Simultaneous Administration of Adjuvant Donor Bone Marrow in Pancreas Transplant Recipients.

Abstract

91 Purpose: The effect of donor bone marrow was evaluated for its potential favorable effect in our simultaneous pancreas/kidney (SPK) transplant program over a 4 year period. Methods: From July 1994 through August 1998, 164 pancreas transplants were performed, 140 of which were SPK. All patients received tacrolimus, mycophenolate mofetil and steroids for immunosuppression (azathioprine was used in the first year of the program). Fifty-three SPK patients received perioperative unmodified donor bone marrow (BM), 3-6 × 106 cells per kg. Results: Overall actuarial survival at 1 and 3 years was 98% and 97% (patient), 96% and 89% (kidney) and 86% and 82% (pancreas), respectively. In the adjuvant donor bone marrow group 1 and 3 year survival was 96% and 93% (patient) and 83% and 83% (pancreas), respectively. Three deaths were unrelated to BM and occurred 6 months to 3 years in patients with early graft losses. For 87 non-BM recipients, survival at 1 and 3 years was 100% and 100% (patient) and 88% and 80% (pancreas), respectively. No pancreas grafts were lost after 3 months in the BM recipients, and 3 in the non-BM recipients were lost to rejection at 10, 22 and 26 months, respectively. Fifty-seven percent of BM patients were off steroids at one year, 65% at 2 years and 83% at 3 years, respectively: 52% of the non-BM patients were steroid-free at one year, 53% at 2 years and 62% (p< 0.007) at 3 years, respectively. The mean acute cellular rejection rate was 67% in the BM group and 83% in the non-BM patients (includes borderline rejection and multiple rejections). The level of donor cell chimerism in the peripheral blood of BM patients was at least two log higher than in the controls. Conclusion: In this series, which represents the largest experience with adjuvant BM infusion in pancreas recipients, there was a higher steroid withdrawal rate (p< 0.007), fewer rejection episodes, and no pancreas graft loss after 3 months in BM recipients compared to contemporaneous controls. Donor bone marrow administered perioperatively may have a protective effect in pancreas transplantation.