Classifications

• • C—CHEMISTRY; METALLURGY
  • C07—ORGANIC CHEMISTRY
  • C07K—PEPTIDES
  • C07K16/00—Immunoglobulins [IGs], e.g. monoclonal or polyclonal antibodies
  • C07K16/18—Immunoglobulins [IGs], e.g. monoclonal or polyclonal antibodies against material from animals or humans
  • C07K16/28—Immunoglobulins [IGs], e.g. monoclonal or polyclonal antibodies against material from animals or humans against receptors, cell surface antigens or cell surface determinants
  • C07K16/2803—Immunoglobulins [IGs], e.g. monoclonal or polyclonal antibodies against material from animals or humans against receptors, cell surface antigens or cell surface determinants against the immunoglobulin superfamily
  • C07K16/2818—Immunoglobulins [IGs], e.g. monoclonal or polyclonal antibodies against material from animals or humans against receptors, cell surface antigens or cell surface determinants against the immunoglobulin superfamily against CD28 or CD152
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61P—SPECIFIC THERAPEUTIC ACTIVITY OF CHEMICAL COMPOUNDS OR MEDICINAL PREPARATIONS
  • A61P29/00—Non-central analgesic, antipyretic or antiinflammatory agents, e.g. antirheumatic agents; Non-steroidal antiinflammatory drugs [NSAID]
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61P—SPECIFIC THERAPEUTIC ACTIVITY OF CHEMICAL COMPOUNDS OR MEDICINAL PREPARATIONS
  • A61P37/00—Drugs for immunological or allergic disorders
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61P—SPECIFIC THERAPEUTIC ACTIVITY OF CHEMICAL COMPOUNDS OR MEDICINAL PREPARATIONS
  • A61P37/00—Drugs for immunological or allergic disorders
  • A61P37/02—Immunomodulators
  • A61P37/06—Immunosuppressants, e.g. drugs for graft rejection
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61P—SPECIFIC THERAPEUTIC ACTIVITY OF CHEMICAL COMPOUNDS OR MEDICINAL PREPARATIONS
  • A61P37/00—Drugs for immunological or allergic disorders
  • A61P37/08—Antiallergic agents
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61K—PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
  • A61K39/00—Medicinal preparations containing antigens or antibodies
  • A61K2039/505—Medicinal preparations containing antigens or antibodies comprising antibodies
• • C—CHEMISTRY; METALLURGY
  • C07—ORGANIC CHEMISTRY
  • C07K—PEPTIDES
  • C07K2317/00—Immunoglobulins specific features
  • C07K2317/10—Immunoglobulins specific features characterized by their source of isolation or production
  • C07K2317/14—Specific host cells or culture conditions, e.g. components, pH or temperature
• • C—CHEMISTRY; METALLURGY
  • C07—ORGANIC CHEMISTRY
  • C07K—PEPTIDES
  • C07K2317/00—Immunoglobulins specific features
  • C07K2317/30—Immunoglobulins specific features characterized by aspects of specificity or valency
  • C07K2317/35—Valency
• • C—CHEMISTRY; METALLURGY
  • C07—ORGANIC CHEMISTRY
  • C07K—PEPTIDES
  • C07K2317/00—Immunoglobulins specific features
  • C07K2317/50—Immunoglobulins specific features characterized by immunoglobulin fragments
  • C07K2317/52—Constant or Fc region; Isotype
• • C—CHEMISTRY; METALLURGY
  • C07—ORGANIC CHEMISTRY
  • C07K—PEPTIDES
  • C07K2317/00—Immunoglobulins specific features
  • C07K2317/50—Immunoglobulins specific features characterized by immunoglobulin fragments
  • C07K2317/52—Constant or Fc region; Isotype
  • C07K2317/524—CH2 domain
• • C—CHEMISTRY; METALLURGY
  • C07—ORGANIC CHEMISTRY
  • C07K—PEPTIDES
  • C07K2317/00—Immunoglobulins specific features
  • C07K2317/50—Immunoglobulins specific features characterized by immunoglobulin fragments
  • C07K2317/52—Constant or Fc region; Isotype
  • C07K2317/526—CH3 domain
• • C—CHEMISTRY; METALLURGY
  • C07—ORGANIC CHEMISTRY
  • C07K—PEPTIDES
  • C07K2317/00—Immunoglobulins specific features
  • C07K2317/50—Immunoglobulins specific features characterized by immunoglobulin fragments
  • C07K2317/56—Immunoglobulins specific features characterized by immunoglobulin fragments variable (Fv) region, i.e. VH and/or VL
• • C—CHEMISTRY; METALLURGY
  • C07—ORGANIC CHEMISTRY
  • C07K—PEPTIDES
  • C07K2317/00—Immunoglobulins specific features
  • C07K2317/50—Immunoglobulins specific features characterized by immunoglobulin fragments
  • C07K2317/56—Immunoglobulins specific features characterized by immunoglobulin fragments variable (Fv) region, i.e. VH and/or VL
  • C07K2317/565—Complementarity determining region [CDR]
• • C—CHEMISTRY; METALLURGY
  • C07—ORGANIC CHEMISTRY
  • C07K—PEPTIDES
  • C07K2317/00—Immunoglobulins specific features
  • C07K2317/70—Immunoglobulins specific features characterized by effect upon binding to a cell or to an antigen
  • C07K2317/74—Inducing cell proliferation
• • C—CHEMISTRY; METALLURGY
  • C07—ORGANIC CHEMISTRY
  • C07K—PEPTIDES
  • C07K2317/00—Immunoglobulins specific features
  • C07K2317/90—Immunoglobulins specific features characterized by (pharmaco)kinetic aspects or by stability of the immunoglobulin
  • C07K2317/94—Stability, e.g. half-life, pH, temperature or enzyme-resistance
• • C—CHEMISTRY; METALLURGY
  • C07—ORGANIC CHEMISTRY
  • C07K—PEPTIDES
  • C07K2318/00—Antibody mimetics or scaffolds
  • C07K2318/10—Immunoglobulin or domain(s) thereof as scaffolds for inserted non-Ig peptide sequences, e.g. for vaccination purposes
• • C—CHEMISTRY; METALLURGY
  • C07—ORGANIC CHEMISTRY
  • C07K—PEPTIDES
  • C07K2319/00—Fusion polypeptide
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
  • Y02A—TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE
  • Y02A50/00—TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE in human health protection, e.g. against extreme weather
  • Y02A50/30—Against vector-borne diseases, e.g. mosquito-borne, fly-borne, tick-borne or waterborne diseases whose impact is exacerbated by climate change

