Antibodies comprising chimeric constant domains
Antibodies, antigen-binding proteins and Fc-fusion proteins that comprise recombinant polypeptides containing a chimeric heavy chain constant region sequence are provided that bind to certain Fc receptors however have reduced effector functions. Methods of making constructs for expression of such chimeric Fc-containing antibodies, antigen-binding proteins and Fc-fusion proteins in cell systems, and methods of producing and isolating the chimeric Fc-containing proteins are provided.
1. An antibody comprising a heavy chain constant (CH) region comprising, from N-terminus to C-terminus, a CH1 domain, a hinge, a CH2 domain, and a CH3 domain wherein:
(a) the CH1 domain comprises a human IgG1 CH1 domain or a human IgG4 CH1 domain having the amino acid sequence DKKV or DKRV from positions 212 to 215 (EU numbering),
(b) the hinge comprises a human IgG1 or a human IgG4 upper hinge amino acid sequence from positions 216 to 227 (EU numbering) and a human IgG2 lower hinge amino acid sequence PCPAPPVA (SEQ ID NO: 3) from positions 228 to 236 (EU numbering),
(c) the CH2 domain comprises a human IgG4 CH2 domain amino acid sequence from positions 237 to 340 (EU numbering), and
(d) the CH3 domain comprises a human IgG1 or a human IgG4 CH3 domain sequence from positions 341 to 447 (EU numbering), and
wherein the antibody is capable of binding to an FcγR with lower affinity than a corresponding antibody comprising a wild-type IgG1 or wild-type IgG4 heavy chain constant region, the antibody is capable of binding FcγRIIA and optionally FcγRIIB, and the antibody is capable of binding FcγRIIA with higher affinity compared to its binding affinity to FcγRIIB.
2. Nucleic acid molecules encoding an antibody of claim 1 .
3. A vector comprising the nucleic acid molecules of claim 2 .
4. A cell comprising the nucleic acid molecules of claim 2 .
5. An Fc-fusion protein comprising a heavy chain constant (CH) region comprising, from N-terminus to C-terminus, a CH1 domain, a hinge, a CH2 domain, and a CH3 domain wherein:
(a) the CH1 domain comprises the amino acid sequence DKKV or DKRV from positions 212 to 215 (EU numbering),
(b) the hinge comprises a human IgG1 or a human IgG4 upper hinge amino acid sequence from positions 216 to 227 (EU numbering) and a human IgG2 lower hinge amino acid sequence PCPAPPVA (SEQ ID NO: 3) from positions 228 to 236 (EU numbering),
(c) the CH2 domain comprises a human IgG4 CH2 domain amino acid sequence from positions 237 to 340 (EU numbering), and
(d) the CH3 domain comprises a human IgG1 or a human IgG4 CH3 domain sequence from positions 341 to 447 (EU numbering), and
wherein the Fc-fusion protein is capable of binding to an FcγR with lower affinity than a corresponding Fc-fusion protein comprising a wild-type IgG1 or wild-type IgG4 heavy chain constant region, the Fc-fusion protein is capable of binding FcγRIIA and optionally FcγRIIB, and the Fc-fusion protein is capable of binding FcγRIIA with higher affinity compared to its binding affinity to FcγRIIB.
6. A nucleic acid molecule encoding an Fc-fusion protein of claim 5 .
7. A vector comprising the nucleic acid molecule of claim 6 .
8. A cell comprising the nucleic acid molecule of claim 6 .
9. A bispecific antibody comprising:
(a) a first heavy chain comprising an antigen-binding domain capable of recognizing and binding to a first target antigen,
(b) a second heavy chain comprising an antigen-binding domain capable of recognizing and binding to a second target antigen, and
(c) a common light chain antigen-binding domain capable of recognizing and binding to the first or second target antigen,
wherein the heavy chain of (a) or (b) or both (a) and (b) comprises a chimeric IgG4 heavy chain constant (CH) region comprising an IgG4 CH1 domain, an IgG4 upper hinge from positions 216 to 227 (EU numbering), an IgG2 lower hinge from positions 228 to 236 (EU numbering), an IgG4 CH2 domain, and an IgG4 CH3 domain, or the heavy chain of (a) or (b) or both (a) and (b) comprises a chimeric IgG1 CH region comprising an IgG1 CH1 domain, an IgG1 upper hinge from positions 216 to 227 (EU numbering), an IgG2 lower hinge from positions 228 to 236 (EU numbering), an IgG4 CH2 domain, and an IgG1 CH3 domain,
wherein the bispecific antibody is capable of binding to an FcγR with lower affinity than a corresponding bispecific antibody comprising a wild-type IgG1 or wild-type IgG4 heavy chain constant region, the bispecific antibody is capable of binding FcγRIIA and optionally FcγRIIB, and the bispecific antibody is capable of binding FcγRIIA with higher affinity compared to its binding affinity to FcγRIIB.
