FIG 1.
Schematic depiction of the structure of human IgG1, IgG3, and the IgG3m17 and IgG3m15 mutant antibodies. The length and amino acid sequence of the hinge region of the IgG3 variants are also shown. The functional hinge consists of the upper hinge, which is from the end of the CH1 domain to the N-terminal S-S bridge (cystine); the core hinge, which is from the N-terminal S-S bridge to the end of the beginning of the CH2 domain; and the lower hinge, which is the 8 N-terminal amino acids of the CH2 domain (47, 60). The genetic hinge consists of the upper hinge and the core hinge. Gray, the constant κ light chains; green, the constant IgG1 heavy chains; blue, the constant IgG3 heavy chains; orange, variable regions.