FOXP3 and diabetes mellitus: Maintaining immunological homeostasis and preventing autoimmune illnesses requires CD4 Treg %T cells, which are a subset of CD4 T cells that express high levels of the interleukin (IL)-2 receptor α-chain (CD25).28, 29, 30 Williams et al revealed that sustained forkhead box P3 (Foxp3) expression is necessary for mature Treg cells to maintain their suppressor function,31 while mice and humans with a loss-of-function mutation in the Foxp3 gene may suffer from disorders manifested by diabetes and cytokine storms.32