Blood transfusions, suppressor T cells, and renal transplant survival

Fifteen men undergoing chronic hemodialysis were transfused with 2 units of packed red cells, none of these patients having been previously transfused. They were studied before and after transfusion to determine suppressor T cell numbers and activity, and to monitor the appearance of cytotoxic antibodies. Although the number of suppressor T cells did not change, their function was significantly increased three weeks after the transfusion. This had largely returned to normal by 20 weeks. No cytotoxic antibodies were produced. Twelve of the patients subsequently received cadaveric renal transplants and nine of these kidneys are currently functioning more than a year after transplantation. Although the blood transfusions may have helped to produce these satisfactory results, it is accepted that the nonspecific increase in suppressor cell function may not have been the only mediator because this activity had returned to normal in most cases by the time the patients were transplanted.