Lack of alloimmunization to D antigen in D‐negative immunosuppressed liver transplant recipients

BACKGROUND: Orthotopic liver transplantation (OLT) sometimes requires large amounts of blood. An adequate supply of Rh-negative blood for Rh-negative patients is not always available. STUDY DESIGN AND METHODS: Seventeen Rh-negative patients, out of 327 receiving OLT in this hospital, received from 5 to 41 units of Rh-positive red cells during surgery. Each of the 17 patients was followed for 7 weeks to 70 months after OLT for detection of unexpected antibodies. Cyclosporin A and prednisone, azathioprine, and adjunctive rabbit antilymphocyte globulin or monoclonal OKT3 antibody were used to prevent graft rejection. RESULTS: Evidence of immunization, either to D or to antigens in the rest of the red cell antigen systems, did not appear in any patients. CONCLUSION: It is hypothesized that cyclosporin A affects the immune humoral response, inhibiting lymphocyte activation and the primary immune response; consequently, Rh-positive blood may be transfused to Rh-negative OLT recipients so treated with little or no risk of alloimmunization.