抗人B因子单克隆抗体的制备及其特性的初步研究

本文以人B因子免疫BALB/c小鼠的脾细胞与SP2/O骨髓瘤细胞融合,获得六株(A_2、B_2、B_7、C_9、F_9、F_(10))分泌抗人B因子单克隆抗体(单抗)的杂交瘤细胞系。用ELISA检测细胞培养上清和小鼠腹水的特异性抗体效价,分别为10~(-2)—10~(-3)和10~(-4)—10~(-5)。抗原阻断试验结果,说明这些单抗是B因子特异的。经取代试验和ACH_(50)抑制试验,提示B因子具有耐热和不耐热二组抗原决定基。A_2和B_2针对不耐热抗原决定基,能抑制补体旁路途径活化;B_7和C_9针对耐热抗原决定基,不影响补体旁路途径活化;F_9和F_(10)则既能与耐热决定基发生反应,也具有抑制补体旁路活化的功能。用固相抗原竞争抑制试验,分析B因子的抗原表位,发现6株单抗可识别4个抗原决定基。这些单抗对B因子结构与功能的研究,B因子在补体旁路活化过程中与有关补体成分之间的相互关系的研究,都是很有意义的。

The Study of Prepation and Characterization of McAb against Human Factor B

This paper reported the preparation of McAb against human factor B by fusing spleen cells of BALB/C mice immunized with purified human factor B with mouse myeloma line sp2/0.Six hybridoma cell lines secreting antihuman factor B McAbs were obtained. The titers of specfic antibody of culture supernatants and mouse (ascites were 10-2 10-3 and 10-4-10-5 respectively by solid phase ELISA. Antigen blocking test proved that these McAbs reacted specifically with human factor B. Results of inactivated human factor B substition test and ACH50 inhibition test suggested that factor B had two groups of antigenic determinants, the heat labile and the heat resistant.A2 and B2 could react with heat labile determinants and inhibit the activation of alternative pathway; BT and C9 were specific to heat resistant dererminant but had no effect on activation of alternative pathway. The other McAb (F9 and F1O) reacted with heat resistant determinant as well as inhibited the activation of alteinative pathway.Analysis of antigenic determinant of factor B by solid phase antigen competitive inhibition test revealed that the six McAbs could recognize four determinants of factor B.We consider that these McAbs may be very important in the study of the structure and function of factor B. Th se McAbs may also be useful for the study of the interaction between factor B and relative complement components during the activation of alternative pathway.