中国免疫学杂志2009，Vol.25Issue(11)：1003-1005,3.
重症肌无力治疗性单价IgG抗体基因的构建
Construction of a monovalent IgG antibody gene for therapy of myasthenia gravis
摘要
Abstract
Objective:To construct a monovalent IgG antibody gene for specific immunotherapy of myasthenia gravis.Methods:A pathogenic anti-human acetylcholine receptor (AChR) antibody IgG637,previously developed in our laboratory,was mutated in the site of K322A to remove the complement binding activity,and 4 amino acids (PLKP) were deleted in complemetary determining region 3 (CDR3) to remove the specific antigen binding activity by site-directed mutagenesis technology.The genes of mutant IgG637/K322A and IgG637/K322A/CDR3ΔPLKP were then transformed respectively into E.coli XL1-Blue for cloning,sequencing and furthermore transinfected into mammalian cell line CHO-k1 for expression.The complement C3-binding activity of expressed product IgG637/K322A was determined in ELISA,and the human AChR-binding activity of IgG637/K322A/CDR3ΔPLKP in RIA.The mutant antibody genes were further undergone mutation of knob (T366Y) and hole (Y407T) to favor the heterodimerization of H chain in making monovalent IgG antibody.Results:The mutant IgG637/K322A was not able to bind complement C3 in ELISA,and the mutant IgG637/K322A/CDR3ΔPLKP was not able to bind the specific antigen human AChR in RIA.The correct mutations of knob and hole were observed by sequencing.Conclusion:The genes of monovalent IgG anti-AChR antibody without complement-binding activity are successfully developed from a pathogenic anti-AChR antibody IgG637.关键词
重症肌无力/单价抗体/定点突变/免疫球蛋白GKey words
Myasthenia gravis/ Monovalent antibody/ Site-directed mutagenesis/ IgG分类
医药卫生引用本文复制引用
李钟燮,孟繁平,孙昌元,李芳芳,金权鑫,李红花,李英信,M.Stassen,M.de Baets..重症肌无力治疗性单价IgG抗体基因的构建[J].中国免疫学杂志,2009,25(11):1003-1005,3.基金项目
本文为国家自然科学基金资助项目(No.30760234、30860260) （No.30760234、30860260）
