Kinetics of mixed lymphocyte reaction after blood transfusions

The kinetics of mixed lymphocyte reaction (MLR) was studied in an unrelated pair of potential kidney graft donor and recipient. The recipient immunological reactivity to donor cells was specifically modulated by donor blood transfusions. Prior to transfusions, recipient MLR to donor lymphocytes expressed as per cent of the relative response (% RR) was 85.73. It dropped to 43.75 on the 21st posttransfusion day, and was as low as 19.16 on the 151st day (5th month). Next, a gradual increase in MLR occurred. The % RR increased to 46.15 in the 9th month and returned close to the pretransfusion level, to 78.30, in the 12th month. Transplantation of the kidney from the potential donor was not performed.