CCC patients show an increased number of CD4+ and CD8+ IFN-γ-producing T cells in the peripheral blood, with reduced numbers of IL-10-producing CD4+CD25+ regulatory T cells [15, 35, 36] and CD4+CD25+ FoxP3+ regulatory T cells [37] as compared with patients in the ASY form of Chagas disease. This evidence concerns the gene CD4 and Chagas disease.