Belatacept (BMS 224818) is a selective T-cell costimulation blocker and a costimulator of the CD28-CD80/86 pathway. Belatacept binds to the CD 80/86 ligand and inhibits CD-28-mediated T cell costimulation and IFN-γ production. Belatacept can be used in studies of immunosuppression in organ transplantation. The component ratio of this product is Active ingredient : Excipients = 1:2.4.