Lymphocyte transformation during pregnancy: an analysis using whole-blood culture.

In an effort to provide information on maternal immunocompetence, a study was undertaken to measure lectin-induced transformation of maternal lymphocytes. Whole-blood culture was used. The phytohemagglutinin (PHA)-induced lymphocyte transformation of 137 pregnant women was significantly (P less than 0.05 to 0.001) diminished until 21 weeks' gestation, and concanavalin A (Con A)-induced lymphocyte transformation of 116 pregnant women was also significantly (P less than 0.01 to 0.001) diminished at all stages of gestation, as compared with those of 39 nonpregnant women. In addition, the Con A-induced lymphocyte transformation of ovarian venous blood and uterine venous blood from a pregnant woman was prominently diminished, as compared with that of basilic venous blood. It is suggested that there are maternal T-cell subpopulations that have different reactivities to PHA and Con A.