CASP1 and colitis: Given the lethality phenotype of Casp8–/–Ripk3–/–Casp1/11–/– mice, we next investigated colitis at 8 dpi in these mice as well as in their Casp8+/-Ripk3–/–Casp1/11+/- and Casp8–/–Ripk3–/–Casp1/11+/- littermates to evaluate potential cumulative effects of Casp8 and Casp1/11 deletion on a Ripk3–/– background.