Increased HLA-DR homozygosity associated with pre-eclampsia

It is generally accepted that maternal recognition of paternally derived fe tal antigens occurs during normal pregnancy and may be beneficial for impla ntation and maintenance of gestation, Thus, we have investigated the human leukocyte class II DR antigens (HLA-DR), whose role in self and non-self re cognition is well known, in women with preeclampsia, their partners and in control couples. The HLA-DR antigens were tested in 70 pre-eclamptic primig ravidae women and their partners and 70 healthy control couples using the s erological Terasaki technique, Our results did not show any particular HLA- DR antigen to be correlated with pre-eclampsia, but a statistically signifi cant increase of only one identifiable HLA-DR antigen, which was presumed t o express homozygosity at the HLA-DR locus, in the pre-eclamptic women and their partners: 67.1 versus 7.9% in the control couples (P < 0.000001). The analysis of HLA-DR compatibility between pre-eclamptic women and their par tners showed a statistically highly significant increase of the female-to-m ale compatibility (P = 0.0003) and a lower but significant male-to-female c ompatibility in comparison with controls (P = 0.014). From our results, it emerges that HLA-DR homozygosity and reduced antigenic disparity seem to be associated to a major risk for pre-eclampsia, which consequently appears t o be a 'couple's disease'.