FOXP3 and Autoimmunity: Conventional regulatory T cells (Tregs) are a subpopulation of CD4+ T cells characterized by the expression of the high-affinity IL-2 receptor alpha chain (CD25), transcription factor forkhead box P3 (Foxp3) and low expression of the IL-7 receptor alpha chain (CD127), (CD4+CD25+Foxp3+CD127lo/-) that are essential in regulating other cells in the immune system, to maintain immune homeostasis, prevent autoimmunity and limit chronic inflammatory diseases (1, 2).