Influence of sex on histocompatibility matching in renal transplantation.

Histocompatibility matching for the HLA-A and HLA-B loci specificities influenced the survival of cadaver kidney transplants in male recipients but not in female recipients. The correlation between HLA matching and transplant survival for a three-year follow-up period was highly significant for 3455 male recipients but not significant for 2007 female recipients. Since this effect was not dependent on the sex of the donor, a sex-associated histocompatibility antigen could not have been responsible. The reason why histocompatibility matching influences one sex and not the other is not known. The observation may have improtant practical consequences and may help to explain difficulties in establishing a strong correlation between HLA matching and cadaver transplant outcome.