 C4 C4 C4 C4 C4 C4 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 o o o o o oo o oo o oo o o o o o o oo o o oI Q0 C- I- N -1 -1 m N N -1 oo -1 N 0) N m LO M N C) o o o o o - o o Q0 m Q0 o oo O O o o) o) o) Q0 m O o CS ) C C CS) CS C) CS) C) CS) C) CS) C) CS) C) CS) CS C) CS) C) CS) C) CS) C) CS) H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H S CS S CS S CS S CS CS C > CS CS C > S CS S 0 CS CS C > CS H CS H H H H H H H CS H H E CS H H H H H CS H OH H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H H CS C S CS S CS S CS S CS S CS S CS S CS S CS S CS S CS CS C S CS S CS S CS S CS S CS S CS S CS S CS S CS S CS S CS CS C S CS S CS S CS S CS S CS S CS S CS S CS S CS S CS S CS CS C H H H H H H H H H H H H H H H H H H H H H H H H z z z z [S LS CS C S r-1 S LS CS S CS CS [ LS S LS CS S r-1 CS LS CS C L o o 0 0 > LC (N d a r-1 A m r-1 r-1C m m > r-1 o~ r-1 G C' -A K LC) M C' OC -A -A r- 0 0 0 O d > >- O KO KO r-1O LC r-1 C r-1 (N (N 0 0 -1 I I I I I I I I I I I I I I I I I I I I I I I I o LC) 0 [> 0 m Q d Q m LC LC) 0 dQ Q T d LC) m O 0 r- 0 r- 0 0 0 0 0 0 0 0 0 0 r- 0 0 0 0 0 0 0 0 (N (N (N (N (N (N (N (N (N (N (N (N (N (N (N (N (N (N (N (N (N (N (N (N 127/151 H H H H H H H oi H H H H oHo H H H o o o H H HH H H 01 H H H H c H H H H HH H H co ~ ~ coc oco co co co co co co co co co co co co co co C C CD C CD CD CD CD CD CD CD CD C C C C C C C H H H H H H~ H H H H H H H H H H H H H H co co co co co co co co co co co co co co co co co co co co co co co co co co CO CO CO CO CO CO C CO CO CO C co co co O HS H H H HS H H> H Q0 o Q0 o 1 w w o 1 o w N o o O oo Q0 o - I- o o o oooooo C 1 o Lo, o o o M, o F- Q0 Q0 O O O O OOOOO LO LO 11 O O1 Q O1 m m O1 m O OO O N m O1 O1 N O Lo Q0 Lc I- m m C- m Lc m m P- o P- I 1 11 oo ko C- VA VA VA VA VA VA VA VA VA CD CD CD CD CD CD CD CD - ) 00000000000002 00000 m o o o o o H H H H H H H H H H H H H H H H H H H H1 H H H H HH HH H H L H H H H H Z HZ 4 Z Z H4 Z 4 Z Z 4' Z 4HZ Z H 00000000000000000000I I I I 00000000000000000000 O M Q OS O OS OS OS OS r-I OS O OS OS OS O O O O O O O O N N N N N N N N NS N N N NS N N N N N N N CS C CS S CS CS S CS CS C CS S H CS C C128/151 C Amino acid sequences of light chain (LC) and heavy chain (HC) variable domain of pKal antibodies obtained from CDR1/2 and CDR3 spiking affinity maturation libraries based on X63-G06. 5 M203-AO1 LC QDIQMTQSPG TLSLSPGERA TLSCRTSQFV NSNYLAWYQQ TPGQAPRLLI YGASSRATGI 60 PDRFSGTGYG TDFTLTISRL EPEDYGTYYC QQSSRTPWTF GQGTRVEIK 109 M203-A01 HC 10 EVQLLESGGG LVQPGGSLRL SCAASGFTFS NYLMAWVRQA PGKGLEWVSW IVPSGGYTEY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARVA RGIAARSRTS YFDYWGQGTL 120 VTVSSASTKG PSVFPLAPSS KS 142 M203-A03 LC 15 QDIQMTQSPG TLSLSPGERA TLSCRTSQFV NSNYLAWYQQ TPGQAPRLLI YGASSRATGI 60 PDRFSGTGYG TDFTLTISRL EPEDYGTYYC QQSSRTPWTF GQGTRVEIK 109 M203-A03 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS VYMMIWVRQA PGKGLEWVSS ISPSGGQTTY 60 20 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARVA RGIAARSRTS YFDYWGQGTL 120 VTVSSASTKG PSVFPLAPSS KS 142 M204-A02 LC QDIQMTQSPG TLSLSPGERA TLSCRTSQFV NSNYLAWYQQ TPGQAPRLLI YGASSRATGI 60 25 PDRFSGTGYG TDFTLTISRL EPEDYGTYYC QQSSRTPWTF GQGTRVEIK 109 M204-A02 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS DYMMTWVRQA PGKGLqWVSY ISPSGGLTSY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARVA RGIAARSRTS YFDYWGQGTL 120 30 VTVSSASTKG PSVFPLAPSS KS 142 M204-E12 LC QDIQMTQSPG TLSLSPGERA TLSCRTSQFV NSNYLAWYQQ TPGQAPRLLI YGASSRATGI 60 PDRFSGTGYG TDFTLTISRL EPEDYGTYYC QQSSRTPWTF GQGTRVEIK 109 35 M204-E12 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS TYMMqWVRQA PGKGLEWVSY IGPSGGKTDY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARVA RGIAARSRTS YFDYWGQGTL 120 VTVSSASTKG PSVFPLAPSS KS 142 40 M205-A02 LC QDIQMTQSPG TLSLSPGERA TLSCRTSQFV NSNYLAWYQQ TPGQAPRLLI YGASSRATGI 60 PDRFSGTGYG TDFTLTISRL EPEDYGTYYC QQSSRTPWTF GQGTRVEIK 109 45 M205-A02 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS TYLMAWVRQA PGKGLEWVSG IVSSGGRTLY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARVA RGIAARSRTS YFDYWGQGTL 120 VTVSSASTKG PSVFPLAPSS KS 142 50 M205-A12 LC QDIQMTQSPG TLSLSPGERA TLSCRTSQFV NSNYLAWYQQ TPGQAPRLLI YGASSRATGI 60 PDRFSGTGYG TDFTLTISRL EPEDYGTYYC QQSSRTPWTF GQGTRVEIK 109 129/151 M205-A12 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS QYDMIWVRQA PGKGLEWVSY ISSSGGFTRY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARVA RGIAARSRTS YFDYWGQGTL 120 VTVSSASTKG PSVFPLAPSS KS 142 5 M205-B04 LC QDIQMTQSPG TLSLSPGERA TLSCRTSQFV NSNYLAWYQQ TPGQAPRLLI YGASSRATGI 60 PDRFSGTGYG TDFTLTISRL EPEDYGTYYC QQSSRTPWTF GQGTRVEIK 109 10 M205-B04 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS NYDMIWVRQA PGKGLEWVSS ISSSGGTTKY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARVA RGIAARSRTS YFDYWGQGTL 120 VTVSSASTKG PSVFPLAPSS KS 142 15 M205-Cll LC QDIQMTQSPG TLSLSPGERA TLSCRTSQFV NSNYLAWYQQ TPGQAPRLLI YGASSRATGI 60 PDRFSGTGYG TDFTLTISRL EPEDYGTYYC QQSSRTPWTF GQGTRVEIK 109 M205-Cll HC 20 EVQLLESGGG LVQPGGSLRL SCAASGFTFS QYMMMWVRQA PGKGLEWVSR ISPSGGSTLY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARVA RGIAARSRTS YFDYWGQGTL 120 VTVSSASTKG PSVFPLAPSS KS 142 M205-DO4 LC 25 QDIQMTQSPG TLSLSPGERA TLSCRTSQFV NSNYLAWYQQ TPGQAPRLLI YGASSRATGI 60 PDRFSGTGYG