Blood transfusion suppresses cutaneous cell-mediated immunity.

Cutaneous cell-mediated immunity (CMI) evoked by dinitrochlorobenzene (DNCB) was evaluated in end-stage renal disease patients on regular haemodialysis and before renal transplantation. Twenty-seven per cent of the patients had suppression of cutaneous CMI as shown by a negative response upon DNCB challenge. We analysed seven factors known or postulated to have an influence on renal allograft rejection for their effects on cutaneous CMI. Age, sex, red blood cell groups, pathogenesis of the underlying kidney disease, and HLA-DRw6 status had no direct effect on the DNCB response. The number of blood transfusions and the duration of haemodialysis were related to a decrease of the DNCB response but were at the same time correlated. By multiple regression analysis it was shown that the number of blood transfusions had a major suppressive effect on the DNCB response, whereas the duration of haemodialysis had a minor suppressive effect if any. Thus the cutaneous CMI evoked by DNCB partly reflects a general CMI response involved in allograft rejection as well. At the same time the effect of blood transfusion on cutaneous CMI restricts the application of the DNCB test for prediction of future renal allograft rejection.