CASP8 and dermatitis: Epidermal-specific caspase-8 or FADD loss causes necroptotic skin lesions.45, 111 Hence, it was somewhat surprising that the dermatitis featured in Sharpincpdm/cpdm mice is driven by TNF-induced keratinocyte apoptosis, as shown by the absence of lesions upon epidermal-specific deletion of FADD (on a Ripk3−/− background) or heterozygous deletion of caspase-8, but not MLKL loss.110, 112 In contrast, other disease manifestations were driven by both apoptotic and necroptotic signalling.