SUMMARYWe calculated the percentage of Th1, Th2, Th0 cells and the Th1:Th2 cell ratio of peripheral blood from normal pregnant subjects and preeclampsia patients using¯ow cytometry which can analyse both the surface marker, CD4, and intracellular cytokines, interleukin (IL)-4 and interferon (IFN)-g. In normal pregnancy, the percentage of Th1 cells was signi®cantly lower in the third trimester, and the ratios of Th1:Th2 were signi®cantly lower in the second and third trimester than in nonpregnant subjects. In contrast, the percentage of Th1 cells and the ratios of Th1:Th2 in preeclampsia were signi®cantly higher than in normal third trimester pregnant subjects. The percentage of Th2 cells in preeclampsia was signi®cantly lower than in third trimester of normal pregnancy. Additionally, peripheral blood mononuclear cells from these subjects and patients were cultured with phytohemagglutinin stimulation, and IL-4 and IFN-g concentrations were determined in the supernatant by enzymed linked immunosorbent assays. The percentage of Th1 and Th2, and the ratios of Th1:Th2 were correlated with cytokine (IFN-g and IL-4) secretion level. These results demonstrated that Th2 cells were predominant in the second and third trimesters of normal pregnancy, but Th1 cells predominated in preeclamptic patients.

No abstract

Summary CD4+ CD25 bright regulatory T (Treg) cells have been identified as a principle regulator of tolerance during pregnancy. In the setting of pre-eclampsia, however, little is known about the dynamics of these cells. In the current study, we determined CD4 + CD25 bright Treg cells in the peripheral blood using flow cytometry and forkhead box P3 (FoxP3 + ) cells at the placental bed using immunohistochemical staining. Peripheral blood mononuclear cells (PBMC) of 38 pre-eclamptic cases (17 cases Japanese, 21 cases Polish), 40 normal late pregnancy subjects (20 subjects Japanese, 20 subjects Polish), and 21 non-pregnant healthy controls (10 subjects Japanese, 11 subjects Polish) were included. We found the percentage of CD25 bright cells within the CD4+ T cell population in PBMC was reduced significantly in both Japanese and Polish pre-eclamptic cases than in normal pregnancy subjects (P < 0·001) and non-pregnant healthy controls (P < 0·001). Also, the percentage of FoxP3+ cells within CD3 + T cells in the placental bed biopsy samples of pre-eclamptic cases were decreased compared to those in normal pregnancy subjects. These findings suggest that a decreased number of Treg cells was present in pre-eclampsia, and these changes might break the maternal tolerance to the fetus.

No abstract

Up-regulation of Th1 responses and down-regulation of Th2 responses occur in preeclampsia.