阻断型抗人IgE单克隆抗体的制备及其表位分析

Preparation and identification of monoclonal antibodies against human IgE

目的利用基因重组抗原免疫小鼠，制备抗人IgE单克隆抗体，研究其特异性和功能。方法用表达的重组人IgE-Fc免疫BLAB／c小鼠，取其脾细胞与Sp2／o细胞融合，以间接ELISA法筛选杂交瘤上清。用ELISA阻断分析鉴定其生物学功能；通过丙氨酸突变扫描分析确定其抗原表位。结果利用杂交瘤技术获得了1株抗人IgE的单克隆抗体178，它具有IgE抗体特异性反应，其识别的抗原表位位于IgE与其受体结合的关键部位。经鉴定其具有体外阻断IgE与其受体结合的活性。结论利用基因重组抗原制备了1株抗人IgE的单克隆抗体178，此单克隆抗体具有体外阻断IgE与其受体结合的生物活性。

Objective To obtain monoclonal antibodies （McAb） against human IgE by recombi- nant IgE antigen. Methods BLAB/c mice were immunized with recombinant IgE. The spleen cells of immunized mice were used to prepare the McAb by hybridoma techniques. IgE-McAb was selected by indirect ELISA with culture supernaiant of hybridoma cells. ELISA blocking assay were employed to identify the function of McAb. Alanine scanning mutagenesis were used to confirm the antigenic epitopes of McAb. Resuits A monoclonal amibody against IgE（178） was produced. The antigenic epitope of 178 was found to be spatially close to the receptor-binding site. Functional assay revealed that 178 could markedly inhibit IgE binding to receptors. Conclusion A hybridoma cell line secreting IgE-McAb stably was obtained by recombinant IgE antigen, and the IgE-McAb might block IgE binding to receptors via steric hindrance.