Trophoblast cells condition neutrophil activation to maintain immune homeostasis at early pregnancy

CALO, GUILLERMINA; SABBIONE, FLORENCIA; PAPARINI, DANIEL; RAMHORST, ROSANNA; TREVANI, ANALIA; PÉREZ LEIRÓS, CLAUDIA

Mar del Plata

Simposio; VI SLIMP V LASRI; 2015

Latin American Society for Maternal Fetal Interaction and Placenta

PA-27 Homeostasis maintenance at the maternal-placental interface is a dynamic process that involves different populations of leukocytes controlled by trophoblast cells favoring a tolerogenic microenvironment. In preeclampsia, neutrophil activation is increased compared with normal pregnancies. Vasoactive intestinal peptide (VIP) is produced by trophoblast cells and proposed to contribute to immune homeostasis at early pregnancy. Objective: To explore the profile acquired by human neutrophils after interaction with trophoblast cells with special focus on VIP effect. Methods: Blood was obtained from healthy donors, neutrophils were purified on Ficoll-Triyosom gradient and Dextran sedimentation, and cultured with conditioned media from first trimester human cytotrophoblast cells Swan-71 (CM) or VIP. Neutrophils were stimulated with fMLP or PMA; CD11b expression and ROS production were evaluated by cytometry; DNA and elastase activity by fluorometry and spectrophotometry. Migration through transwells was quantified by cytometry. Spontaneous apoptosis was assessed by fluorescence microscopy and phagocytosis of apoptotic cells by macrophages by cytometry. Results: Neutrophil interaction with CM or VIP modulated their functional profile, according to activation markers, migration capacity and spontaneous apoptosis. Both CM and VIP diminished CD11b expression and ROS production upon fMLP stimulation (ROS-MIF X±SE: fMLP: 1076±163; fMLP+VIP10nM: 644±91; fMLP+CM: 777±107; P