CASP4 and infection: The Shigella effector OspC3 antagonizes the human LPS sensor CASP4 (Kobayashi et al., 2013), and IEC-expressed CASP4 provides protection against other human bacterial pathogens (Holly et al., 2020; Knodler et al., 2014), underscoring the importance of the LPS-sensing pathway during human infection.