Bone marrow transfusions in cadaver renal allografts: pilot trials with concurrent controls

Background: The safety and immune tolerance potential of donor marrow infusion with cadaveric source renal transplants was evaluated in a series of non-randomized multicenter pilot trials by the NIH Cooperative Clinical Trials in Transplantation (CCTT) Group. Patients and methods: Three strategies were tested: (1) immunosuppression with cyclosporin, azathioprine and prednisone with a single post-transplant day 1 infusion of 5 × 107 viable cells/kg, (2) OKT3 induction with triple drug therapy and marrow transfusion on day 1, or (3) same therapy as (2) but with an additional marrow transfusion on day 10–12. Results: Thirty-eight marrow recipients and 35 contemporaneous controls were entered with a mean follow-up of over 5 yr. Graft survival was initially better in the marrow recipients than the controls but was similar after 5 yr. Microchimerism rates were similar for the marrow infusion and control groups throughout the follow-up period, regardless of the immunosuppression strategies. Discussion: Bone marrow infusions were well tolerated by a group of cadaver renal allograft recipients. There were no complications from the infusion(s), no episodes of graft-vs.-host disease (GVHD) and no increase in infections or other complications. There was a trend toward early improved graft survival in marrow recipients. Decreased rejection rates were observed in black recipients.