Definitions

• the invention relates to recombinant monovalent antibodies, in particular IgG antibodies, and to their therapeutic uses.
• An antibody (immunoglobulin) molecule is a Y-shaped tetrameric protein composed of two heavy (H) and two light (L) polypeptide chains held together by covalent disulfide bonds and noncovalent interactions.
• Each light chain is composed of one variable domain (VL) and one constant domain (CL).
• Each heavy chain has one variable domain (VH) and a constant region, which in the case of IgG, IgA, and IgD, comprises three domains termed CHl, CH2, and CH3 (IgM and IgE have a fourth domain, CH4).
• VH variable domain
• CH2 constant domain
• IgM and IgE have a fourth domain, CH4 domain
• CH4 fourth domain
• the CHl and CH2 domains are separated by a flexible hinge region, which is a proline and cysteine rich segment of variable length (generally from about 10 to about 60 amino acids in IgG).
• variable domains show considerable variation in amino acid composition from one antibody to another.
• Each of the VH and the VL variable domains comprises three regions of extreme variability, which are termed the complementarity- determining regions (CDRs), separated by less variable regions called the framework regions (FRs).
• CDRs complementarity- determining regions
• FRs framework regions
• the non-covalent association between the VH and the VL region forms the Fv fragment (for "fragment variable”) which contains one of the two antigen-binding sites of the antibody.
• ScFv fragments for single chain fragment variable
• can be obtained by genetic engineering associates in a single polypeptide chain the VH and the VL region of an antibody, separated by a peptide linker.
• Other functional immunoglobulin fragments can be obtained by proteolytic fragmentation of the immunoglobulin molecule.
• Papain treatment splits the molecule into three fragments : two heterodimeric Fab fragments (for 'fragment antigen binding'), each associating the VL and CL domains of the light chain with the VH and CHl domains of the heavy chain, and one homodimeric Fc fragment (for "fragment crystalline"), which comprises the CH2 and CH3 (and eventually CH4) domains of the light chain.
• Pepsin treatment produces the F(ab)'2 fragment which associates two Fab fragments, and several small fragments.
• the Fc fragment does not bind the antigen, but is responsible for the effector functions of the antibody, including in particular binding to Fc receptors and complement fixation.
• the Fv, Fab, and F(ab)'2 fragments retain the antigen-binding ability of the whole antibody.
• the F(ab)'2 fragments like the whole immunoglobumin molecule, are divalent (i.e. they contain two antigen binding sites and can bind and precipitate the antigen), while the Fv and Fab fragments are monovalent (they contain one antigen binding site, and can bind but cannot precipitate the antigen).
• Antibodies directed against cell-surface receptors are of great interest for the development of therapeutic agents for various disorders and diseases.
• antibodies having antagonistic properties when used as monovalent fragments may also show agonistic effects when used as full length antibodies.
• These agonistic effects result from the bivalency of the full-length antibodies, which induces the crosslinking of the target receptors on the cell surface, leading to receptor activation. This phenomenon is unwanted when the desired therapeutic activity relies upon an antagonistic effect.
• receptors that are activated by crosslinking include CD28, CD3 (DAMLE et al., J. Immunol., 140, 1753-61, 1988; ROUTLEDGE et al., Eur J Immunol, 21, 2717-25, 1991), TNF receptors, etc....
• the monovalent forms of antagonistic antibodies are devoid of agonistic activity. Therefore, they are useful therapeutic agents to block a cell receptor without inducing its cross-linking.
• their therapeutic use is hampered by their short half-life in vivo; they are eliminated within minutes and would require a continuous administration.
• it has been proposed to fuse these monovalent fragments with large molecules such as water-soluble proteins (PCT WO02051871) or polyethylene glycol (BLICK & CURRAN, BioDrugs, 21, 195-201; discussion 02-3, 2007).
