IL2 and Autoimmunity: Given the aforementioned effects of IL-2 deficiency in the septohippocampal system, and the recent the finding from our lab that loss of brain-derived IL-2 (rather than peripheral of loss of IL-2 and autoimmunity) underlies the phenotypic loss of ChAT-positive cholinergic MS/vDB neurons in mice [19], we postulated that alterations in learning acquisition in IL-2KO would be associated largely with the loss of brain-derived IL-2.