CD4 and type 1 diabetes mellitus: The possible mechanisms of protection against T1DM involve the conversion from Th1 to Th2 response, the activation of Treg (CD4+CD25+FoxP3+ T cells) and Breg (CD5+CD19+B cells), the decrease of IFN-γ and IL-2, and the promotion of IL-4, IL-5, IL-10, and TGF-β, all of which are capable of inhibiting T1DM pathology [35, 69, 71, 72].