• Another approach for producing monovalent antibodies has been to construct fusion proteins associating one Fab fragment (i.e an heterodimer comprising the VL and the CL regions of the light chain, and the VH and the CHl region of the heavy chain) with one Fc fragment (i.e an homodimer comprising the CH2 and CH3 regions of the heavy chains).
• Fab fragment i.e an heterodimer comprising the VL and the CL regions of the light chain, and the VH and the CHl region of the heavy chain
• Fc fragment i.e an homodimer comprising the CH2 and CH3 regions of the heavy chains
• PCT WO 2007/048037 describes monovalent antibodies which are heterodimers resulting from the association of an immunoglobulin heavy chain with a fusion protein comprising an immunoglobulin light chain and a Fc molecule.
• An advantage of this approach is that the resulting antibodies contain an IgG Fc domain, which in some cases, is useful if one desires to retain some of the effector functions of the IgG molecule, and which also allows to target the molecule to the neonatal Fc receptor (FcRn) expressed by endothelial cells.
• This receptor actively traps several macromolecules, including antibodies, inside the blood stream conferring them an extended serum half-live. The binding of IgG molecules to this receptor facilitates their transport, and allows their protection from degradation.
• the IgG Fc domain of immunoglobulins has also been utilized to form fusion proteins with molecules other than antibodies, for instance cytokines, growth factors, soluble growth factors, allowing to extend their half-life in the bloodstream, and also to deliver them by non-invasive routes, for instance by pulmonary administration (DUMONT et al., BioDrugs, 20, 151-60, 2006).
• the fusion proteins containing the IgG In the case of monovalent antibodies, the fusion proteins containing the IgG
• Fc domain which have been described until now also comprise the CL and/or the CHl region. It is generally believed that these regions, which are part of the Fab fragment, play an important part in the correct assembly of the IgG molecule, and can also influence the antigen/antibody interaction.
• CD28 receptor one of the cell surface receptors known to be stimulated after its engagement by bivalent antibodies, and which can be efficiently blocked by certain monovalent fragments of some antibodies, is the CD28 receptor.
• Fab fragments or with a fusion protein comprising a scFv fragment of the anti-CD28 monoclonal antibody CD28.3, fused with alpha 1 -antitrypsin VANHOVE et al., Blood, 102, 564-70, 2003.
• This approach demonstrated an efficacy in vitro as well as in organ transplantation in mice and in primates (POIRIER et al., World Transplant Congress, Sydney, Australia. August 16-21, 2008).
• the inventors have sought to further improve the pharmacokinetics properties of monovalent fragments of CD28.3. With this purpose, they have first attempted to construct a recombinant monovalent antibody similar to those disclosed in the prior art, by fusing the each of the VH and VL domains of CD28.3 to the CH1-CH2-CH3 domains of an heterologous IgG molecule. However this attempt failed to result in a protein with the required antibody activity.
• the inventors then tried to remove the CHl domains of these fusion proteins and found that the resulting monovalent antibody was secreted and active, and that it behaves in vitro like its corresponding Fab fragment. Further, after intravenous injection in mice, it showed an elimination half-live that was significantly longer than Fab fragments and not significantly different from IgG antibodies.
• an object of the present invention is a recombinant monovalent antibody derived from a parent antibody directed against an antigen of interest, wherein said recombinant antibody is an heterodimer of:
• - a first protein chain consisting essentially of, from its N-terminus to its C-terminus: * a region A having the structure of the VH domain of an immunoglobulin, said region A comprising the CDRs of the heavy chain of said parent antibody;
• the parent antibody can be any antibody directed against the antigen of interest; it can be a native monoclonal antibody; it can also be a recombinant or synthetic antibody, such as a chimeric antibody, a humanized antibody, or an antibody originating from phage-display or ribosome display technologies.