TDFTLTISRL EPEDYGTYYC QQSSRTPWTF GQGTRVEIK 109 M205-DO4 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS TYKMqWVRQA PGKGLEWVSS ISPSGGPTNY 60 30 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARVA RGIAARSRTS YFDYWGQGTL 120 VTVSSASTKG PSVFPLAPSS KS 142 M205-Ell LC QDIQMTQSPG TLSLSPGERA TLSCRTSQFV NSNYLAWYQQ TPGQAPRLLI YGASSRATGI 60 35 PDRFSGTGYG TDFTLTISRL EPEDYGTYYC QQSSRTPWTF GQGTRVEIK 109 M205-Ell HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS NYTMGWVRQA PGKGLEWVSS ISPSGGKTDY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARVA RGIAARSRTS YFDYWGQGTL 120 40 VTVSSASTKG PSVFPLAPSS KS 142 M205-F03 LC QDIQMTQSPG TLSLSPGERA TLSCRTSQFV NSNYLAWYQQ TPGQAPRLLI YGASSRATGI 60 PDRFSGTGYG TDFTLTISRL EPEDYGTYYC QQSSRTPWTF GQGTRVEIK 109 45 M205-F03 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS SqQMVWVRQA PGKGLEWVSY ISPSGGNTYY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARVA RGIAARSRTS YFDYWGQGTL 120 VTVSSASTKG PSVFPLAPSS KS 142 50 M205-HO1 LC QDIQMTQSPG TLSLSPGERA TLSCRTSQFV NSNYLAWYQQ TPGQAPRLLI YGASSRATGI 60 PDRFSGTGYG TDFTLTISRL EPEDYGTYYC QQSSRTPWTF GQGTRVEIK 109 55 M205-HO1 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS NYTMQWVRQA PGKGLqWVSY ISPSGGYTGY 60 130/151 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARVA RGIAARSRTS YFDYWGQGTL 120 VTVSSASTKG PSVFPLAPSS KS 142 M205-H08 LC 5 QDIQMTQSPG TLSLSPGERA TLSCRTSQFV NSNYLAWYQQ TPGQAPRLLI YGASSRATGI 60 PDRFSGTGYG TDFTLTISRL EPEDYGTYYC QQSSRTPWTF GQGTRVEIK 109 M205-H08 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS DYMMMWVRQA PGKGLEWVSS IVPSGGHTqY 60 10 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARVA RGIAARSRTS YFDYWGQGTL 120 VTVSSASTKG PSVFPLAPSS KS 142 M206-A06 LC QDIQMTQSPG TLSLSPGERA TLSCRTSQFV NSNYLAWYQQ TPGQAPRLLI YGASSRATGI 60 15 PDRFSGTGYG TDFTLTISRL EPEDYGTYYC QQSSRTPWTF GQGTRVEIK 109 M206-A06 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS NYMMGWVRQA PGKGLqWVSS ISPSGGLTKY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARVA RGIAARSRTS YFDYWGQGTL 120 20 VTVSSASTKG PSVFPLAPSS KS 142 M206-B10 LC QDIQMTQSPG TLSLSPGERA TLSCRTSQFV NSNYLAWYQQ TPGQAPRLLI YGASSRATGI 60 PDRFSGTGYG TDFTLTISRL EPEDYGTYYC QQSSRTPWTF GQGTRVEIK 109 25 M206-B10 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS qYLMAWVRQA PGKGLEWVSS IYPSGGWTKY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARVA RGIAARSRTS YFDYWGQGTL 120 VTVSSASTKG PSVFPLAPSS KS 142 30 M206-C03 LC QDIQMTQSPG TLSLSPGERA TLSCRTSQFV NSNYLAWYQQ TPGQAPRLLI YGASSRATGI 60 PDRFSGTGYG TDFTLTISRL EPEDYGTYYC QQSSRTPWTF GQGTRVEIK 109 35 M206-C03 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS qYMMVWVRQA PGKGLEWVSS IYSSGGNTPY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARVA RGIAARSRTS YFDYWGQGTL 120 VTVSSASTKG PSVFPLAPSS KS 142 40 M206-E02 LC QDIQMTQSPG TLSLSPGERA TLSCRTSQFV NSNYLAWYQQ TPGQAPRLLI YGASSRATGI 60 PDRFSGTGYG TDFTLTISRL EPEDYGTYYC QQSSRTPWTF GQGTRVEIK 109 M206-E02 HC 45 EVQLLESGGG LVQPGGSLRL SCAASGFTFS EYMMMWVRQA PGKGLEWVSV ISPSGGQTHY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARVA RGIAARSRTS YFDYWGQGTL 120 VTVSSASTKG PSVFPLAPSS KS 142 M206-FO1 LC 50 QDIQMTQSPG TLSLSPGERA TLSCRTSQFV NSNYLAWYQQ TPGQAPRLLI YGASSRATGI 60 PDRFSGTGYG TDFTLTISRL EPEDYGTYYC QQSSRTPWTF GQGTRVEIK 109 M206-FO1 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS GYMMVWVRQA PGKGLEWVSR ISPSGGPTIY 60 55 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARVA RGIAARSRTS YFDYWGQGTL 120 VTVSSASTKG PSVFPLAPSS KS 142 131/151 M206-F09 LC QDIQMTQSPG TLSLSPGERA TLSCRTSQFV NSNYLAWYQQ TPGQAPRLLI YGASSRATGI 60 PDRFSGTGYG TDFTLTISRL EPEDYGTYYC QQSSRTPWTF GQGTRVEIK 109 5 M206-F09 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS VYMMSWVRQA PGKGLEWVSS IVPSGGSTTY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARVA RGIAARSRTS YFDYWGQGTL 120 VTVSSASTKG PSVFPLAPSS KS 142 10 M206-H01 LC QDIQMTQSPG TLSLSPGERA TLSCRTSQFV NSNYLAWYQQ TPGQAPRLLI YGASSRATGI 60 PDRFSGTGYG TDFTLTISRL EPEDYGTYYC QQSSRTPWTF GQGTRVEIK 109 15 M206-H01 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS EYMMVWVRQA PGKGLEWVSR ISPSGGTTEY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARVA RGIAARSRTS YFDYWGQGTL 120 VTVSSASTKG PSVFPLAPSS KS 142 20 M206-H04 LC QDIQMTQSPG TLSLSPGERA TLSCRTSQFV NSNYLAWYQQ TPGQAPRLLI YGASSRATGI 60 PDRFSGTGYG TDFTLTISRL EPEDYGTYYC QQSSRTPWTF GQGTRVEIK 109 M206-H04 HC 25 EVQLLESGGG LVQPGGSLRL SCAASGFTFS SYMMVWVRQA PGKGLEWVSS ISPSGGYTIq 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARVA RGIAARSRTS YFDYWGQGTL 120 VTVSSASTKG PSVFPLAPSS KS 142 M206-H05 LC 30 QDIQMTQSPG TLSLSPGERA TLSCRTSQFV NSNYLAWYQQ TPGQAPRLLI YGASSRATGI 60 PDRFSGTGYG TDFTLTISRL EPEDYGTYYC QQSSRTPWTF GQGTRVEIK 109 M206-H05 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS GYKMqWVRQA PGKGLEWVSS ISPSGGITMY 60 35 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARVA RGIAARSRTS YFDYWGQGTL 120 VTVSSASTKG PSVFPLAPSS KS 142 M206-H08 LC QDIQMTQSPG TLSLSPGERA TLSCRTSQFV NSNYLAWYQQ TPGQAPRLLI YGASSRATGI 60 40 PDRFSGTGYG TDFTLTISRL EPEDYGTYYC QQSSRTPWTF GQGTRVEIK 109 M206-H08 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS DYMMAWVRQA PGKGLEWVSS IVPSGGHTHY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARVA RGIAARSRTS YFDYWGQGTL 120 45 VTVSSASTKG PSVFPLAPSS KS 142 M207-AO1 LC