CD4 and Autoimmunity: Studies on B and T cell immune dysregulation found many possible responsible factors for autoimmunity appearance, such as the expansion of CD21low/- B cells and related reduction of T regulatory cells (22); the reduction of switched memory B cells (23, 24); the low levels of naïve CD8+ (25) and CD4+ (22, 25, 26) T cells and the elevated T helper 1 and IFN gamma signature (27), related to the increase in T helper 1 and follicular T CD4+ cells (28, 29).