• a region having the structure of the VH or of the VL domain of an immunoglobulin comprises, as indicated above, four framework regions (FRs), connected by three hypervariable regions or complementarity determining regions (CDRs) which are involved in antigen recognition specificity.
• regions A and A' can consist of the native VH or VL domains of the parent antibody; however, they can also be obtained by incorporating the CDRs of the parent antibody into the framework regions (FRs) of another antibody, in particular of an antibody of human origin, using techniques, known in themselves, of CDR grafting.
• the peptide linker of region B may comprises from 0 to 16 amino acids. It comprises preferably 5 to 7 amino acids.
• suitable peptide linkers are those which are used in the construction of scFv fragments, such are those disclosed for instance by FREUND et al. (FEBS Lett. 320, 97-100, 1993) or by SHAN et al. (J Immunol. 162, 6589-95, 1999).
• Said peptide linker may be devoid of cysteine residues, or may comprise one or more cysteine residue(s).
• a peptide linker devoid of cysteine residues will be preferred if the monovalent antibody is to be produced in the E. coli periplasm.
• An example of a peptide linker devoid of cysteine residues is a peptide having the sequence TVAAPS (SEQ ID NO: 5).
• a peptide linker comprising cysteine residues allows the formation of inter-chain disulfide bonds, which help to stabilize the heterodimer.
• a peptide linker comprising cysteine residues one can use for instance the hinge region of a naturally occurring IgG.
• a preferred hinge region is the hinge region of IgG2 immunoglobulins having the sequence ERKCCVECPPCP (SEQ ID NO: 12), which provides a high stability.
• the CH2 and CH3 domains are preferably those of an immunoglobulin of human origin of the IgG isotype.
• Said IgG can belong to any of the IgG subclasses (IgGl, IgG2, IgG3 or IgG4). Preferably, it belongs to the IgGl subclass or the IgG4 subclass.
• the first and/or the second protein chain can further comprise one or more optional polypeptide sequence(s) which is (are) not involved in the biological properties of the recombinant monovalent antibody, but may facilitate its detection or purification.
• said polypeptide sequence can be a tag polypeptide, such as a streptavidin-binding peptide, an hexa-histidine (His 6 ) tag, or a FLAG-tag.
• the first and/or the second protein chain can be glycosylated or not.
• the parent antibody is the monoclonal antibody CD28.3, produced by the hybridoma CNCM 1-2582.
• the hybridoma CNCM 1-2582 is disclosed in PCT WO02051871, and has been deposited, according to the terms of the Treaty of Budapest, on Nov. 28, 2000, with the CNCM (Collection Nationale de Cultures de Microorganismes, 25 rue du Dondel Roux, 75724 PARIS CEDEX 15).
• a particular example of a recombinant monovalent antibody of the invention which is described in detail in the Examples below, is an antibody wherein the polypeptide sequence of the first protein chain is SEQ ID NO: 2, and the polypeptide sequence of the second protein chain is SEQ ID NO: 4.
• Another example of a recombinant monovalent antibody of the invention is an antibody wherein the polypeptide sequence of the first protein chain is SEQ ID NO: 13, and the polypeptide sequence of the second protein chain is SEQ ID NO: 14.
• Another object of the invention is a polynucleotide comprising a sequence encoding the first protein chain and/or a sequence encoding the second protein chain of a recombinant monovalent antibody of the invention.
• Said polynucleotides may also comprise additional sequences: for instance they may advantageously comprise a sequence encoding a leader sequence or signal peptide allowing secretion of said protein chain. They may optionally also comprise one or more sequence(s) encoding one or more tag polypeptide(s).
• the present invention also encompasses recombinant vectors, in particular expression vectors, comprising a polynucleotide of the invention, associated with transcription- and translation-controlling elements which are active in the host cell chosen.