10. Nucleic acid molecules encoding a bispecific antibody of claim 9 .
11. A vector comprising the nucleic acid molecules of claim 10 .
12. A cell comprising the nucleic acid molecules of claim 10 .
13. A method of making an antibody, said method comprising:
(a) transfecting a host cell with a nucleic acid molecule encoding a light chain of said antibody, said nucleic acid molecule comprising a nucleotide sequence encoding the V L region of a selected antigen-specific antibody and a nucleotide sequence encoding the constant C L region of an Ig, wherein said nucleotide sequence encoding the V L region of a selected antigen-specific antibody and said nucleotide sequence encoding the C L region of an Ig are operably linked together;
(b) transfecting the host cell of step (a) with a nucleic acid molecule encoding a heavy chain of said antibody, said nucleic acid molecule comprising a nucleotide sequence encoding the V H region of a selected antigen-specific antibody and a nucleotide sequence encoding a constant C H region of a human Ig, wherein the nucleotide sequence encoding the C H region comprises the nucleotide sequence encoding SEQ ID NO: 1, SEQ ID NO: 2, SEQ ID NO: 30, SEQ ID NO: 31, SEQ ID NO: 37 or SEQ ID NO: 38, wherein said nucleotide sequence encoding the V H region of a selected antigen-specific antibody and said nucleotide sequence encoding the C H region of said Ig are operably linked together; and
(c) making said antibody by co-expressing the nucleic acid molecules of (a) and (b) in said host cell, wherein the host cell is cultured and the antibody is secreted into a cell culture medium; and
(d) isolating the antibody from the cell culture medium,
wherein the antibody is capable of binding to an FcγR with lower affinity than a corresponding antibody comprising a wild-type IgG1 or wild-type IgG4 heavy chain constant region, the antibody is capable of binding to FcγRIIA and optionally FcγRIIB, and the antibody is capable of binding to FcγRIIA with higher affinity compared to its binding affinity to FcγRIIB.
14. A method of making an Fc-fusion protein, said method comprising:
(a) transfecting a host cell with a nucleic acid molecule encoding said Fc-fusion protein, said nucleic acid molecule comprising a nucleotide sequence encoding a protein, fused to a nucleotide sequence encoding a constant C H region of a human Ig, wherein the nucleotide sequence encoding the C H region comprises the nucleotide sequence encoding SEQ ID NO: 1, SEQ ID NO: 2, SEQ ID NO: 30, SEQ ID NO: 31, SEQ ID NO: 37 or SEQ ID NO: 38, wherein said nucleotide sequence encoding the protein and said nucleotide sequence encoding the C H region of said Ig are operably linked together; and
(b) making said Fc-fusion protein by expressing the nucleic acid molecule of (a) in said host cell, wherein the host cell is cultured and the Fc-fusion protein is secreted into a cell culture medium; and
(c) isolating the Fc-fusion protein from the cell culture media,
wherein the Fc-fusion protein is capable of binding to an FcγR with lower affinity than a corresponding Fc-fusion protein comprising a wild-type IgG1 or wild-type IgG4 heavy chain constant region, the Fc-fusion protein is capable of binding to FcγRIIA and optionally FcγRIIB, and the Fc-fusion protein is capable of binding to FcγRIIA with higher affinity compared to its binding affinity to FcγRIIB.
15. A composition comprising the antibody of claim 1 , and a pharmaceutically acceptable carrier or diluent.
16. A bispecific antibody, comprising:
(a) a first heavy chain comprising an antigen-binding domain capable of recognizing and binding to a first target antigen,
(b) a second heavy chain comprising an antigen-binding domain capable of recognizing and binding to a second target antigen, and
(c) a common light chain antigen-binding domain capable of recognizing and binding to the first or second target antigen,
wherein the heavy chain of (a) or (b) or both (a) and (b) comprises the heavy chain constant region comprising a hinge comprising a human IgG1 or a human IgG4 upper hinge amino acid sequence from positions 216 to 227 (EU numbering) and a human IgG2 lower hinge amino acid sequence PCPAPPVA (SEQ ID NO: 3) from positions 228 to 236 (EU numbering).
17. A method of killing a target cell via antibody-dependent cellular phagocytosis, comprising contacting the target cell with an antibody comprising a variable region that binds an antigen on the target cell and a heavy chain constant region, wherein the heavy chain constant region comprises a hinge comprising a human IgG1 or a human IgG4 upper hinge amino acid sequence from positions 216 to 227 (EU numbering) and a human IgG2 lower hinge amino acid sequence PCPAPPVA (SEQ ID NO: 3) from positions 228 to 236 (EU numbering).
18. The method of claim 17 , wherein the target cell is a tumor cell.
19. A method of making an antibody with decreased antibody-dependent cellular cytotoxicity (ADCC), comprising combining a variable region with a heavy chain constant region, wherein the heavy chain constant region comprises a hinge comprising a human IgG1 or a human IgG4 upper hinge amino acid sequence from positions 216 to 227 (EU numbering) and a human IgG2 lower hinge amino acid sequence PCPAPPVA (SEQ ID NO: 3) from positions 228 to 236 (EU numbering), wherein the antibody exhibits undetectable ADCC activity as measured in an in vitro or ex vivo cell killing assay at an antibody concentration of 100 nM.
20. A method of making an antibody that does not bind to human FcγRI or human FcγRIII, comprising combining a variable region with a heavy chain constant region, wherein the heavy chain constant region comprises a hinge comprising a human IgG1 or a human IgG4 upper hinge amino acid sequence from positions 216 to 227 (EU numbering) and a human IgG2 lower hinge amino acid sequence PCPAPPVA (SEQ ID NO: 3) from positions 228 to 236 (EU numbering), wherein the antibody exhibits undetectable binding to His-captured FcγRI and FcγRIII as measured in a surface plasmon resonance assay at 25° C.