Article
Trypanosoma cruzi Experimental Infection Impacts on the Thymic Regulatory T Cell Compartment
Registro en:
GONZÁLEZ, Florencia Belén; et al. Trypanosoma cruzi Experimental Infection Impacts on the Thymic Regulatory T Cell Compartment. PLoS Negl Trop Dis., v.10, n.1, e0004285, 21p, Jan. 2016.
1935-2727
10.1371/journal.pntd.0004285
1935-2735
Autor
González, Florencia Belén
Calmon-Hamaty, Flavia
Cordeiro, Synara Nô Seara
Bussy, Rodrigo Fernández
Spinelli, Silvana Virginia
D`Attilio, Luciano
Bottasso, Oscar
Savino, Wilson
Almeida, Vinícius Cotta de
Villar, Silvina Raquel
Pérez, Ana Rosa
Resumen
The dynamics of regulatory T cells in the course of Trypanosoma cruzi infection is still
debated. We previously demonstrated that acute murine T. cruzi infection results in an
impaired peripheral CD4+Foxp3+ T cell differentiation due to the acquisition of an abnormal
Th1-like phenotype and altered functional features, negatively impacting on the course of
infection. Moreover, T. cruzi infection induces an intense thymic atrophy. As known, the thymus
is the primary lymphoid organ in which thymic-derived regulatory T cells, known as
tTregs, differentiate. Considering the lack of available data about the effect of T. cruzi infection
upon tTregs, we examined tTreg dynamics during the course of disease. We confirmed
that T. cruzi infection induces a marked loss of tTreg cell number associated to cell precursor
exhaustion, partially avoided by glucocorticoid ablation- and IL-2 survival factor depletion.
At the same time, tTregs accumulate within the CD4 single-positive compartment,
exhibiting an increased Ki-67/Annexin V ratio compared to controls. Moreover, tTregs
enhance after the infection the expression of signature markers (CD25, CD62L and GITR)
and they also display alterations in the expression of migration-associated molecules (α
chains of VLAs and chemokine receptors) such as functional fibronectin-driven migratory
disturbance. Taken together, we provide data demonstrating profound alterations in tTreg
compartment during acute murine T. cruzi infection, denoting that their homeostasis is significantly
affected. The evident loss of tTreg cell number may compromise the composition
of tTreg peripheral pool, and such sustained alteration over time may be partially related to
the immune dysregulation observed in the chronic phase of the disease.