• Vectors which can be used to construct expression vectors in accordance with the invention are known in themselves, and will be chosen in particular as a function of the host cell intended to be used.
• the present invention also encompasses host-cells transformed with a polynucleotide of the invention.
• said host cell is transformed with a polynucleotide comprising a sequence encoding the first protein chain of a recombinant monovalent antibody of the invention and a polynucleotide comprising a sequence encoding the second protein chain of a recombinant monovalent antibody of the invention, and expresses said recombinant antibody.
• Said polynucleotides can be inserted in the same expression vector, or in two separate expression vectors.
• Host cells which can be used in the context of the present invention can be prokaryotic or eukaryotic cells.
• eukaryotic cells which can be used, mention will in particular be made of plant cells, cells from yeast, such as Saccharomyces, insect cells, such as Drosophila or Spodoptera cells, and mammalian cells such as HeLa, CHO, 3T3, C 127, BHK, COS, etc., cells.
• Still another object of the invention is a method for preparing a recombinant monovalent antibody of the invention, Said method comprises culturing an host-cell transformed with a polynucleotide comprising a sequence encoding the first protein chain of a recombinant monovalent antibody of the invention, and with a polynucleotide comprising a sequence encoding the second protein chain of a recombinant monovalent antibody of the invention, and recovering said recombinant monovalent antibody from said culture.
• the protein If the protein is secreted by the host-cell, it can be recovered directly from the culture medium; if not, cell lysis will be carried out beforehand.
• the protein can then be purified from the culture medium or from the cell lysate, by conventional procedures, known in themselves to those skilled in the art, for example by fractionated precipitation, in particular precipitation with ammonium sulfate, electrophoresis, gel filtration, affinity chromatography, etc.
• a subject of the invention is also a method for producing a protein in accordance with the invention, characterized in that it comprises culturing at least one cell in accordance with the invention, and recovering said protein from said culture.
• the recombinant monovalent antibodies of the invention can be used to obtain medicinal products. These medicinal products are also part of the object of the invention.
• recombinant monovalent antibodies of the invention derived from the parent antibody CD28.3 can be used to obtain immunosuppressant medicinal products which selectively blocks T cell activation phenomena involving the CD28 receptor.
• Such immunosuppressant medicinal products which act by selective blocking of CD28 have applications in all T lymphocyte-dependent pathological conditions, including in particular transplant rejection, graft-versus-host disease, T lymphocyte-mediated autoimmune diseases, such as type I diabetes, rheumatoid arthritis or multiple sclerosis, and type IV hypersensitivity, which is involved in allergic phenomena and also in the pathogenesis of chronic inflammatory diseases, in particular following infection with a pathogenic agent (in particular leprosy, tuberculosis, leishmaniasis, listeriosis, etc.).
• a pathogenic agent in particular leprosy, tuberculosis, leishmaniasis, listeriosis, etc.
• Figure IA Nucleotidic and amino acid sequence of Mono28Fc, VH-CH2CH3 chain.
• Figure IB Nucleotidic and amino acid sequence of Mono28Fc, VL-CH2CH3 chain. Underlined: VL domain. Bold: linker. Double underlining: IgGl CH2-CH3 domains.
• Figure 1C Molecular constructions allowing the expression of Mono28Fc after transfection into eukaryotic host cells.
• pCMV promoter of the cytomegalovirus.
• Igk leader signal sequence from the mouse immunoglobulin kappa light chain.
• VH variable domain of the heavy chain of the CD28.3 antibody.
• VL variable domain of the light chain of the CD28.3 antibody.
• CH2 and CH3 represent the corresponding domains of the IgGl human immunoglobulin.
• Figure ID Expression plasmids for the synthesis of Mono28Fc in eukaryotic cells.
• A plasmid for the synthesis of the VH(Hc)-CH2-CH3 protein.