QDIQMTQSPG TLSLSPGERA TLSCRTSQFV NSNYLAWYQQ TPGQAPRLLI YGASSRATGI 60 PDRFSGTGYG TDFTLTISRL EPEDYGTYYC QQSSRTPWTF GQGTRVEIK 109 50 M207-AO1 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS HYLMTWVRQA PGKGLEWVSY ISPSGGHTIY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARVA RGISARSRTS CFDYWGQGTL 120 VTVSSASTKG PSVFPLAPSS KS 142 55 M207-A02 LC 132/151 QDIQMTQSPG TLSLSPGERA TLSCRTSQFV NSNYLAWYQQ TPGQAPRLLI YGASSRATGI 60 PDRFSGTGYG TDFTLTISRL EPEDYGTYYC QQSSRTPWTF GQGTRVEIK 109 M207-A02 HC 5 EVQLLESGGG LVQPGGSLRL SCAASGFTFS HYLMTWVRQA PGKGLEWVSY ISPSGGHTIY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TALYYCARVA RGIAARSRTI NLDYWGQGTL 120 VTVSSASTKG PSVFPLAPSS KS 142 M207-A04 LC 10 QDIQMTQSPG TLSLSPGERA TLSCRTSQFV NSNYLAWYQQ TPGQAPRLLI YGASSRATGI 60 PDRFSGTGYG TDFTLTISRL EPEDYGTYYC QQSSRTPWTF GQGTRVEIK 109 M207-A04 HC 15 EVQLLESGGG LVQPGGSLRL SCAASGFTFS HYLMTWVRQA PGKGLEWVSY ISPSGGHTIY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARVA RGIAARSRTR SFDYWGQGTL 120 VTVSSASTKG PSVFPLAPSS KS 142 M207-C05 LC 20 QDIQMTQSPG TLSLSPGERA TLSCRTSQFV NSNYLAWYQQ TPGQAPRLLI YGASSRATGI 60 PDRFSGTGYG TDFTLTISRL EPEDYGTYYC QQSSRTPWTF GQGTRVEIK 109 R0121-D02 = M0207-C05 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS HYLMTWVRQA PGKGLEWVSY ISPSGGHTIY 60 25 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARVG RGIAARSRTS YFDKWGQGTL 120 VTVSSASTKG PSVFPLAPSS KS 142 M208-A10 LC QDIQMTQSPG TLSLSPGERA TLSCRTSQFV NSNYLAWYQQ TPGQAPRLLI YGASSRATGI 60 30 PDRFSGTGYG TDFTLTISRL EPEDYGTYYC QQSSRTPWTF GQGTRVEIK 109 M208-A1O HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS HYLMTWVRQA PGKGLEWVSY ISPSGGHTIY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARVA RGIAARSRTS qFDHWGQGTL 120 35 VTVSSASTKG PSVFPLAPSS KS 142 M208-BO1 LC QDIQMTQSPG TLSLSPGERA TLSCRTSQFV NSNYLAWYQQ TPGQAPRLLI YGASSRATGI 60 PDRFSGTGYG TDFTLTISRL EPEDYGTYYC QQSSRTPWTF GQGTRVEIK 109 40 M208-BO1 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS HYLMTWVRQA PGKGLEWVSY ISPSGGHTIY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARVA RGIAARSRTS FFDqWGQGTL 120 VTVSSASTKG PSVFPLAPSS KS 142 45 M208-C06 LC QDIQMTQSPG TLSLSPGERA TLSCRTSQFV NSNYLAWYQQ TPGQAPRLLI YGASSRATGI 60 PDRFSGTGYG TDFTLTISRL EPEDYGTYYC QQSSRTPWTF GQGTRVEIK 109 50 M208-C06 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS HYLMTWVRQA PGKGLEWVSY ISPSGGHTIY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARVA RGIAARSRTS FIDYWGQGTL 120 VTVSSASTKG PSVFPLAPSS KS 142 55 M208-D12 LC QDIQMTQSPG TLSLSPGERA TLSCRTSQFV NSNYLAWYQQ TPGQAPRLLI YGASSRATGI 60 133/151 PDRFSGTGYG TDFTLTISRL EPEDYGTYYC QQSSRTPWTF GQGTRVEIK 109 M208-D12 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS HYLMTWVRQA PGKGLEWVSY ISPSGGHTIY 60 5 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARLA RGIAARSRTS YqDIWGQGTL 120 VTVSSASTKG PSVFPLAPSS KS 142 M208-E10 LC QDIQMTQSPG TLSLSPGERA TLSCRTSQFV NSNYLAWYQQ TPGQAPRLLI YGASSRATGI 60 10 PDRFSGTGYG TDFTLTISRL EPEDYGTYYC QQSSRTPWTF GQGTRVEIK 109 M208-E10 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS HYLMTWVRQA PGKGLEWVSY ISPSGGHTIY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARVA QGISARSRTS YFDYWGQGTL 120 15 VTVSSASTKG PSVFPLAPSS KS 142 M208-F04 LC QDIQMTQSPG TLSLSPGERA TLSCRTSQFV NSNYLAWYQQ TPGQAPRLLI YGASSRATGI 60 PDRFSGTGYG TDFTLTISRL EPEDYGTYYC QQSSRTPWTF GQGTRVEIK 109 20 M208-F04 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS HYLMTWVRQA PGKGLEWVSY ISPSGGHTIY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARVA RGIAARSRTS FFDYWGQGTL 120 VTVSSASTKG PSVFPLAPSS KS 142 25 M208-F10 LC QDIQMTQSPG TLSLSPGERA TLSCRTSQFV NSNYLAWYQQ TPGQAPRLLI YGASSRATGI 60 PDRFSGTGYG TDFTLTISRL EPEDYGTYYC QQSSRTPWTF GQGTRVEIK 109 30 M208-F10 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS HYLMTWVRQA PGKGLEWVSY ISPSGGHTIY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARVA RGIAARSRTS YFDqWGQGTL 120 VTVSSASTKG PSVFPLAPSS KS 142 35 M208-G02 LC QDIQMTQSPG TLSLSPGERA TLSCRTSQFV NSNYLAWYQQ TPGQAPRLLI YGASSRATGI 60 PDRFSGTGYG TDFTLTISRL EPEDYGTYYC QQSSRTPWTF GQGTRVEIK 109 40 M208-G02 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS HYLMTWVRQA PGKGLEWVSY ISPSGGHTIY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARVA RGIADRSRTS YSDYWGQGTL 120 VTVSSASTKG PSVFPLAPSS KS 142 45 M208-G03 LC QDIQMTQSPG TLSLSPGERA TLSCRTSQFV NSNYLAWYQQ TPGQAPRLLI YGASSRATGI 60 PDRFSGTGYG TDFTLTISRL EPEDYGTYYC QQSSRTPWTF GQGTRVEIK 109 M208-G03 HC 50 EVQLLESGGG LVQPGGSLRL SCAASGFTFS HYLMTWVRQA PGKGLEWVSY ISPSGGHTIY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARVA RGIAARSRTS YLDYWGQGTL 120 VTVSSASTKG PSVFPLAPSS KS 142 M208-H02 LC 55 QDIQMTQSPG TLSLSPGERA TLSCRTSQFV NSNYLAWYQQ TPGQAPRLLI YGASSRATGI 60 PDRFSGTGYG TDFTLTISRL EPEDYGTYYC QQSSRTPWTF GQGTRVEIK 109 134/151 M208-H02 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS HYLMTWVRQA PGKGLEWVSY ISPSGGHTIY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARVA RGIASRSRTR YCDYWGQGTL 120 5 VTVSSASTKG PSVFPLAPSS KS 142 M209-B01 LC QDIQMTQSPG TLSLSPGERA TLSCRTSQFV NSNYLAWYQQ TPGQAPRLLI YGASSRATGI 60 PDRFSGTGYG TDFTLTISRL EPEDYGTYYC QQSSRTPWTF GQGTRVEIK 109 10 M209-B01 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS HYLMTWVRQA PGKGLEWVSY ISPSGGHTIY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARVA RGIVARSRTS NFDqWGQGTL 120 15 VTVSSASTKG PSVFPLAPSS KS 142 M209-B09 LC QDIQMTQSPG TLSLSPGERA TLSCRTSQFV NSNYLAWYQQ TPGQAPRLLI YGASSRATGI 60 PDRFSGTGYG TDFTLTISRL EPEDYGTYYC QQSSRTPWTF GQGTRVEIK 109 20 M209-B09 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS HYLMTWVRQA PGKGLEWVSY ISPSGGHTIY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARVA QGIVARSRTS YLHqWGQGTL 120 VTVSSASTKG PSVFPLAPSS KS 142 25 M209-Bll LC QDIQMTQSPG TLSLSPGERA TLSCRTSQFV NSNYLAWYQQ TPGQAPRLLI YGASSRATGI 60 PDRFSGTGYG TDFTLTISRL EPEDYGTYYC QQSSRTPWTF GQGTRVEIK 109 30 M209-Bll HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS HYLMTWVRQA PGKGLEWVSY ISPSGGHTIY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARVA RGIAARSRTR YIDqWGQGTL 120 VTVSSASTKG PSVFPLAPSS KS 142 35 M209-C02 LC QDIQMTQSPG TLSLSPGERA TLSCRTSQFV NSNYLAWYQQ TPGQAPRLLI YGASSRATGI 60 PDRFSGTGYG TDFTLTISRL EPEDYGTYYC QQSSRTPWTF GQGTRVEIK 109 M209-C02 HC 40 EVQLLESGGG LVQPGGSLRL SCAASGFTFS HYLMTWVRQA PGKGLEWVSY ISPSGGHTIY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARVA RGIAYRRRTS YFDYWGQGTL 120 VTVSSASTKG PSVFPLAPSS KS 142 M209-Cll LC 45 QDIQMTQSPG TLSLSPGERA TLSCRTSQFV NSNYLAWYQQ TPGQAPRLLI YGASSRATGI 60 PDRFSGTGYG TDFTLTISRL EPEDYGTYYC QQSSRTPWTF GQGTRVEIK 109 M209-Cll HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS HYLMTWVRQA PGKGLEWVSY ISPSGGHTIY 60 50 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCAMVG QGIRGRSRTS YFAqWGQGTL 120 VTVSSASTKG PSVFPLAPSS KS 142 M209-C12 LC QDIQMTQSPG TLSLSPGERA TLSCRTSQFV NSNYLAWYQQ TPGQAPRLLI YGASSRATGI 60 55 PDRFSGTGYG TDFTLTISRL EPEDYGTYYC QQSSRTPWTF GQGTRVEIK 109 135/151 M209-C12 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS HYLMTWVRQA PGKGLEWVSY ISPSGGHTIY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARVG RGIAARSRTS qLDYWGQGTL 120 VTVSSASTKG PSVFPLAPSS KS 142 5 M0209-D02 LC QDIQMTQSPG TLSLSPGERA TLSCRTSQFV NSNYLAWYQQ TPGQAPRLLI YGASSRATGI 60 PDRFSGTGYG TDFTLTISRL EPEDYGTYYC QQSSRTPWTF GQGTRVEIK 109 10 M209-D02 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS HYLMTWVRQA PGKGLEWVSY ISPSGGHTIY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARVA RGITARSRTS YFDDWGQGTL 120 VTVSSASTKG PSVFPLAPSS KS 142 15 M209-DO3 LC QDIQMTQSPG TLSLSPGERA TLSCRTSQFV NSNYLAWYQQ TPGQAPRLLI YGASSRATGI 60 PDRFSGTGYG TDFTLTISRL EPEDYGTYYC QQSSRTPWTF GQGTRVEIK 109 M209-DO3 HC 20 EVQLLESGGG LVQPGGSLRL SCAASGFTFS HYLMTWVRQA PGKGLEWVSY ISPSGGHTIY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARVG RGIAARSRTS FFDqWGQGTL 120 VTVSSASTKG PSVFPLAPSS KS 142 M209-D12 LC 25 QDIQMTQSPG TLSLSPGERA TLSCRTSQFV NSNYLAWYQQ TPGQAPRLLI YGASSRATGI 60 PDRFSGTGYG TDFTLTISRL EPEDYGTYYC QQSSRTPWTF GQGTRVEIK 109 M209-D12 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS HYLMTWVRQA PGKGLEWVSY ISPSGGHTIY 60 30 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCATVA RGIAARSRTS YFDqWGQGTL 120 VTVSSASTKG PSVFPLAPSS KS 142 M209-E02 LC QDIQMTQSPG TLSLSPGERA TLSCRTSQFV NSNYLAWYQQ TPGQAPRLLI YGASSRATGI 60 35 PDRFSGTGYG TDFTLTISRL EPEDYGTYYC QQSSRTPWTF GQGTRVEIK 109 M209-E02 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS HYLMTWVRQA PGKGLEWVSY ISPSGGHTIY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARVA RGIAARSRTI LLDqWGQGTL 120 40 VTVSSASTKG PSVFPLAPSS KS 142 M209-E03 LC QDIQMTQSPG TLSLSPGERA TLSCRTSQFV NSNYLAWYQQ TPGQAPRLLI YGASSRATGI 60 PDRFSGTGYG TDFTLTISRL EPEDYGTYYC QQSSRTPWTF GQGTRVEIK 109 45 M209-E03 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS HYLMTWVRQA PGKGLEWVSY ISPSGGHTIY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARqA RGIAARSRTS YFDYWGQGTL 120 VTVSSASTKG PSVFPLAPSS KS 142 50 M209-F04 LC QDIQMTQSPG TLSLSPGERA TLSCRTSQFV NSNYLAWYQQ TPGQAPRLLI YGASSRATGI 60 PDRFSGTGYG TDFTLTISRL EPEDYGTYYC QQSSRTPWTF GQGTRVEIK 109 55 M209-F04 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS HYLMTWVRQA PGKGLEWVSY ISPSGGHTIY 60 136/151 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARVA RGIAARSRTS YLDqWSQGTL 120 VTVSSASTKG PSVFPLAPSS KS 142 M209-G01 LC 5 QDIQMTQSPG TLSLSPGERA TLSCRTSQFV NSNYLAWYQQ TPGQAPRLLI YGASSRATGI 60 PDRFSGTGYG TDFTLTISRL EPEDYGTYYC QQSSRTPWTF GQGTRVEIK 109 M209-G01 HC 10 EVQLLESGGG LVQPGGSLRL SCAASGFTFS HYLMTWVRQA PGKGLEWVSY ISPSGGHTIY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARVA qGISGRSRLS YVDYWGQGTL 120 VTVSSASTKG PSVFPLAPSS KS 142 M209-G07 LC 15 QDIQMTQSPG TLSLSPGERA TLSCRTSQFV NSNYLAWYQQ TPGQAPRLLI YGASSRATGI 60 PDRFSGTGYG TDFTLTISRL EPEDYGTYYC QQSSRTPWTF GQGTRVEIK 109 M209-G07 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS HYLMTWVRQA PGKGLEWVSY ISPSGGHTIY 60 20 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARVA RGIAARSRTS YFDTWGQGTL 120 VTVSSASTKG PSVFPLAPSS KS 142 M209-H03 LC QDIQMTQSPG TLSLSPGERA TLSCRTSQFV NSNYLAWYQQ TPGQAPRLLI YGASSRATGI 60 25 PDRFSGTGYG TDFTLTISRL EPEDYGTYYC QQSSRTPWTF GQGTRVEIK 109 M209-H03 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS HYLMTWVRQA PGKGLEWVSY ISPSGGHTIY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARVA QGIAARSRTT qFDYWGQGTL 120 30 VTVSSASTKG PSVFPLAPSS KS 142 M209-H07 LC QDIQMTQSPG TLSLSPGERA TLSCRTSQFV NSNYLAWYQQ TPGQAPRLLI YGASSRATGI 60 PDRFSGTGYG TDFTLTISRL EPEDYGTYYC QQSSRTPWTF GQGTRVEIK 109 35 M209-H07 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS HYLMTWVRQA PGKGLEWVSY