VIP contributes to the induction and recruitment of iTregs in a TGFbeta dependent pathway

FRACCAROLI L, GRASSO E, HAUK V, MOR G, PÉREZ LEIRÓS C Y RAMHORST R

Iguazú

Simposio; V SLIMP - Latin American Society for Maternal Fetal Interaction & Placenta V LASRI - Latin American Chapter of the American Society of Reproductive Immunology.; 2013

Background Vasoactive intestinal peptide (VIP) is synthesized and secreted by trophoblast cells and induce a tolerogenic profile. We evaluated VIP contribution to the differentiation and recruitment of inducible Treg (iTregs) toward trophoblast cells. Methods Fertile women PBMC and trophoblast cell line (Swan71) were cultured and iTreg frequency and cytokines expression measured by FACS. Suppression assays were determined by thymidine incorporation and migration of differentiated iTreg towards Swan71 cells was performed. Results VIP increased the frequency of CD4+CD25+Foxp3+ cells after cocultures and it was prevented by VIP antagonist. The iTregs suppressed maternal alloresponse. VIP also increased the % of CD4+IL10+ cells but did not modulate IFN or IL-17 production. The increase in iTregs frequency was prevented by an antiTGF neutralizing Ab and VIP antagonist. Finally, Swan71 cells selectively recruited iTregs and this effect was higher in the presence of VIP. Conclusion VIP contributes to the induction and recruitment of iTregs in a TGFbeta dependent mechanism.