HLA-DR matched transfusions - Development of donor-specific T- and B-cell antibodies and renal allograft outcome

Background, Pretransplant blood transfusions are reported to decrease acute rejection rate and increase graft survival after renal transplantation. Th is has been attributed to matching for HLA-DR with the transfusion donor, w hich also results in a lower rate of sensitization. Methods. The development of donor-specific T- and B-cell antibodies was mea sured by National Institutes of Health and two-color fluorescence assays af ter one transfusion in 247 naive patients. Auto-cross-matches were performe d to exclude autoantibodies, Patients were grouped according to DR-matching (n=107) or nonmatching (n=140) with the transfusion donor. In 103 renal al lograft recipients, acute rejection rate and graft survival were analyzed b y Cox regression. Results. T-cell antibodies developed in 6.5% of the patients. There was no difference between the DR-matched and nonmatched group. No auto-antibodies against T-cells developed, whereas one quarter of the sera had a positive B -cell auto-cross-match. There was no difference with regard to B-cell antib odies (autoantibody-positive sera excluded) between the DR-matched (15.8%) and nonmatched (18.6%) group. Sharing of HLA A and/or B antigens did not re sult in a lower frequency of donor-directed T- or B-cell antibodies. None o f the risk factors, including DR sharing with transfusion donor, contribute d significantly towards graft survival (odds ratio for DR sharing: 1.02; 95 % confidence interval: 0.45-2.32; P=0.97), DR sharing was no risk factor to wards acute rejection either, in contrast to DR mismatch with kidney donor (odds ratio: 2.9), and use of cyclosporine versus tacrolimus (odds ratio: 4 .4). Conclusions. Development of donor-directed T-cell antibodies after one tran sfusion of leukocyte-poor blood is low and irrespective of HLA-DR match wit h transfusion donor. B-cell antibodies develop more frequently and independ ent of HLA-DR match. In 26% of the sera, B-cell auto-antibodies are detecte d. Rejection rate and graft survival are not significantly different betwee n HLA-DR-matched and nonmatched transfusions.