IL2 and Autoimmunity: The lack of autoimmunity in Cd25Y129H mice could also be explained by an alternative scenario given that activated T cells and Treg cells are known to regulate each other through IL-2 secretion and consumption, respectively.10,11,29,55,56 Therefore, in Cd25Y129H mice, impaired IL-2R signaling by autoreactive T cells may lead to decreased IL-2 production, which may be controlled by Treg cells even with low IL-2R activity, thereby maintaining the regulatory loop at a lower functional level.