Antibodies of the class IGG4
The present invention provides an antibody of the class IgG4 comprising at least one heavy chain which comprises a C H 1 domain and a hinge region, wherein in each heavy chain: a. the inter-chain cysteine at position 127, numbered according to the Kabat numbering system, in the C H 1 domain is substituted with another amino acid; and b. one or more of the amino acids positioned in the upper hinge region is substituted with cysteine.
1. An antibody of the class IgG4, comprising two light chains and two heavy chains, wherein the heavy chains comprise a C H 1 domain and a hinge region comprising an IgG4 upper hinge and core region, wherein in each heavy chain:
(a) the inter-chain cysteine at position 127 in the C H 1 domain is substituted with an amino acid selected from the group comprising serine, threonine, alanine, and glycine; and
(b) one or more of the amino acids at positions 227, 228, and 229 in the upper hinge region is substituted with cysteine,
and wherein the amino acid numbering is according to the Kabat numbering system.
2. The antibody of claim 1 , wherein the amino acid at position 229 is cysteine.
3. The antibody of claim 1 , wherein the amino acid at position 228 is cysteine.
4. The antibody of claim 1 , wherein the amino acid at position 227 is cysteine.
5. The antibody of claim 1 , wherein at least one of the amino acids at position 239 and position 242, numbered according to the Kabat numbering system, in each of the heavy chains is a serine.
6. The antibody of claim 1 , wherein the amino acid at position 239, numbered according to the Kabat numbering system, in each of the heavy chains is serine.
7. The antibody of claim 1 , wherein the amino acid at position 242, numbered according to the Kabat numbering system, in each of the heavy chains is serine.
8. The antibody of claim 7 , wherein the amino acid at position 239 and/or the amino acid at position 242 is a serine.
9. The antibody of claim 1 , wherein the heavy chains are mutated to insert three amino acids between amino acids 226-243, numbered according to the Kabat numbering system.
10. The antibody of claim 9 , wherein the heavy chains are mutated to insert three amino acids between positions 238 and 239, numbered according to the Kabat numbering system.
11. The antibody of claim 10 , wherein three alanines are inserted between positions 238 and 239, numbered according to the Kabat numbering system.
12. The antibody of claim 10 , wherein a threonine, a histidine and a further threonine are inserted between positions 238 and 239, numbered according to the Kabat numbering system.
13. The antibody of claim 10 , wherein the serine at position 241, numbered according to the Kabat numbering system, is substituted with proline.
14. The antibody of claim 1 , wherein each heavy chain comprises a CH2 domain and a CH3 domain.
15. The antibody of claim 1 , wherein the heavy chains are identical.
16. The antibody of claim 1 , wherein the upper hinge and core region is of 15 amino acids in length.
17. The antibody of claim 1 , wherein the upper hinge and core region is 13-17 amino acids in length.
18. The antibody of claim 1 , wherein the inter-chain cysteine at position 127 is substituted with a threonine or serine.
19. The antibody of claim 1 , wherein the inter-chain cysteine at position 127 is substituted with a serine.