• B plasmid for the synthesis of the VL(Lc)-CH2-CH3 protein.
• pCMV promoter of the cytomegalovirus.
• Igk leader signal sequence from the mouse immunoglobulin kappa light chain.
• Hc VL variable domain of the heavy chain of the CD28.3 antibody.
• Lc VL variable domain of the light chain of the CD28.3 antibody.
• CH2 and CH3 represent the corresponding domains of the IgGl human immunoglobulin.
• BGH pA signal for the initiation of the 3' polyadenylation of the mRNA molecule, from the bovine growth hormone.
• Zeocin, ampicillin resistance genes for the corresponding antibiotic.
• Figure 2 Western blot analysis of pSecVHFc and pSecVLFc expression.
• A Supernatants from control, transfected or co -transfected Cos cells were added at the indicated dilutions, washed and revealed with rabbit anti-VH/VL antibodies plus anti-rabbit immunoglobulins-HRP.
• GFP negative control; transfection with an irrelevant GFP plasmid.
• Sc28AT positive control; transfection with a plasmid coding for a single-chain Fv against CD28.
• VLFc transfection with the pSec-VLFc plasmid.
• VHFc transfection with the pSec-VHFc plasmid.
• VH-(CH2-CH3) + VL-CH2-CH3 co-transfection with the pSec-VLFc and the pSec-VHFc plasmids.
• B Binding ELISA on recombinant CD28 of purified Mono28Fc molecules at the indicated concentration. Revelation is as in A. Dots are means of triplicates.
• Figure 4 Flow cytometry.
• CD28 + Jurkat T cells and CD28 " Raji B cells were incubated with purified Mono28Fc or with CD28.3 Fab fragments at 10 ⁇ g/ml for 30 min. at 4°C, washed and revealed with rabbit anti-VH/VH antibodies plus FITC-labeled goat anti-rabbit immunoglobulins (black profiles).
• As a control cells were incubated with rabbit anti-VH/VH antibodies plus FITC-labeled goat anti-rabbit immunoglobulins only (grey profiles). Cells were then washed, fixed and analyzed by Facs.
• Human PBMC (10 5 /well) were cultivated in medium or in medium plus 10 ⁇ g/ml Mono28Fc, sc28AT monovalent antibodies or with ANC28.1 superagonist antibodies for 3 days.
• 0.5 ⁇ Ci 3 H-tymidine was added for the last 16h of the culture.
• Incorporated radioactivity was evaluated on a scintillation counter after transfer on nitrocellulose membranes.
• Figure 7 Molecular constructions combining VH, VL with CH1-CH2-CH3 are nonfunctional.
• A RT-PCR analysis of the VH and VL mRNA chains expression after transfection of Cos cells.
• B Western blot analysis of supernatants (right panel) and lysates (left panel) of Cos cell transfected with pSecVH-CHl-CH2-CH3 and pSecVL-CHl-CH2- CH3 plasmids. Revelation was performed as in Figure 2.
• Figure 8 Amino acid sequence of Mono28Fc with IgG2 hinge and IgG4 CH2CH3 domains.
• VH-CH2CH3 chain Underlined: VH domain.
• Bold linker. Double underlining: IgG4 CH2-CH3 domains.
• Bold linker. Double underlining: IgG4 CH2-CH3 domains.
• CH2-CH3 domains of a human IgGl gene (NCBI Accession BCOl 8747) was amplified using the following primers introducing NheIIXbaI sites: CH2CH3-5':
• the resulting fragment was introduced into the pSC-A vector (Stratagene, Amsterdam, The Netherlands), resulting in the pSC-A-CH2-CH3 vector.
• VH and VL domains corresponding to the CD28.3 antibody anti-human CD28 were amplified from the previously described CNCM 1-2762 scFv cDNA (VANHOVE et al., Blood, 102, 564-70, 2003) and Nhel cloning sites were introduced by PCR with the following primers: VH:
• VH and VL fragments were cloned individually 5' to the CH2-CH3 domains into the Nhel site of the pSC-A-CH2-CH3 vector, resulting in VH- pSC-A-CH2- CH3 and VL- pSC-A-CH2-CH3 plasmids.
• the nucleotidic and amino acid sequences of the resulting VH-CH2CH3 and VL-CH2CH3 constructs are indicated respectively on Figures IA and IB. They are also indicated as SEQ ID NO: 1 and 3.
• COS cells were transfected separately with pSec-VH-Fc(CH2-CH3) (VH- Fc) or pSec-VL-Fc(CH2-CH3) (VL-Fc), or co-transfected with pSec-VH-Fc(CH2-CH3) and pSec-VL-Fc(CH2-CH3) or, as a control, transfected with a plasmid coding for an irrelevant green fluorescent protein (GFP), using the Fugene lipofection kit (Roche Diagnostics, Basel, Switzerland) according to the manufacturer's instructions. Cultures were maintained for 3 days at 37°C, divided one third, and put back into culture for an additional 3 days, after which time the cell supernatants were collected, electrophoresed in 10% polyacrylamide gels and blotted onto nitrocellulose membranes.
