HLA-DR1-positive recipients were found to enjoy superior graft survival when compared with DR1-negative patients (72.5% versus 66.5%, p less than 0.00001) in kidneys transplanted since 1980. These patients had the highest graft survival rates in first cadaver, cadaver regraft, and living-related donor transplants. This was seen with patients regardless of the degree of DR-antigen matching. Within one day of the transplant, this advantage of DR1 patients was detectable when graft function was examined. 2. In white recipients, DR1-positive patients had the best graft survival rates. In black recipients, DR1-positive recipients also had the best graft survival rate; however, DR4-positive recipients also had very good graft survival. Whether or not these patients represent a unique population is unclear at this time. 3. In kidneys transplanted since 1983, DR1-positive patients again had the best graft survival rates. This was the case with and without the use of CsA for immunosuppression. DRw9-positive patients had the poorest graft survival rate (52%) in patients without CsA and the best survival rate (84%) of patients treated with CsA; however, because of the low number of patients, these survival rates were not significantly different from the average. 4. In the analysis of transplants performed since 1980, no association between the DRw6 antigen and low graft survival was noted. When the analysis was restricted to grafts transplanted since 1983, DRw6-positive recipients had the poorest graft survival rates. This was true both with and without the use of CsA. No beneficial effect of DRw6 in the kidney donor was seen regardless of the recipient's DR type.
