Increase in the Expression of CD4 + CD25+ Lymphocytic T Cells in the Indeterminate Clinical Form of Human Chagas Disease After Stimulation With Recombinant Antigens of Trypanosoma cruzi.

Purpose: Regulatory T cells are involved in the clinical course of chronic Chagas disease, possibly because they exercise a control in the patient's inflammatory response to Trypanosoma cruzi. This study analyzed the levels of CD4 + CD25+ T cells in chronic Chagas disease patients after in vitro stimulation of the peripheral blood mononuclear cells with CRA (Cytoplasmic Repetitive Antigen) or FRA (Flagellar Repetitive Antigen) T. cruzi antigens. Methods: Groups of patients with the cardiac form and indeterminate form; and non-infected individuals, were selected. The CD4 + CD25+ T lymphocyte population, as well as the FoxP3 expression and the IL10 production, were evaluated by flow cytometry after stimulation with CRA or FRA. Result: The IND group presented higher levels of CD4 + CD25+ T cells than the CARD group. However, there was no evidence of a relationship between FoxP3 and IL10 with any of the chronic forms. Conclusions: Our results suggest the possible involvement of CD4 + CD25+ T cells specific to CRA and FRA in controlling the progression of clinical outcomes. Though, further studies are needed to define which mechanisms activate regulatory T cells and lead to pathology control in chronic human Chagas disease. [ABSTRACT FROM AUTHOR]