ISPSGGHTIY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARVA RGIAARqRTS YYDYWGQGTL 120 VTVSSASTKG PSVFPLAPSS KS 142 40 M209-H09 LC QDIQMTQSPG TLSLSPGERA TLSCRTSQFV NSNYLAWYQQ TPGQAPRLLI YGASSRATGI 60 PDRFSGTGYG TDFTLTISRL EPEDYGTYYC QQSSRTPWTF GQGTRVEIK 109 45 M209-H09 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS HYLMTWVRQA PGKGLEWVSY ISPSGGHTIY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARVA RGIAARSRTV YFDHWGQGTL 120 VTVSSASTKG PSVFPLAPSS KS 142 50 M210-A06 LC QDIQMTQSPG TLSLSPGERA TLSCRTSQFV NSNYLAWYQQ TPGQAPRLLI YGASSRATGI 60 PDRFSGTGYG TDFTLTISRL EPEDYGTYYC QQSSRTPWTF GQGTRVEIK 109 M210-A06 HC 55 EVQLLESGGG LVQPGGSLRL SCAASGFTFS HYLMTWVRQA PGKGLEWVSY ISPSGGHTIY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARVA RGIAARSRTS qFDYWGQGTL 120 137/151 VTVSSASTKG PSVFPLAPSS KS 142 M210-B02 LC QDIQMTQSPG TLSLSPGERA TLSCRTSQFV NSNYLAWYQQ TPGQAPRLLI YGASSRATGI 60 5 PDRFSGTGYG TDFTLTISRL EPEDYGTYYC QQSSRTPWTF GQGTRVEIK 109 M210-B02 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS HYLMTWVRQA PGKGLEWVSY ISPSGGHTIY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCASVA RGIAARSRTS YFNqWGQGTL 120 10 VTVSSASTKG PSVFPLAPSS KS 142 M210-C12 LC QDIQMTQSPG TLSLSPGERA TLSCRTSQFV NSNYLAWYQQ TPGQAPRLLI YGASSRATGI 60 PDRFSGTGYG TDFTLTISRL EPEDYGTYYC QQSSRTPWTF GQGTRVEIK 109 15 M210-C12 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS HYLMTWVRQA PGKGLEWVSY ISPSGGHTIY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARVA QGIAARSRTS SVDqWGQGTL 120 VTVSSASTKG PSVFPLAPSS KS 142 20 M210-G04 LC QDIQMTQSPG TLSLSPGERA TLSCRTSQFV NSNYLAWYQQ TPGQAPRLLI YGASSRATGI 60 PDRFSGTGYG TDFTLTISRL EPEDYGTYYC QQSSRTPWTF GQGTRVEIK 109 25 M210-G04 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS HYLMTWVRQA PGKGLEWVSY ISPSGGHTIY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARVA TGIVARSRTR YFDqWGQGTL 120 VTVSSASTKG PSVFPLAPSS KS 142 30 M210-G10 LC QDIQMTQSPG TLSLSPGERA TLSCRTSQFV NSNYLAWYQQ TPGQAPRLLI YGASSRATGI 60 PDRFSGTGYG TDFTLTISRL EPEDYGTYYC QQSSRTPWTF GQGTRVEIK 109 M210-G1O HC 35 EVQLLESGGG LVQPGGSLRL SCAASGFTFS HYLMTWVRQA PGKGLEWVSY ISPSGGHTIY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARVA RGIAARSRTS YLDFWGQGTL 120 VTVSSASTKG PSVFPLAPSS KS 142 M210-HO1 LC 40 QDIQMTQSPG TLSLSPGERA TLSCRTSQFV NSNYLAWYQQ TPGQAPRLLI YGASSRATGI 60 PDRFSGTGYG TDFTLTISRL EPEDYGTYYC QQSSRTPWTF GQGTRVEIK 109 M210-HO1 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS HYLMTWVRQA PGKGLEWVSY ISPSGGHTIY 60 45 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARVA RGIAARSRNS qQDYWGQGTL 120 VTVSSASTKG PSVFPLAPSS KS 142 M210-H06 LC QDIQMTQSPG TLSLSPGERA TLSCRTSQFV NSNYLAWYQQ TPGQAPRLLI YGASSRATGI 60 50 PDRFSGTGYG TDFTLTISRL EPEDYGTYYC QQSSRTPWTF GQGTRVEIK 109 M210-H06 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS HYLMTWVRQA PGKGLEWVSY ISPSGGHTIY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARVA RGIAARSRTR YFDYWGQGTL 120 55 VTVSSASTKG PSVFPLAPSS KS 142 138/151 M210-H07 LC QDIQMTQSPG TLSLSPGERA TLSCRTSQFV NSNYLAWYQQ TPGQAPRLLI YGASSRATGI 60 PDRFSGTGYG TDFTLTISRL EPEDYGTYYC QQSSRTPWTF GQGTRVEIK 109 5 M210-H07 HC EVQLLESGGG LVQPGGSLRL SCAASGFTFS HYLMTWVRQA PGKGLEWVSY ISPSGGHTIY 60 ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCARVA RGIAARSRTR YFDqWGQGTL 120 VTVSSASTKG PSVFPLAPSS KS 142 10 EXAMPLE 8: Evaluation of Selected Antibody Inhibitors of Plasma Kallikrein Evaluation of selected optimized antibodies (X81-B01 and X67-D03) is shown in Table 14. Neither antibody has any putative deamidation, isomerization, or oxidation sites. 15 Table 14 Criteria X81-BO1 (IgG) X67-D03 (IgG) < nM Ki,app against human pKal 0.2 nM 0.1 nM < nM Ki,app against rodent pKal mouse - 11 pM mouse - 0.7 nM rat - 0.14 nM rat - 0.34 nM Does not bind prekallikrein no no Specific inhibitor with respect to fXIa, yes yes plasmin, and trypsin Inhibits bradykinin generation yes yes Inhibits pKal in presence of prekallikrein yes yes Competition for binding with aprotinin yes yes Stability in human serum nd nd* * not done; parental forms of both antibodies were shown to be stable in serum EXAMPLE 9: Epitope Mapping The region of pKal bound by selected anti-pKal antibodies was investigated using 20 several methods. First, competition assays were used to determine whether the antibodies competed for binding to pKal with known active site-directed inhibitors. Second, antibodies were grouped according to whether they were inhibitors or just binders to pKal. Third, epitopes were investigated using synthetic peptides and peptidic structures 139/151 based on the sequence and 3-dimensional structure of pKal. These peptidic structures are called "CLIPS" (Chemically Linked Peptides on Scaffolds) and the testing was performed by a fee for service company called Pepscan . Fourth, antibodies were tested for their ability to inhibit pKal from other species, 5 besides human, where the amino acid sequence of pKal has been determined in order to identify amino acids that may account for the differences in inhibition. Competition Assays Using a BIACORE@ SPR assay antibodies of interest were tested for competion 10 with a known active site inhibitor of pKal. EPI-KAL2 is potent (K app = 0.1 nM) active site inhibitor of pKal and a Kunitz domain inhibitor based on the first domain of tissue factor pathway inhibitor (Markland (1996) Iterative optimization of high-affinity protease inhibitors using phage display. 