抗日本血吸虫单克隆抗体NP11-4人/鼠嵌合Fab抗体片段的制备及功能鉴定

目的:构建日本血吸虫单克隆抗体NP11-4的人/鼠嵌合Fab(cFab)抗体片段,并对cFab抗体片段结合活性进行鉴定.方法:用抗体框架区的通用引物PCR扩增抗日本血吸虫单克隆抗体NP11-4的VH及VL基因,测序分析其核苷酸序列.将测序正确的鼠源VH、VL分别与人IgG1的CH1、CL通过Overlap PCR扩增Fd及全长L,再利用Overlap PCR以Fd和全长L基因为模板扩增cFab基因.将cFab基因片段克隆至载体pComb3XSS中构建表达载体pComb3XSS-Fab,经异丙基-β-D-硫代半乳糖苷(IPTG)诱导进行蛋白可溶性表达.通过Western blot和ELISA方法对cFab抗体片段进行检测.结果:构建出抗日本血吸虫单克隆抗体NP11-4 cFab表达载体,Western blot结果证实在大肠杆菌Top10F'中表达出cFab可溶性抗体片段,ELISA结果显示cFab抗体片段与可溶性虫卵抗原(SEA)有较好的结合活性.结论:表达、纯化了抗日本血吸虫单克隆抗体NP11-4 cFab抗体片段,cFab抗体片段具有与亲本抗体相同的抗原结合能力,为制备抗日本血吸虫人源化免疫毒素提供了技术贮备.

Construction,expression and characterization of chimeric mouse-human Fab of monoclonal antibody NP11-4 against Schistosomiasis japonica

Objective:To construct chimeric mouse-human Fab antibody from a mouse monoclonal antibody NP11-4 which is specific to membrane protein of Schistosoma japonicum by genetic engineering technique,and further identify the binding ability of chimeric antibody fragment. Methods:Light chain variable region(VL) and heavy chain variable region(VH) genes cloned from mouse monoclonal antibody NP11-4 were amplified by RT-PCR,and sequenced and analyzed after being ligated into pMD18-T vector. Then VH and VL were fused i...