Preparation and characterization of monoclonal antibody against human B7-H4 molecule.

B7-H4, a member of B7 family, is widely expressed in tumor tissues and plays an important role in the negative regulation of T cell immunity. In this study, we report on the establishment and characterization of a functional anti-human B7-H4 monoclonal antibody (MAb) 5G3 through hybridoma method. Flow cytometry analysis showed that MAb 5G3 specifically bound to B7-H4 molecule. Functional experiments indicated that MAb 5G3 could block the inhibitory role of B7-H4 molecule on A549 cells in and reduce the apoptosis of Jurkat cells, suggesting that MAb 5G3 is an antagonistic antibody and a useful tool for further studies of B7-H4 functions in cancers.