CD4 and type 1 diabetes mellitus: Autoimmune type 1 diabetes mellitus (T1DM) is a serious chronic autoimmune disease characterized by an absolute insulin deficiency, resulting from an depletion of insulin-secreting β cells located in pancreatic Langerhans’ islets mediated by autoantigen-specific CD4(+) and CD8(+) T-lymphocytes promoting further inflammation in this tissue [99–101].