Natural killer cell activity and antibody dependent cell-mediated cytotoxicity in preeclampsia

Natural killer cell activity and antibody dependent cell-mediated cytotoxicity (NK and ADCC) of peripheral blood lymphocytes were measured against K-562 and antibody coated HSB target cells with a 4-h chromium release assay in 19 primigravidas with preeclampsia. Nineteen primigravidas with an uncomplicated pregnancy and 19 nonpregnant women served as controls. Lymphocyte NK and ADCC activities are significantly lower in primigravidas than in nonpregnant women. Primigravidas with preeclampsia have similar cell-mediated cytotoxic activities to primigravidas with an uncomplicated pregnancy. These findings support the hypothesis that maternal acceptance of the fetal-allograft is due to suppression of cell-mediated cytotoxicity. Altered cellular cytotoxicity appears unlikely as a cause of preeclampsia. Our results, however, do not preclude local changes in cellular immune activities that may occur at the implantation site.