Blood transfusion-induced facilitation of kidney graft survival in rats (congenic-resistant strains).

The correlation between the degree of histoincompatibility and kidney graft survival after active sensitization by blood transfusions has been investigated in congenic resistant strains of rats with MHC (H-1)-restricted incompatibility as compared to standard strains. It has been found that the beneficial effect of transfusions for graft survival becomes most evident when compatibility for the so-called minor non-H-1-antigens exists. H-1-congenic rats with MHC differences alone show indefinite graft survival irrespective of the interallelic combination. Donor-specific sensitization is the treatment of choice. Third-party blood is by far inferior. H-1-identical, but non-H-1-different blood, with respect to the recipient strain genotype, is ineffective in the facilitation of H-1-different grafts. The facilitation effect does not increase with the number of blood injections. As early as 1 week after blood treatment, there is permanent survival of grafted kidneys, but there is a definite loss of graft-protecting factors with time.