Influence of maternal killer-cell immunoglobulin-like receptors and parental HLA-C genotypes on predisposition to recurrent miscarriage

Killer-cell Immunoglobulin-like receptors (KIR) expressed by natural killer (NK) cells at the site of placentation, can bind to human leukocyte antigen (HLA-C) molecules on trophoblast cells. Both systems are genetically highly polymorphic, in which their interactions result in release of varieties of cytokines and chemokines. The factors modulate placental relationship between mother and her fetus. Thus, it has been hypothesized that each of the particular maternal KIR/fetal HLA-C genotype combinations have different effect in pregnancy success. The patients were 92 couples and 8 women with three or more recurrent miscarriage (RM) with no physiologic or pathologic reason for their problem. Also, 100 healthy porous women were selected as control group. DNA were isolated from the whole blood specimens and genotyped for HLA-C groups and 5 KIR genes (KIR2DS1, KIR2DS2, KIR2DL1, KIR2DL2, KIR2DL3) using PCR-sequences-specific primer method (SSP). Statistical analysis shown, that frequency of the HLA-C2 group is raised in the affected female compared with porous women. The frequencies of activating KIRs in the male of partner of RM were similar to controls women while it had been decreased in the affected female compared with porous women although these don’t reach significant. Our findings support the idea that interaction between maternal KIR on NK cells and paternal HLA-C expressed trophoblast cells, affect the successful placentation.