Effects of histocompatibility testing versus immunoreactive predisposition on kidney transplant survival

From January 1979 to August 1981, 76 primary renal transplants were performed at the University of Miami-Jackson Memorial Hospital. Fifty-five of these were from living, related (LR) donors and 21 were from cadaver (CAD) donors. Histocompatibility typing for HLA-A, -B, and -DR antigens and of mixed lymphocyte culture (MLC) were performed. In LR patients the ability to generate donor-specific and nonspecific suppressor cells in vitro was tested preoperatively. Serial posttransplant immunologic monitoring was used in all patients by determining total T-cell numbers (E rosette-forming cells) as well as helper and suppressor T-cell subsets by use of monoclonal antibodies. Overall patient and graft survival was 90% and 87%, respectively. In this study MLC reactivity did not correlate with DR typing in CAD recipients, most of whom had marked reaction despite one or two DR antigen matches. Graft survival was also independent of MLC reactivity in both LR and CAD patients. The ability of LR recipients to generate donor-specific suppressor cells in vitro before transplantation did correlate significantly with absence of rejection episodes. Immunologic monitoring with T-cell subsets had prognostic significance for the detection of patients with excessive immunosuppression and high risk for development of infection (P less than 0.001). Thus, the responder status of many transplant recipients seemed as important as the current assessment of histocompatibility in influencing graft survival.