Congenital infection with Trypanosoma cruzi primes cord blood Vd2 T cells to proliferate in response to isopentenyl pyrophosphate.

Abstract

Event Abstract Back to Event Congenital infection with Trypanosoma cruzi primes cord blood Vδ2 T cells to proliferate in response to isopentenyl pyrophosphate. Cristina Alonso-Vega1*, Emmanuel Hermann2, Carine Truyens3, Aurélie Berthe3, Amilcar Flores1, Rudy Parrado1, Faustino Torrico1 and Yves Carlier3 1 Universidad Mayor de San Simón, IIBISMED, Facultad de Medicina, Bolivia 2 CIIL - Center for Infection and Immunity of Lille, Institut Pasteur de Lille, Team 10: Basic and Clinical Immunology of Parasitic Diseases, France 3 Faculté de Médecine, Université Libre de Bruxelles (U.L.B.), Laboratoire de Parasitologie, Belgium Trypanosoma cruzi is the protozoa agent of Chagas’ disease in South America. Our team has previously demonstrated that newborns congenitally-infected with T. cruzi develop a parasite-specific CD8 αβ T cell immune response in utero. In the present study, we have investigated whether cord blood TCRVδ2 T cells were also involved in such response, by analysing their phenotype and their capacity to proliferate in response to isopentenyl pyrophosphate (IPP) in both uninfected and congenitally-infected newborns. We found that Vδ2 T cells can be expanded following congenital infection with T. cruzi. Cord blood Vδ2 T cells from congenitally-infected newborns expressed inhibitory NK cell receptors such as NKG2A and killer inhibitory receptors. Moreover, they vigorously expand in response to IPP combined with IL-2. Altogether these results demonstrate that Vδ2 T cells can be activated in utero and that these cells can be primed to respond to phosphoantigens. In conclusion, this work demonstrates that congenital infection with T. cruzi induces significant activation of fetal γδ T cells in utero, and supports the notion that it’s possible to boost the γδ T cell immune response in early life. Acknowledgements We thank Eduardo Suarez and the staff of the maternity German Urquidi (Cochabamba, Bolivia) for the management of patients, Mary-Cruz Torrico, Miguel Guzman and Marco Antonio Solano (CUMETROP/LABIMED, U.M.S.S., Cochabamba, Bolivia) for performing the serological and parasitological diagnosis of patients.