2. Plasma kallikrein and thrombin, Biochemistry 35(24):8058-67). Kunitz domains are known active site inhibitors of serine proteases, 15 such as pKal. The sequence of EPI-KAL2 is: EAMHSFCAFKADDGPCRAAHPRWFFNIFTRQCEEFSYGGCGGNQNRFESL EECKKMCTRD (amino acids in italics are those that differ from TFPI) 20 As shown in FIGURES 7A-7B, the antibodies X81-BO1 and X67-D03 were competed for binding to pKal in the presence or EPI-KAL2. This result indicates that these antibodies either bind in vicinity of the active site or allosteric changes in the conformation of the pKal-EPI-KAL2 complex prevent antibody binding. 25 Antibody Binders vs Inhibitors Antibodies that inhibit the activity of pKal either bind near the active site and preclude substrate interactions (competitive inhibitors) or that bind away from the active site and induce allosteric changes in the structure of the active site (noncompetitive 30 inhibitors). As shown in Table 15, for the listed antibodies, is a demonstration of whether they cross-react with mouse pKal as inhibitors and whether they bind prekallikrein. 140/151 Table 15. Binding Properties of Selected Anti-pKal Antibodies Number Antibody Binding Category human mouse CLIPS Ki,app Ki,app Peptide(s) (nM) (nM) Identified 2 M6-D09 2) inhibitor, prekallikrein 5.9 3.9 Cl, C5 binder, inhibits mouse and human pKal 5 M29-D09 3) inhibitor, does not bind 0.7 no C1, C4, prekallikrein, does not C7 inhibit mouse pKal 6 M35-G04 2) inhibitor, prekallikrein 2.9 8 Cl, C4 binder, inhibits mouse and human pKal 7 M145- 3) inhibitor, does not bind 0.79 800 Cl, C4 D1I prekallikrein, weak inhibitor of mouse pKal 8 M160- 4) inhibitor of both mouse 5 0.2 C2 G12 and human pKal, does not bind prekallikrein 9 X55-F01 4) inhibitor of both 0.4 2 C2, C3 mouse and human pKal, does not bind prekallikein 10 X73-H09 4) inhibitor, does not bind 20 70 C6 prekallikrein, weak inhibitor of human and mouse pKal 11 X81-B01 4) inhibitor of both mouse 0.1 0.011 C2, C3, and human pKal, does not C5, C6 bind prekallikein 12 A2 5) Negative control, does No binding No binding No not bind pKal, binds binding streptavidin C1-C7: peptides in pKal identified by CLIPS epitope mapping (see FIGURES 8 and 9A 9C). Cl corresponds to positions 55-67 of the catalytic domain, C2 to positions 81-94, 5 C3 to positions 101-108, C4 to positions 137-151, C5 to positions 162-178, C6 to positions 186-197, and C7 to positions 214-217. Epitope Mapping Using CLIPS The anti-pKal antibodies listed in Table 15, plus one negative control (A2) and 10 three antibodies that bound but did not inhibit pKal, were tested for binding to 5000 141/151 different synthetic CLIPS (Chemically Linked Peptides on Scaffolds) by Pepscan as described below in the CLIP METHODS sections. This analysis led to the identification of peptide regions in pKal that are likely to be a part of the antibody epitope for each of the tested antibodies (FIGURE 8). 5 CLIPS METHODS The linear and CLIPS peptides were synthesized based on the amino acid sequence of the target protein using standard Fmoc-chemistry and deprotected using trifluoric acid with scavengers. The constrained peptides were synthesized on chemical 10 scaffolds in order to reconstruct conformational epitopes, using Chemically Linked Peptides on Scaffolds (CLIPS) technology (Timmerman et al. (2007). For example, the single looped peptides were synthesized containing a dicysteine, which was cyclized by treating with alpha, alpha'-dibromoxylene and the size of the loop was varied by introducing cysteine residues at variable spacing. If other cysteines besides the newly 15 introduced cysteines were present, they were replaced by alanine. The side-chains of the multiple cysteines in the peptides were coupled to CLIPS templates by reacting onto credit-card format polypropylene PEPSCAN cards (455 peptide formats/card) with a 0.5 mM solution of CLIPS template such as 1,3-bis (bromomethyl) benzene in ammonium bicarbonate (20 mM, pH 7.9)/acetonitrile (1: 1(v/v)). The cards were gently shaken in the 20 solution for 30 to 60 minutes while completely covered in solution. Finally, the cards were washed extensively with excess of H 2 0 and sonicated in distrupt-buffer containing 1 percent SDS/0.1 percent beta-mercaptoethanol in PBS (pH 7.2) at 70'C for 30 minutes, followed by sonication in H 2 0 for another 45 minutes. The binding of antibody to each peptide were tested in a PEPSCAN-based ELISA. The 455-well credit card format 25 polypropylene cards containing the covalently linked peptides were incubated with primary antibody solution for example consisting of 1 micrograms/mL diluted in blocking solution called SQ (4% horse serum, 5% ovalbumin (w/v) in PBS/1% Tween or diluted in PBS eg, 20%SQ) overnight. After washing, the peptides were incubated with a 1/1000 dilution of rabbit anti-human antibody peroxidase or goat-anti-human FAB 30 peroxidase for one hour at 25' C. After washing, the peroxidase substrate 2,2'-azino-di 3-ethylbenzthiazoline sulfonate (ABTS) and 2 microlitres of 3 percent H 2 0 2 were added. 