Limited Foxp3+ Regulatory T Cells Response During Acute Trypanosoma cruzi Infection Is Required to Allow the Emergence of Robust Parasite-Specific CD8+ T Cell Immunity

Bibliographic Details
Title: Limited Foxp3+ Regulatory T Cells Response During Acute Trypanosoma cruzi Infection Is Required to Allow the Emergence of Robust Parasite-Specific CD8+ T Cell Immunity
Authors: Cintia L. Araujo Furlan, Jimena Tosello Boari, Constanza Rodriguez, Fernando P. Canale, Facundo Fiocca Vernengo, Santiago Boccardo, Cristian G. Beccaria, Véronique Adoue, Olivier Joffre, Adriana Gruppi, Carolina L. Montes, Eva V. Acosta Rodriguez
Source: Frontiers in Immunology, Vol 9 (2018)
Publisher Information: Frontiers Media S.A., 2018.
Publication Year: 2018
Collection: LCC:Immunologic diseases. Allergy
Subject Terms: regulatory T (Treg) cells, Trypanosoma cruzi, immunity, CD8 cytotoxic T cells+, pathogenesis, Immunologic diseases. Allergy, RC581-607
More Details: While it is now acknowledged that CD4+ T cells expressing CD25 and Foxp3 (Treg cells) regulate immune responses and, consequently, influence the pathogenesis of infectious diseases, the regulatory response mediated by Treg cells upon infection by Trypanosoma cruzi was still poorly characterized. In order to understand the role of Treg cells during infection by this protozoan parasite, we determined in time and space the magnitude of the regulatory response and the phenotypic, functional and transcriptional features of the Treg cell population in infected mice. Contrary to the accumulation of Treg cells reported in most chronic infections in mice and humans, experimental T. cruzi infection was characterized by sustained numbers but decreased relative frequency of Treg cells. The reduction in Treg cell frequency resulted from a massive accumulation of effector immune cells, and inversely correlated with the magnitude of the effector immune response as well as with emergence of acute immunopathology. In order to understand the causes underlying the marked reduction in Treg cell frequency, we evaluated the dynamics of the Treg cell population and found a low proliferation rate and limited accrual of peripheral Treg cells during infection. We also observed that Treg cells became activated and acquired a phenotypic and transcriptional profile consistent with suppression of type 1 inflammatory responses. To assess the biological relevance of the relative reduction in Treg cells frequency observed during T. cruzi infection, we transferred in vitro differentiated Treg cells at early moments, when the deregulation of the ratio between regulatory and conventional T cells becomes significant. Intravenous injection of Treg cells dampened parasite-specific CD8+ T cell immunity and affected parasite control in blood and tissues. Altogether, our results show that limited Treg cell response during the acute phase of T. cruzi infection enables the emergence of protective anti-parasite CD8+ T cell immunity and critically influences host resistance.
Document Type: article
File Description: electronic resource
Language: English
ISSN: 1664-3224
Relation: https://www.frontiersin.org/article/10.3389/fimmu.2018.02555/full; https://doaj.org/toc/1664-3224
DOI: 10.3389/fimmu.2018.02555
Access URL: https://doaj.org/article/89675fb7b2c64350af68960726eb620a
Accession Number: edsdoj.89675fb7b2c64350af68960726eb620a
Database: Directory of Open Access Journals
More Details
ISSN:16643224
DOI:10.3389/fimmu.2018.02555
Published in:Frontiers in Immunology
Language:English