Kidney transplantation in rhesus monkeys. Matching for D/DR antigens, pretransplant blood transfusions, and immunological monitoring before transplantation.

The effect of matching for D/DR antigens and of three pretransplant blood transfusions on kidney allograft survival was investigated in unrelated rhesus monkeys treated with standard immunosuppression. A control group consisting of host-donor combinations mismatched for one or two DR antigens (mixed lymphocyte culture (MLC) positive) and not receiving transfusions showed a MST of 13 +/- 1.2 days with a range from 9 to 22 days. The administration of pretransplant blood transfusions led to a MST of 28 +/- 5.4 days with 5 of 12 animals showing survival times of more than 22 days (i.e., a bimodal distribution of survival times). Recipients matched with their donors for two DR antigens and given transfusions showed an even better MST of 39 +/- 4.0 days. Under these conditions, MLC-negative combinations fared slightly better than MLC-positive ones: only 1 of 10 animals showed a survival time of less than 22 days and kidney function in the first weeks after transplantation was significantly better. When mixed lymphocyte reactions (MLC reactivity) between host and donor before and after the transfusions were compared, it was possible to predict to some extent the eventual fate of an allograft: increased mixed lymphocyte reaction predicted relatively short survival times, decreased mixed lymphocyte reaction relatively long ones (P less than 0.01).