142/151 After one hour, the color development was measured. The color development was quantified with a charge coupled device (CCD) - camera and an image processing system (as firstly described in Slootstra et al., 1996). 5 Data calculation Raw Data: Optical density (Arbitrary OD units) The raw data are optical values obtained by a CCD-camera. The values mostly range from 0 to 3000, a log scale similar to 1 to 3 of a standard 96-well plate elisa-reader. First the CCD-camera makes a picture of the card before peroxidase coloring and then 10 again a picture after the peroxidase coloring. These two pictures are substracted from each other which results in the data which is called raw-data. This is copied into the Peplabm database. Then the values are copied to excel and this file is labeled as raw-data file. One follow-up manipulation is allowed. Sometimes a well contains an air-bubble resulting in a false-positive value, the cards are manually inspected and any values caused 15 by an air-bubble are scored as 0. Normally assays are not done in replicate (only upon request client request). Replicate tests are usually very similar. In addition, the dataset of thousands of peptides contains many peptides that are similar, thus results are never based on recognition of one peptide but on families of similar peptides. If one or a few peptides do not bind, or 20 exhibit lower binding, in a replicate experiment, a different epitope mapping is not normally attributed. Timmerman et al. (2007). Functional reconstruction and synthetic mimicry of a conformational epitope using CLIPSTM technology. J. Mol. Recognit. 20:283-99 25 Slootstra et al. (1996). Structural aspects of antibody-antigen interaction revealed through small random peptide libraries, Molecular Diversity,1, 87-96. EXAMPLE 10: Analysis of pKal Sequences from Different Species All available sequence of pKal were obtained from public databases and aligned 30 using ClustalW and regions were highlighted based on solvent accessibility, contact with an active site Kunitz inhibitor, and those peptides identified by CLIPS analysis 143/151 (FIGURES 9A-9C). Citrated plasma from each of these species was obtained and activated using a commercially available prekallikrein activator (from Enzyme Research Laboratories) according to the instructions of the manufacturer. Kallikrein activity was then measured in each of the samples in the presence or absence of X81-B01. 5 It was found that X81-B01 inhibited pKal from all the species except for pig pKal. Since the CLIPS analysis identified four peptides of pKal that X81-B01 binds to C2 (positions 81-94), C3 (positions 101-108), C5 (positions 162-178) and C6 (positions 186-197) - differences in the pig pKal sequence that correspond to these peptides were examined to identify potential amino acids changes that account for the lack of inhibition 10 of pig pKal by X81-B01. Peptides C2 and C3 are close in the sequence and are both highly similar in sequence among the different species. However, there is a difference at position 479. All the species except pig, frog, and dog have a serine at postion 479. The frog and dog pKal sequence has an alanine and a threonine at position 479, respectively; both of which are considered conservative substitutions for a serine. In contrast, the pig 15 pKal sequence has a leucine at position 479, which is a considerably less conservative substitution for a serine. Peptide C5 in pig pKal is highly similar to the sequences from the other species. However, at position 563, only in the pig pKal is a histidine present (bold in FIGURE 9C). This position in all the other species, except frog, is a tyrosine. In the frog pKal, which is inhibited by X81-B01, this position is a threonine. Peptide C6 in 20 pig pKal is again highly similar to the other sequences. However, only in the pig pKal sequence is position 585 a glutamate (in bold in FIGURE 9C). In all the other species this position is an aspartate. This analysis may indicate potentially critical residues in pKal that interact with X81-B01. 25 REFERENCES The contents of all cited references including literature references, issued patents, published or non-published patent applications cited throughout this application as well as those listed below are hereby expressly incorporated by reference in their entireties. In 30 case of conflict, the present application, including any definitions herein, will control. 144/151 1. Sonis ST, Tracey C, Shklar G, Jenson J, Florine D. 1990. An animal model for mucositis induced by cancer chemotherapy. Oral Surg Oral Med Oral Pathol. 69:437-43. 2. Sonis ST, Eilers JP, Epstein JB, LeVeque FG, Liggett WH Jr, Mulagha 5 MT, Peterson DE, Rose AH, Schubert MM, Spijkervet FK, Wittes JP. 1999. Validation of a new scoring system for the assessment of clinical trial research of oral mucositis induced by radiation or chemotherapy. Mucositis Study Group. Cancer. 85:2103-13. EQUIVALENTS 10 A number of embodiments of the invention have been described. Nevertheless, it will be understood that various modifications may be made without departing from the spirit and scope of the invention. Accordingly, other embodiments are within the scope of the following claims. 145/151

