摘要
在前期实验中,我们制备了一株抗CD20的嵌合抗体c8F6并证实其可有效杀伤CD20阳性的B淋巴瘤细胞。为了进一步降低c8F6的免疫原性,在研究中我们采用同源模建的方法模拟8F6的三维结构,通过分析其空间结构,确定可能影响抗体与抗原结合的框架区(FR)氨基酸残基,然后将鼠源抗体互补决定区(CDR)和FR区的关键氨基酸移植到人源模板上,构建出人源化抗体hu8F6。此人源化抗体除CDR区外,仅含有11个鼠源残基,但具有与嵌合抗体相似的亲和力和特异性。体外生物学功能实验进一步表明,hu8F6具有与c8F6相似的补体依赖的细胞溶解作用(CDC)和抗体依赖细胞介导的细胞毒作用(ADCC),可有效杀伤人B淋巴瘤细胞Raji和Daudi,提示hu8F6有望发展成为一个用于B淋巴瘤治疗的低免疫原性抗体制剂。
In our previous studies, a mouse/human chimeric anti-CD20 antibody-（c8F6） was prepared and it was demonstrated to be able to kill the CD20-positive B-lymphoma cells. To further minimize the immunogenicity of c8F6, here we attempted to constructed a humanized version of 8F6 and investigate its in vitro biological activities. Using a molecular model of 8F6 built by computer-assisted homology modeling, framework region （FR） residues of potential importance to the antigen binding were identified. Then, a humanized version of 8F6 was generated by transferring these mouse key FR residues and the mouse complementarity-determining region （CDR） residues onto the human antibody framework. This humanized antibody （hu8F6） retained only 11 murine residues outside of the CDRs, but was shown to possess affinity and specificity comparable to that of the chimeric version. Further studies showed that hu8F6 was as effective as e8F6 in mediating complement-dependent cytotoxicity （CDC） and antibody-dependent cellular cytotoxicity （ADCC） against human B-lymphoma cells Raji and Daudi, suggesting that it might be a promising therapeutic agent for Bcell lymphoma.
出处
《现代免疫学》
CAS
CSCD
北大核心
2009年第6期491-496,共6页
Current Immunology
基金
国家自然科学基金重点项目(30830109)
"重大新药创制"科技重大专项(2009ZX09503-009)
关键词
人源化
免疫原性
同源模建
单克隆抗体
8F6
humanization
immunogenicity
molecular modeling
monoclonal antibody
8F6
