Proportional changes of CD4+ CD2 5 + Foxp3 + Regulatory T cells in mate rnal peripheral blood during pregnancy and labor at term and preterm

Abstract

Purpose: To evaluate the proportional changes of CD4C+D25Foxp3+ regulatory T cells (Tregs) in maternal peripheral blood during pregnancy and labor at term and preterm. Methods: Peripheral blood was collected from 20 non-pregnant controls and 139 pregnant women (60 at different gestational ages, 48 at term with or without labor, and 31 in threatened or actual preterm labor). CD4+CD25+Foxp+ Tregs in peripheral blood samples were analyzed in peripheral blood samples b) How cytometry. Placentas from preterm women were examined for the presence of histological chorioamnionitis (HC). Results: The percentage of circulating CD4+CD25+Foxp3+ Tregs was significantly increased in women during the first trimester compared with non-pregnant controls (P<0.0001), peaking during the second trimester and then declining slightly in the third trimester. There was a significantly lower level of CD4+CD25+Foxp3+ Tregs in women with term labor than in those at term without labor (P<0.0001). Women admitted in preterm labor had a lower proportion of CD4CD25+Foxp3 cells than those admitted with threatening preterm labor (P<0.0001). Preterm women with evidence of HG had decreased proportion of CD4+CD25+Foxp3+ cells than those without HC in preterm deliveries (P=0.008). Moreover, the percentages of CD4+CD25+Foxp+ cells in preterm subjects, irrespective of the HC status, were significantly diminished compared with women with normal pregnancy at the same gestational age (P<0.0001). Conclusion: Our data reveal a marked elevation of peripheral blood CD4+CD25+Foxp3+ Tregs during early pregnancy, but a dramatic decline during labor, either at term or preterm, suggesting their involvement in the maintenance of pregnancy and the initiation of labor.© 2010 CIM.