CTLA4Ig融合蛋白在CHO细胞中的表达  

Expression of CTLA4Ig fusion protein in CHO cells

作　　者：陈兴[1] 于继云[1] 沈倍奋[1] 黎燕[1] 王嘉玺[1] 程绍辉[1] 贺永怀[1] 曲梅花[1] 胡美茹[1] 孙瑛勋[1] 于鸣[1] 

机构地区：[1]军事医学科学院基础医学研究所,北京100850

出　　处：《生物技术通讯》2004年第4期357-358,共2页Letters in Biotechnology

基　　金：国家自然科学基金(30080026)

摘　　要：CTLA4Ig是人CTLA4胞外区与人免疫球蛋白铰链区、CH2区、CH3区组成的融合蛋白,可以与B7结合,通过阻断B7与CD28的结合,从而阻断B7介导的T细胞活化必需的共刺激信号,可作为免疫抑制剂用于器官移植。将CTLA4Ig融合分子克隆到真核表达载体pCI-dhfr,并用脂质体方法转染到COS7和CHO-dhfr-细胞中,用氨甲喋呤筛选转染的CHO-dhfr-细胞。用RT-PCR、ELISA、细胞免疫荧光染色和Western-blot鉴定重组蛋白的表达。采用A蛋白纯化重组蛋白。CTLA4Ig is a soluble chimeric protein consisting of extracellular domain of human CTLA4Ig and a fragment (hinge,CH2,and CH3domains)of the Fc of human IgG1.CTLA4Ig binds to B7molecules on APCs and thereby blocks the B7mediated co-stimulatory signal for T-cell activation and so may be used as immunosuppressant in organ transplan-tation.In this study,CTLA4Ig chimeric molecule was cloned into eukaryotic expression vector pCI-dhfr.Using lipofectine-mediated gene transfer technique,pCI-CTLA4Ig was transfected into CHO-dhfr-cell,and the transfectants were selected with methotrexate.Expression of the recombinant protein was assessed by PR-PCR,ELISA,cell immunofluorescense stain-ing and Western-blot,and at last the recombinant protein purification was performed by protein A chromatography.

关 键 词：CTLA4Ig融合蛋白 CHO细胞 表达 免疫抑制剂 

分 类 号：Q786[生物学—分子生物学] R392.11[医药卫生—免疫学]