抗人CTLA-4单克隆抗体的制备及其生物学活性研究

以我室用基因工程表达的人CTLA 4蛋白[1,2 ] 作为免疫原 ,采用细胞融合、ELISA法和免疫印迹等方法制备并筛选到鼠抗人CTLA 4的单克隆抗体 ,并以单向混合淋巴细胞刺激反应 (MLR )测定了抗人CTLA 4抗体对淋巴细胞增殖的影响。结果表明我们得到了 4株单克隆抗体 (1H7、 2G2、 2F11、 3A7) ,它们均可与近似天然构象的人CTLA 4Ig融合蛋白结合 ,又可与大肠杆菌表达出的经复性后的人CTLA 4蛋白结合 ,并且可分别识别人CTLA 4Ig融合蛋白不同抗原决定簇。其中一株(3A7)既和近似天然构象的蛋白结合又可与变性的蛋白结合 ,并具有显著阻断CTLA 4的抑制性免疫信号传递 ,促进同种异体混合淋巴细胞增殖的功能

Preparation of Anti-human CTLA-4 Monoclonal Antibody and Study on Their Biological Activities

The mouse derived anti human CTLA 4 monoclonal antibodies were produced in this laboratory by using expressed human CTLA 4 protein as immunogen,and 4 monoclonal antibodies designated as 1H7,2G2,2F11 and 3A7 were produced,screened and confirmed by ELISA (indirect,sandwich and competitive ELISA) and immunoblotting method The results showed that all these 4 monoclonal antibodies could bind with both the human CTLA 4 Ig fusion protein with similarly natural conformation and the renatured human CTLA 4 recombinant protein These 4 monoclonal antibodies could also recognize the different epitopes on the human CTLA 4Ig fusion protein The 3A7 monoclonal antibody could specifically bind with both the proteins with natural conformation and the renatured proteins,and also block the inhibitiory signal transduction of CTLA 4,thus notably promote the proliferation of allogenic cells in the mixed lymphocytes reaction