IFNG and colitis: Interleukin (IL)-10-deficient mice display a Th1 colitis with elevated production of IL-12 and interferon (IFN)-γ in the early phase of disease, while in the late phase there is a progressive increase in the Th2 cytokines IL-4 and IL-13 [154]; similarly, in the SAMP1/YitFc model of ileitis, also a Th1 model of intestinal inflammation with an early elevation of IFN-γ and TNF-α production, the Th2 cytokines IL-5 and IL-13 significantly increase in the chronic stages of inflammation [155].