Previous studies have also shown that blocking both CD28 and CD154 costimulatory pathways prevents autoimmune diabetes induced by transfer of transgenic T cells in NOD.SCID mice [28] but fails to induce long-term islet allograft survival in NOD recipients [29], suggesting that CD28/CD154 blockade is sufficient to suppress autoimmunity but insufficient to simultaneously suppress both alloimmunity and autoimmunity in NOD recipients. Here, CD28 is linked to Autoimmunity.