Trophoblast cells induce and recruit iTregs by VIP production and through a TGF beta dependent pathway

L. FRACCAROLI; E. GRASSO; V. HAUK; G. MOR; C. PÉREZ LEIRÓS; R. RAMHORST

Milan

Congreso; 15th International Congress of Immunology; 2013

The inducible regulatory T cells (iTreg) population, essential for maternal tolerance of the conceptus, performs its suppressive actions in the critical peri-implantation phase of pregnancy. Vasoactive intestinal peptide (VIP) is synthesized and secreted by trophoblast cells and promotes anti-inflammatory and tolerogenic profiles through binding to specific receptors on immune cells. Here, we evaluated VIP contribution to the differentiation and recruitment of iTreg toward trophoblast cells. We used an in vitro model of maternal leukocyte-trophoblast cell interaction represented by cocultures of fertile women PBMC with human trophoblast cell line (Swan71). We observed that VIP increased the frequency of CD4+CD25+Foxp3+ cells after 48h of coculture (3.9±0.4 vs 8.3%±0.6, p