A novel monoclonal antibody against mouse B7-H3 developed in rats.

B7-H3, a novel member of the B7 superfamily, plays a critical role during T cell activation; its functions are still unclear. In this study we obtained a novel anti-mouse B7-H3 monoclonal antibody (MAb) and characterized its biological functions. Our results demonstrated that this MAb could be used for flow cytometry and Western blot and immunohistochemistry analyses, suggesting that the performance of this MAb is much better than a commercial MAb (M3.2D7). Furthermore, data showed different expression profiles of mouse B7-H3 on various immune cells. We further showed that mouse B7-H3 protein was not expressed on normal tissues except for bladder epithelial cells using this MAb. Interestingly, the MAb could stimulate the proliferation and cytokine secretion of T cells. Taken together, this MAb might be of great value for further investigation of B7-H3 molecule.