Understanding the regulatory events involved in the activation and inactivation of T cells is
crucial to develop therapeutic approaches for autoimmune diseases and for organ
transplantation. Co‐stimulatory signals delivered through the CD28 receptor and inhibitory
signals through CTLA‐4 are required for the proper modulation of T cell responses and the
induction and maintenance of peripheral tolerance. Manipulation of these signals is
emerging as a potential strategy to prevent allograft rejection in different animal models …