• GFP green fluorescent protein
• Blots were revealed with rabbit anti-CD28.3VH/VL (1 :5000 dilution) and an HRP-conjugated donkey antirabbit Ig antibody (Jackson Immuno-Research Laboratories) and developed by chemiluminescence (Amersham Pharmacia Biotech).
• EXAMPLE 3 DETECTION OF MONO28Fc BINDING ACTIVITY BY ELISA
• Recombinant human CD28 (R&D Systems, Abingdon, United Kingdom) was used at 1 ⁇ g/mL in borate buffer (pH 9.0) to coat 96-well microtiter plates (Immulon, Chantilly, VA) overnight at 4°C. These immobilized CD28 target molecules will bind only immunoreactive molecules with anti-CD28 activity.
• Reactive sites were blocked with 5% skimmed milk in PBS for 2 hours at 37°C and supernatants from control cells transfected with the plasmid coding for GFP, from cells transfected with only one of the plasmids pSec-VH-Fc(CH2-CH3) or pSec-VL-Fc(CH2- CH3), and from cells co-transfected with pSec-VH-Fc(CH2-CH3) and pSec-VL-Fc(CH2- CH3) were added at different dilutions and reacted for 2 hours at 37°C.
• Bound Fc fusion proteins with anti-28 activity were revealed with successive incubations (1 hour, 37°C) with rabbit anti-CD28.3VH/VL (1 :2000 dilution; custom preparation at Agrobio, La, France) and horseradish peroxidase (HRP)-conjugated donkey antirabbit Ig antibodies (1 :500 dilution; Jackson ImmunoResearch Laboratories, Bar Harbor, ME). Bound antibody was revealed by colorimetry using the TMB substrate (Sigma, L'Isle d'Abeau Chesnes, France) read at 450 nm. The results are shown on Figure 3 A.
• Mono28Fc was purified from culture supernatants of COS cells co- transfected with pSec-VH-Fc(CH2-CH3) and pSec-VL-Fc(CH2-CH3) and maintained for 3 days at 37°C. Supernatants were passed through G-Protein Sepharose columns
• EXAMPLE 4 DETECTION OF MONO28Fc BINDING ACTIVITY BY FLOW CYTOMETRY The binding of Mono28Fc was confirmed by flow cytometry using CD28+
• Jurkat human T cells which express CD28, or on Raji cells, a human B cell line that does not express CD28.
• Jurkat T cells or Raji cells were incubated for 1 hour at 4°C with purified Mono28Fc proteins or with Fab fragments of CD28.3 (VANHOVE et al., Blood, 102, 564-70, 2003), at 10 ⁇ g/ml for 30 min.
• As a control cells were incubated with rabbit anti-VH/VH antibodies plus FITC-labeled goat anti-rabbit immunoglobulins only.
• Bound Fc fusion monomers were detected with a rabbit anti-CD28.3VH/VL and a fluorescein isothiocyanate (FITC)-conjugated donkey anti-rabbit Ig antibody (dilution 1 :200; Jackson ImmunoResearch Laboratories) for 30 minutes at 4°C. Cells were then analyzed by fluorescence-activated cell sorting (FACS).
• FACS fluorescence-activated cell sorting
• Human PBMC (10 5 /well) were cultivated in culture medium without additive (control), or in culture medium with 10 ⁇ g/ml of mono28Fc, of sc28AT, or of ANC28.1 for 3 days.
• 0.5 ⁇ Ci 3 H-tymidine was added for the last 16h of the culture.
• Incorporated radioactivity was evaluated on a scintillation counter after transfer on nitrocellulose membranes. The results are shown on Figure 5.
• Recombinant proteins fused with an Fc fragment and immunoglobulins usually present an extended half-life in vivo because they are recognised by the FcRn receptor presented on endothelial and epithelial cells allowing the recycling of that molecules back in the circulation.
• FcRn receptor presented on endothelial and epithelial cells allowing the recycling of that molecules back in the circulation.
• the human IgGl CH1-CH2-CH3 cDNA was given by Dr. S. Birkle (Univ. France). It was inserted into the pcDNA3.1 into the Hind////Bam//7 restriction sites, resulting in the pcDNA3.1- CH1-CH2-CH3 plasmid.
• VH and VL domains corresponding to the CD28.3 antibody anti-human CD28 were amplified as described in Example 1 above, digested with the Nhe/ enzyme and inserted separately into the Nhe/ site of the pcDNA3.1- CH1-CH2-CH3 plasmid.
• VH- CH1-CH2- CH3 and VL- CH1-CH2-CH3 cassettes were then excised by EcoRV/Xbal digestion and inserted into the EcoR V digested pSecTag2B vector (Invitrogen), as disclosed in Example 1.

