Cellular immunity in normal pregnancy and abortion: subpopulations of T lymphocytes bearing Fc receptors for IgG and IgM.

Studies on the change of peripheral T and B lymphocytes and T cells bearing Fc receptors for IgG (IgG.FcR+.T lymphocytes) and IgM (IgM.FcR+.T lymphocytes) in normal pregnant women and patients with threatened abortion were performed by using rosette-formation tests. There was no significant difference in the proportion of T and B lymphocytes between pregnant and nonpregnant women. The percentage change of T cells of the patients in threatened abortion with good prognosis was significantly decreased and that of B cells of the patients in threatened abortion was significantly increased compared with that of normal pregnant women. The percentage of IgG.FcR+.T lymphocytes in the T lymphocytes increased in the various stages of pregnant and postpartum women as compared with that in nonpregnant women, and in the case of the patients with threatened abortion it also increased significantly from that of normal pregnant women. On the contrary, the percentage of IgM.FcR+.T in the T lymphocytes decreased in normal pregnant and postpartum women.