Interchain Disulfide Bonding in Human IgG2 Antibodies Probed by Site-Directed Mutagenesis

详细信息    查看全文

• 作者：Martin J. Allen ; Amy Guo ; Theresa Martinez ; Mei Han ; Gregory C. Flynn ; Jette Wypych ; Yaoqing Diana Liu ; Wenyan D. Shen ; Thomas M. Dillon ; Christopher Vezina ; Alain Balland
• 刊名：Biochemistry
• 出版年：2009
• 出版时间：May 5, 2009
• 年：2009
• 卷：48
• 期：17
• 页码：3755-3766
• 全文大小：366K
• 年卷期：v.48,no.17(May 5, 2009)
• ISSN：1520-4995

文摘

Human IgG2 exists as a mixture of disulfide-linked structural isoforms that can show different activities. To probe the contribution of specific cysteine residues to the formation of structural isoforms, we characterized a series of Cys→Ser mutant IgG2 recombinant monoclonal antibodies, focused on the first C_H1 cysteine and the first two hinge cysteines. These residues participate in the formation of structural isoforms that have been noted by nonreduced capillary sodium dodecyl sulfate polyacrylamide gel electrophoresis, reversed-phase high-performance liquid chromatography, and cation exchange chromatography. We show that single Cys→Ser mutants can greatly reduce heterogeneous disulfide bonding in human IgG2 and maintain in vitro activity. The data demonstrate the feasibility of applying site-directed mutagenesis to reduce disulfide bond heterogeneity in human IgG2 while preserving the activity of this therapeutically important class of human antibodies.