Additionally, the presence of perforin-expressing CD4+ cytotoxic T-cells has shown an inverse relationship with LVEF (96), while an increase in Foxp3+high CD25+high CD4+ T-cells and IL-17 expression has been associated with a positive LVEF and improved cardiac function in human Chagas disease (97, 98). This evidence concerns the gene FOXP3 and Chagas disease.