T cell activation in abnormal perinatal events

Abstract

The aim of this study was to determine the percentage of CD45RO+ T cells in umbilical cord blood from neonates born at less than 37 weeks of gestation. Fifty-nine patients were enrolled in this study, including49withpretermand10withtermdeliveries. Pretermdeliveriesweredividedintotwocategories; spontaneous (Group A, n = 31) and indicated (Group B, n = 18). Perinatal infection was categorized as C-CAM, H-CAM and neonatal infection. The percentage of CD45RO+ T cells in the umbilical cord was assessed using flow cytometry. IL-6 was measured using ELISA. In Group A, the percentage of CD45RO+ T cells and concentrations of IL-6 in patients with perinatal infection (n = 18) were significantly higher than in those without perinatal infection (n = 13). A significant correlation between percentage of CD45RO+ T cells and IL-6 concentrations was observed in the cord blood (r =0.62, P =0.001). InGroup B, pink-tinged amniotic fluid was observed in seven cases. In these cases, an increase in the percentage of CD45RO+ T cells (>10%) was noted. In the cases without perinatal infection, which included all those delivered at term(n =32), no correlation was observed between the percentage of CD45RO + T cells and gestational age atdelivery (r=-0.139,P=0.448).We concluded that a highpercentage ofCD45RO+ cord blood T cells is observed not only in perinatal infection, but also in the presence of abnormal perinatal events such as maternal bleeding in pretermgestation. © 2009 The Societies and Blackwell Publishing Asia Pty Ltd.