Landscapes

• Health & Medical Sciences (AREA)
• Immunology (AREA)
• Chemical & Material Sciences (AREA)
• Organic Chemistry (AREA)
• General Health & Medical Sciences (AREA)
• Life Sciences & Earth Sciences (AREA)
• Medicinal Chemistry (AREA)
• General Chemical & Material Sciences (AREA)
• Veterinary Medicine (AREA)
• Nuclear Medicine, Radiotherapy & Molecular Imaging (AREA)
• Bioinformatics & Cheminformatics (AREA)
• Pharmacology & Pharmacy (AREA)
• Engineering & Computer Science (AREA)
• Animal Behavior & Ethology (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Public Health (AREA)
• Biochemistry (AREA)
• Biophysics (AREA)
• Genetics & Genomics (AREA)
• Molecular Biology (AREA)
• Proteomics, Peptides & Aminoacids (AREA)
• Transplantation (AREA)
• Pulmonology (AREA)
• Pain & Pain Management (AREA)
• Rheumatology (AREA)
• Peptides Or Proteins (AREA)
• Preparation Of Compounds By Using Micro-Organisms (AREA)
• Micro-Organisms Or Cultivation Processes Thereof (AREA)
• Medicines Containing Antibodies Or Antigens For Use As Internal Diagnostic Agents (AREA)

Priority Applications (5)

Applications Claiming Priority (2)

Related Child Applications (2)

Publications (1)

Family

ID=40435756

Family Applications (1)

Country Status (5)

Cited By (3)

Families Citing this family (18)

Citations (6)

Family Cites Families (8)

• 2009
  • 2009-01-14 EP EP09290029A patent/EP2210902A1/en not_active Withdrawn
• 2010
  • 2010-01-13 US US13/144,471 patent/US9587023B2/en active Active
  • 2010-01-13 CA CA3037902A patent/CA3037902C/en active Active
  • 2010-01-13 JP JP2011545812A patent/JP5755148B2/ja active Active
  • 2010-01-13 EP EP10704185A patent/EP2387587A1/en not_active Withdrawn
  • 2010-01-13 CA CA2749627A patent/CA2749627C/en active Active
  • 2010-01-13 WO PCT/IB2010/000196 patent/WO2010082136A1/en not_active Ceased
• 2017
  • 2017-01-26 US US15/416,513 patent/US10689444B2/en active Active

Patent Citations (6)

Non-Patent Citations (11)

Also Published As

Similar Documents

Legal Events