Long-term related kidney graft survival in high-risk patients after monitored donor-specific transfusion protocol

Altogether 57 patients were included in the related kidney transplantation program. Forty-four recipients were mixed lymphocyte culture (MLC) negative or slightly positive (SI < 7) against their mother/father donor, and most of them showed Fc gamma RII [erythrocyte antibody inhibition (EAI)] blocking antibody in their sera as the consequence of previous random transfusion. Thirteen patients showed significantly high MLC reactivity against their prospective parent donor (SI > 7) and had no EAI blocking antibody in their sera. The latter group was immunized either by buffy coat or purified platelets obtained from their donor in general two or three times at biweekly intervals. The indication for transplantation of donor-specific transfusion (DST)-treated patients was based on the appearance of EAI antibody and a significant reduction in the MLC reactivity (9 patients). DST patients had 100% kidney graft survival for 5 years and the DST untreated ones 75%. Suggested responsible factors for this observation are the haploidentity in HLA and the induction of suppressive immune regulation by DST.