Blood transfusions as pretreatment for kidney transplantation: immunization rate and effect on cellular immune response in vitro.

A group of 28 untransfused uremic patients was given five or more units of stored blood as pretreatment for kidney transplantation; 9 patients formed lymphocytotoxic antibodies against B cells and 1 patient developed multispecific antibodies against both B and T cell panels (greater than 80% reactivity). During the same period 22 previously transfused patients received up to five transfusions as pretreatment for kidney transplantation. B cell antibodies were formed by 10 patients, and 4 of these patients also formed T cell antibodies, 2 with broad reactivity. Cellular immune reactivity in vitro was studied on frozen cells from 17 randomly chosen patients. After five blood transfusions no significant changes were seen in blood lymphocyte responses to phytohemagglutinin (PHA), Concanavalin A (Con A), or in mixed lymphocyte cultures (MLC) and cell-mediated lympholysis (CML). After transfusion 3 patients got Non-A, non-B hepatitis and were withdrawn for up to six months from the transplantation list because of increased S-ALAT and S-ASAT. Of the 50 patients, 27 have received kidney grafts, 6 out of 20 who were sensitized, and 21 out of 30 who were nonsensitized. Because of positive crossmatches no patient with multispecific T cell antibodies has received a graft. We conclude that our transfusion regimen for kidney recipients has rendered barely one-third of the patients sensitized (mostly against B cells) and 3 out of 50 hypersensitized. No effect on T cell reactivity could be seen following five planned transfusions. Because fewer patients with antibodies received grafts (30% with antibodies, as compared with 70% without [P less than 0.01]) the blood transfusions seem to have led to a selection effect.