抗人C1q单克隆抗体的作用部位及对C1q功能影响的研究

为了研究抗人C_1单克隆抗体(McAb)A_4、B_6、D_5的作用部位及对C_1q功能的影响,本文采用免疫印渍技术观察了McAb A_4、B_6、D_5和C_1q的A、B、C链及胶原样区域的反应性,通过C_1q溶血试验观察了McAbs对游离C-1q、EAC_1q和血清C_1溶血活性的影响。实验结果表明,McAb A_4、B_6、D_5的作用部位均位于C_1q的B和C链的胶原样区域中,各McAbs对游离C_1q,EAC_1q,血清C_1溶血活性均有不同程度的抑制作用。McAbD_5对血清C_1溶血活性的抑制作用明显高于对游离C_1q,EAC_1q的抑制作用。此结果可能提示:C_(1r)、C_(1s)和C_1q结合成C_1分子使C_1q构象发生改变,暴露了新抗原。

Study on the Reactive Sites of the Monoclonal Antibodies to Human Clq and the Effects of the Antibodies on the Function of Clq

In order to determin the reactive sites of the monoclonal antibodies directed to human Clq, named A4, Be. D5, and the effects of these antibodies on the function of Clq, the reactivities of the A, B, C chains and the collagen-like fre-gment of Clq to the monoclonal antibodies were observed through immunoblot-ting,the effects of the A4, Be and D5 on the hemolytic activities of free Clq, cell-bound Clq and Cl in serum were also observed with Clq and Cl hemolytic assays.The results showed that the reactive sites of A4,B6,D5 are located in the collagen-like region of B and C chains of Clq and that these antibodies inhibit the hemolytic activities of free Clq cell-bound Clq and Cl in serum with different degree. Ds.has much stronger inhibitory effect on Cl in serum than that on free Clq and cell-bound Clq. This resulty suggests that the conf-ormational change in Clq molecule occur upon binding of Clr and Cls to Clq, which leads to formation of neoantigen.