FOXP3 and immune dysregulation-polyendocrinopathy-enteropathy-X-linked syndrome: Foxp3 plays an essential role in the suppressive functions of Tregs [5], and Foxp3 deficiency causes multiorgan autoimmune diseases such as those observed in the scurfy mouse and in patients with immunodysregulation polyendocrinopathy enteropathy X-linked syndrome (IPEX) [6, 7].