RIPK3 and infection: While ΔespL triggered a subtle increase in MLKL phosphorylation compared to wild-type C. rodentium infection in unprimed macrophages (Fig. 3A), LDH release following ΔespL infection remains comparable (Fig. 3B) between unprimed WT and the necroptosis-deficient MlklSA2 macrophages (EV3B,C), in which the two key RIPK3 phosphorylation sites (S345/347) on MLKL were replaced with alanine.