[Placental proteins as regulators of immunological reactions in pregnancy].

The effect of two specific placental proteins, trophoblastic beta 1-glycoprotein (TBG) and chorionic alpha 1-microglobulin (CAG), on the immunological reactions was studied in vitro. TBG in physiological doses suppressed the proliferation of lymphocytes induced by plant mitogens and allogenic cells in the unidirectional mixed cultures, strengthened the effect of concanavalin A upon the induction of cells-suppressors in the culture and, in low concentrations, decreased the percentage of E- and EAC-rosette-forming cells. In none of the tests used CAG was effective. But when studying the effect of TBG and CAG mixture on PHA-induced proliferation of lymphocytes the inhibiting effect of TBG was weakened and, in some cases, completely relieved.