Preparation Of Mouse-anti-human FL Monoclonal Antibodies And Study Of Their Biological Functions

ObjectiveTo prepare monoclonal antibodies against human FL molecule and analysis of their biological characteristics.MethodsThe BALB/c mice were immunized with the transfected cell line L929/FL that expressed membrane FL. The splenocytes from the immunized mice were fused with myeloma cell line SP2/0, and then the hybridoma cells were screened with immunostaing and FCM. The isotype of the monoclonal antibody identified by rapid isotyping analysis, and the FL expression profile on tumor cell lines was analyzed by indirect immunofluorescence with mAb 3E5. To analysis the biological function of mAb 3E5, we added the 3E5 to the RPMI1640 medium containing FL protein to culture THP-1 cells.ResultsThree hybridoma cell lines named 5H5, 5D1, 3E5 were obtained, which had the property of secreting anti-human FL monoclonal antibody continuously and steadily. Fast-strip method analysis displayed that these mAbs belonged to mouse IgG1,κ(3E5) and IgM,κ(5H5,5D1) subclass, respectively.Ascites were induced to produce the monoclonal antibody and 2.0 ml ascites was obtained from each BALB/c mouse on average. FL protein could enhance the proliferation of U937, 675321, THP-1, and it could be neutralized by 3E5 mAb. ConclusionOur study established three anti-human FL mAbs, one of them (3E5) is a neutralized FL mAb and provided a useful tool for studying the biological function of FL.