Distribution of Th1, Th2, and Th0 and the Th1/Th2 cell ratios in human peripheral and endometrial T cells

PROBLEM: To examine whether normal pregnancy involves type 2 T-helper (Th2) immune condition or not. METHOD OF STUDY: We measured the percentage of Th0, Th1, and Th2 and the Th 1/Th2 cell ratios of human peripheral blood and endometrial T cells using f low cytometry, which can analyze both the surface marker CD3, and intracell ular cytokines, interleukin 4 (IL-4) and interferon gamma (IFN gamma). RESULTS: No significant differences were found in the percentages of Th1, T h2, and Th0 and the Th1/Th2 cell ratios in the peripheral blood T cells of nonpregnant women and women in early pregnancy. On the other hand, the perc entage of Th1 cells was highest during the proliferative phase of the endom etrium, followed by the secretory phase and early pregnancy decidua. The pe rcentage of Th2 cells was highest in early pregnancy decidua and lowest dur ing the proliferative phase of the endometrium. The Th1/Th2 ratio was 147.4 8 +/- 96.68 during the proliferative phase of the endometrium, 37.74 +/- 21 .33 during the secretory phase, and 1.31 +/- 0.48 in the early pregnancy de cidua. CONCLUSIONS. These data indicate that Th1 cells predominate in the nonpregn ant endometrium, especially during the proliferative phase, while Th2 cells predominate in early pregnancy decidua.