IFNG and type 1 diabetes mellitus: NOD mice with genetic deletion of the IFN-γ gene (NOD.IFN-γ–/–, IFN-γ KO) showed significantly delayed onset of ICI-T1DM (Figure 2C; P < 0.0001 for anti–PD-1 therapy in WT versus IFN-γ KO mice).