CD4 and Autoimmunity: Collectively, these data demonstrate that Stat1T385M increased basal and cytokine-stimulated Stat1 activation in lymphocytes, disrupting naïve CD4 T cell homeostasis and promoting differentiation of abnormal T helper cells with cytotoxic features (63) as well as GC-like B cells, eventually resulting in autoimmunity in the absence of overt infection.