In vitro anti-kidney effect of lymphocytes in experimental immunization to placental antigens.

The lymph node and spleen lymphocytes of placenta-sensitized guinea pigs were tested for their ability to destroy kidney monolayer. It was shown by microcytotoxicity assay that these sensitized lymphoid cells killed target monolayer at different effector/target cell ratios. About 35% of kidney cells were destroyed when sensitized lymph node cells were added at a ratio of 500: 1, and 50% at a ratio of 1000:1. Immunized spleen cells produced approximately the same results. No significant cytotoxicity was measured when placenta-sensitized lymphocytes were added to nonrelated mouse skin fibroblasts. In order to exclude the possibility of participation of species-specific antigens in this experimental model, placenta-sensitized lymphocytes were added to L-cell monolayer in the presence of kidney antigens or mouse normal serum (a carrier of species-specific determinants). An extensive cytotoxic effect was observed in the presence of kidney antigens, while addition of mouse normal serum did not induce significant target cell lysis. The cross-reactivity of the cytotoxic ability of placenta-sensitized lymphocytes may indicate that cell-mediated immunity can be involved in the pathogenesis of nephropathy in toxaemic pregnancies, accompanying sensitization by placental antigens.