Choriodecidua and amnion exhibit selective leukocyte chemotaxis during term human labor

ObjectiveThe purpose of this study was to compare the chemotactic activity of the choriodecidua and amnion, and to identify the phenotype of the leukocytes chemoattracted by each tissue.Study DesignAmnion, choriodecidua and whole fetal membranes extracts were obtained from women at term (>37 weeks of gestation) with or without labor (n = 5 each). Extracts were assayed for leukocyte chemotactic activity, and the number and phenotype of the chemoattracted leukocytes were characterized by flow cytometry.ResultsAlthough all of the extracts exhibited chemotactic activity, more leukocytes were chemoattracted by the choriodecidua and the whole fetal membranes during labor compared with no labor (P = .010, .008). During labor the choriodecidua is responsible for granulocyte, T-lymphocyte, monocyte, and natural killer-cell chemoattraction, and the amnion is responsible for B-lymphocyte chemoattraction.ConclusionChoriodecidua and amnion exhibit chemotactic activity for selective leukocytes and thus, each fetal membrane differentially regulates leukocyte chemotactic activity during labor.