The Role of T-Cell Costimulatory Activation Pathways in Transplant Rejection

Organ transplantation is now common. For patients with end-stage cardiac, hepatic, or pulmonary failure, it can be lifesaving.1 For patients with diabetes mellitus, pancreatic transplantation offers the chance of a cure and the arrest or reversal of diabetic complications such as neuropathy and retinopathy. In 1996 more than 19,410 organ and tissue transplantations were performed in the United States, and 53,755 patients were on waiting lists for transplantation.Over the past two decades, the development of new immunosuppressive drugs with improved efficacy and decreased toxicity has led to substantial improvement in the survival of patients and in short-term graft survival . . .