Studies from Sytwu’s group illustrated that Blimp-1 deficiency in T cells leads to higher numbers of activated CD4+ T cells, and this is associated with a homeostatic dysregulation of effector/memory T cells that contributes to both severe colitis in nonobese diabetic (NOD) mice and the exacerbation of autoimmune encephalomyelitis in myelin oligodendrocyte glycoprotein (MOG)35–55-immunized mice [35, 38, 39]. Here, PRDM1 is linked to colitis.