Rat pregnancy immunoregulatory circuits are progestation hormonal status, decidual tissue, embryo-trophoblast and late pregnancy changes dependent.

We have tested the spleen cells of rats for their reactivity to mating and unrelated (third party) strain alloantigens during pregnancy, pseudopregnancy, and traumatic deciduoma installation. By cytotoxic T-lymphocyte assays, after 7-day one-way mixed lymphocyte cultures (MLC), we detected the presence of many immunoregulatory circuits among rat pregnancy and postpartum. They are progestation hormonal status, decidual tissue, embryo-trophoblast, late-pregnancy-parturition-associated changes, and lactation-hormonal-status dependent.