4株鼠抗人B7-1分子单抗的制备及其生物学活性的鉴定

目的：制备鼠抗人B7—1分子(mAb)单抗及研究其生物学活性。方法：以人多发性骨髓瘤细胞转人B7-1基因细胞株XG7-B7为免疫原，采用B淋巴细胞杂交瘤技术制备鼠抗人B7—1分子单抗；以Western blot及间接免疫荧光标记法鉴定其特异性和亲和力；采用^3H—TdR掺入实验和Annexin-Ⅴ染色分析测定该单抗的生物学功能。结果：获得了4株持续分泌抗人B7—1分子的特异性单抗的杂交瘤细胞株，分别命名为1F11、3H8、6H2和7B10，其分泌的单抗类别分属于小鼠IgG1和IgM；4株单抗均具有良好的特异性和亲和力；1F11、3H8和6H2能部分组断B7—1分子基因转导细胞介导的共刺激信号，从而抑制T细胞的增殖效应(抑制率21％—52％)；且能诱导天然表达B7—1分子的人B系淋巴瘤细胞Raji的凋亡。结论：成功研制4株功能性抗人B7—1分子抗体，这些抗体在抗异体组织器官移植排斥反应及在B系淋巴瘤的治疗中具有潜在的应用价值。

Preparation of four monoclonal antibodies against human B7-1 and analysis of their biological characteristics

Objective:To prepare the monoclonal antibody(mAb) against human B7 1 and analyse its biological characteristics.Methods:The B lymphocytes hybridization technique was applied by using XG7 B7 cell,a multiple myeloma(MM) cell line transfected with human B7 1 gene,as immunogen;the specificity and the antigen binding activity of mAbs were identified by flow cytometry and Western blot analysis;its biological effects on human PBTC and human B lymphoma cell line were examined by 3H TdR incroporation and annexin V satining.Results:Four mouse anti human B7 1(B7 1) hybridoma(1F11,3H8,6H2,7B10) were obtained.They secrete continuosly and steadily specific anti human B7 1(B7 1) mAb and their subclasses belong to IgG1 and IgM respectively;three of four mAbs could inhibit the proliferation of response cells(the human peripheral blood T lymphocytes),stimulated by costimulatory molecule B7 1.Furthermore,it was found that these mAbs induced the apoptosis of human B lymphoma cell line,Raji,which express naturally human B7 1 molecule,by using annexin V staining analysis after 24 hours of mAb treatment.Conclusion:Sucessefully obtained four mouse anti human B7 1 functional monoclonal antibodies,which have a potential value in anti allogenetic graft rejection and in the therapeutic approach of B lymphoma.