CD4 and type 1 diabetes mellitus: While Th40 cells are present in non-autoimmune strains (up to 25%), they expand to approximately 60% of the CD4+ T cell compartment in non-obese diabetic (NOD) mice, a model for type 1 diabetes (T1D) and, coincidentally, a model for relapsing–remitting experimental autoimmune encephalomyelitis (EAE)13.