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

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

Congreso; V SLIMP - IV LASRI Meeting 2013; 2013

Background: Vasoactive intestinal peptide (VIP) is synthesized and secreted by trophoblast cells and induce a tolerogenic prole. We evalu- ated VIP contribution to the differentiation and recruitment of inducible Treg (iTregs) toward trophoblast cells. Methods: Fertile women PBMC and trophoblast cell line (Swan71) were co-cultured and iTreg frequency and cytokines expression measured by FACS. Suppression assays were determined by thymidine incorporation and migration of differentiated iTreg towards Swan71 cellswas performed. Results: VIP increased the frequency of CD4þCD25þFoxp3þ cells after cocultures and it was prevented by VIP antagonist. The iTregs suppressed maternal alloresponse. VIP also increased the % of CD4þIL10þ cells but did not modulate IFNg or IL-17 production. The increase in iTregs frequency was prevented by an antiTGFb 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.