Claims (27)

1. A method for treating or preventing mucositis, the method comprising administering an effective amount of an isolated inhibitor of kallikrein to a subject having mucositis or who is at risk for developing mucositis.

2. The method of claim 1, wherein the inhibitor of kallikrein is an inhibitor of plasma kallikrein.

3. The method of claim 2, wherein the inhibitor of plasma kallikrein comprises a polypeptide that comprises the amino acid sequence: Xaal Xaa2 Xaa3 Xaa4 Cys Xaa6 Xaa7 Xaa8 Xaa9 Xaal0 Xaall Gly Xaa13 Cys Xaal5 Xaa16 Xaa17 Xaal8 Xaa19 Xaa2O Xaa2l Xaa22 Xaa23 Xaa24 Xaa25 Xaa26 Xaa27 Xaa28 Xaa29 Cys Xaa31 Xaa32 Phe Xaa34 Xaa35 Gly Gly Cys Xaa39 Xaa4O Xaa4l Xaa42 Xaa43 Xaa44 Xaa45 Xaa46 Xaa47 Xaa48 Xaa49 Xaa5O Cys Xaa52 Xaa53 Xaa54 Cys Xaa56 Xaa57 Xaa58 (SEQ ID NO:1), wherein Xaal, Xaa2, Xaa3, Xaa4, Xaa56, Xaa57 or Xaa58 are each individually any amino acid or absent; Xaal0 is an amino acid selected from the group consisting of: Asp and Glu; Xaal 1 is an amino acid selected from the group consisting of: Asp, Gly, Ser, Val, Asn, Ile, Ala and Thr; Xaa13 is an amino acid selected from the group consisting of: Arg, His, Pro, Asn, Ser, Thr, Ala, Gly, Lys and Gln; Xaa15 is an amino acid selected from the group consisting of: Arg, Lys, Ala, Ser, Gly, Met, Asn and Gin; Xaa16 is an amino acid selected from the group consisting of: Ala, Gly, Ser, Asp and Asn; Xaa17 is an amino acid selected from the group consisting of: Ala, Asn, Ser, Ile, Gly, Val, Gln and Thr; Xaal8 is an amino acid selected from the group consisting of: His, Leu, Gln and Ala; 146/151 Xaa19 is an amino acid selected from the group consisting of: Pro, Gln, Leu, Asn and Ile; Xaa2l is an amino acid selected from the group consisting of: Trp, Phe, Tyr, His and Ile; Xaa22 is an amino acid selected from the group consisting of: Tyr and Phe; Xaa23 is an amino acid selected from the group consisting of: Tyr and Phe; Xaa31 is an amino acid selected from the group consisting of: Glu, Asp, Gln, Asn, Ser, Ala, Val, Leu, Ile and Thr; Xaa32 is an amino acid selected from the group consisting of: Glu, Gin, Asp Asn, Pro, Thr, Leu, Ser, Ala, Gly and Val; Xaa34 is an amino acid selected from the group consisting of: Thr, Ile, Ser, Val, Ala, Asn, Gly and Leu; Xaa35 is an amino acid selected from the group consisting of: Tyr, Trp and Phe; Xaa39 is an amino acid selected from the group consisting of: Glu, Gly, Ala, Ser and Asp; Xaa4O is an amino acid selected from the group consisting of: Gly and Ala; Xaa43 is an amino acid selected from the group consisting of: Asn and Gly; Xaa45 is an amino acid selected from the group consisting of: Phe and Tyr; and wherein the polypeptide inhibits kallikrein.

4. The method of claim 3, wherein Xaa10 is Asp.

5. The method of claim 3, wherein Xaal 1 is Asp.

6. The method of claim 3, wherein Xaa13 is Pro, Xaa15 is Arg, Xaal6 is Ala, Xaa17 is Ala, Xaal8 is His and Xaal9 is Pro.

7. The method of claim 3, wherein Xaa2l is Trp.

8. The method of claim 3, wherein Xaa31 is Glu. 147/151

9. The method of claim 3, wherein Xaa32 is Glu.

10. The method of claim 3, wherein Xaa34 is Ile.

11. The method of claim 3, wherein Xaa35 is Tyr.

12. The method of claim 3, wherein Xaa39 is Glu.

13. The method of claim 3, wherein the polypeptide comprises: Met His Ser Phe Cys Ala Phe Lys Ala Asp Asp Gly Pro Cys Arg Ala Ala His Pro Arg Trp Phe Phe Asn Ile Phe Thr Arg Gin Cys Glu Glu Phe Ile Tyr Gly Gly Cys Glu Gly Asn Gin Asn Arg Phe Glu Ser Leu Glu Glu Cys Lys Lys Met Cys Thr Arg Asp (amino acids 3-60 of SEQ ID NO:2).

14. The method of claim 13, wherein the polypeptide further comprises a Glu-Ala sequence prior to the amino terminal Met residue.

15. The method of claim 3, wherein the polypeptide consists of: Met His Ser Phe Cys Ala Phe Lys Ala Asp Asp Gly Pro Cys Arg Ala Ala His Pro Arg Trp Phe Phe Asn Ile Phe Thr Arg Gln Cys Glu Glu Phe Ile Tyr Gly Gly Cys Glu Gly Asn Gln Asn Arg Phe Glu Ser Leu Glu Glu Cys Lys Lys Met Cys Thr Arg Asp (amino acids 3-60 of SEQ ID NO:2).

16. The method of claim 3, wherein the polypeptide comprises: Glu Ala Met His Ser Phe Cys Ala Phe Lys Ala Asp Asp Gly Pro Cys Arg Ala Ala His Pro Arg Trp Phe Phe Asn Ile Phe Thr Arg Gln Cys Glu Glu Phe Ile Tyr Gly Gly Cys Glu Gly Asn Gln Asn Arg Phe Glu Ser Leu Glu Glu Cys Lys Lys Met Cys Thr Arg Asp (SEQ ID NO:2).

17. The method of claim 3, wherein the polypeptide consists of: Glu Ala Met His Ser Phe Cys Ala Phe Lys Ala Asp Asp Gly Pro Cys Arg Ala Ala His Pro Arg Trp Phe Phe 148/151 Asn Ile Phe Thr Arg Gin Cys Glu Glu Phe Ile Tyr Gly Gly Cys Glu Gly Asn Gin Asn Arg Phe Glu Ser Leu Glu Glu Cys Lys Lys Met Cys Thr Arg Asp (SEQ ID NO:2).

18. The method of claim 2, wherein the inhibitor of plasma kallikrein comprises a plasma kallikrein binding protein comprising a heavy chain immunoglobulin variable domain sequence and a light chain immunoglobulin variable domain sequence, wherein: the heavy chain immunoglobulin variable domain sequence comprises one, two, or three CDR regions from the heavy chain variable domain of a protein described herein, and the light chain immunoglobulin variable domain sequence comprises one, two, or three CDR regions from the light chain variable domain of a protein described herein, wherein the protein binds to plasma kallikrein.

19. The method of claim 18, wherein the heavy chain immunoglobulin variable domain sequence comprises one, two, or three CDR regions from the heavy chain variable domain of M162-A04, M160-G12, M142-H08, X63-G06, X81-B01, X67-D03, or X67-G04, and the light chain immunoglobulin variable domain sequence comprises one, two, or three CDR regions from the light chain variable domain of M162-A04, M160-G12, M142 H08, X63-G06, X81-B01, X67-D03, or X67-G04 (respectively).

20. The method of claim 18, wherein, the one, two, or three CDR regions from the heavy chain variable domain are from X81-BO1 and the one, two, or three CDR regions from the light chain variable domain are from X81-BO 1.

21. The method of claim 18, wherein, the one, two, or three CDR regions from the heavy chain variable domain are from X67-D03 and the one, two, or three CDR regions from the light chain variable domain are from X67-D03. 149/151

22. The method of claim 1, wherein the mucositis is selected from the group consisting of oral, esophageal, pharyngeal and gastrointestinal mucositis.

23. The method of claim 22, wherein the mucositis is oral mucositis.

24. The method of claim 1, further comprising administering palifermin.

25. A composition comprising a therapeutically effective amount of the isolated kallikrein inhibitor of claim 1 and a therapeutically effective amount of palifermin.

26. A kit, wherein the kit comprises: a container comprising a isolated kallikrein inhibitor; and instructions for use of said kallikrein inhibitor for the treatment of mucositis.

27. The kit of claim 26, further comprising a container comprising palifermin. Dyax Corp. Patent Attorneys for the Applicantl Nominated Person SPRUSON & FERGUSON 150/151