Donorspecific transfusion (DST) and long term related kidney graft survival in high risk patients

The beneficial effect of transfusion is debated in the last decade when cyclosporine and other sophisticated immunosuppressive regimens were introduced in the clinical practice of kidney transplantation. We would like to show that in certain cases this immunoregulatory mechanism should be taken into consideration. Altogether 64 patients were included in the related kidney transplantation program in the last ten years. In all cases transplantation was performed with the HLA haploidentical parental donor. Forty-four recipients were MLC negative or slightly positive (SI<7) against their mother/father donor, and most of them showed Fcγ RII (EAI) blocking antibodies in their sera in the consequence of previous random transfusion. Thirteen patients represented significantly high MLC reactivity against their prospective parental donor (SI>7) and had no EAI blocking antibodies in their sera. The latter group was immunised being generally transfused either with buffy coat or purified platelets from their donor (DST) 2-3 times at biweekly intervals. The indication for transplantation of DST treated patients was based on the appearance of EAI antibodies and significant reduction of the MLC reactivity. Nine of 13 patients were transplanted. The residual 4 patients were not transplanted because EAI antibody production could not be induced. DST patients had 100% kidney survival for 3, and 62% for 9 years. The suggested mechanism induced by the special DST protocol is discussed on the basis of previous published data (Clin Transpl 1996, 10:455, Eur J Immunogen 1995, 32:147). Thus, in case of haploidentity in HLA and mismatching in non-MHC alloantigenes between related donor and recipient, DST may induce cell-mediated suppressive regulation followed by "blocking" alloantibody production with Fcγ RII and MLC function suppressive properties, resulting in prolonged graft survival.