CASP6 regulates pyroptosis during gram-negative bacterial infections. A and B, real-time analysis of cell death in bone marrow-derived macrophages (BMDMs) using the IncuCyte imaging system and SYTOX Green nucleic acid staining after infection with Escherichia coli (20 MOI) (A) or Citrobacter rodentium (20 MOI) (B). quantification of the cell death at the indicated timepoints is shown. C, immunoblot analysis of pro- (p45) and cleaved caspase-1 (p20; CASP1), pro- (p53) and cleaved gasdermin D (p30; GSDMD), and pro- (p43) and cleaved caspase-11 (p38 and p26; CASP11) and caspase-6 (CASP6) in BMDMs after E. coli (20 MOI) infection for the indicated time. GAPDH was used as the internal control. D, immunoblot analysis of pro- and cleaved CASP1, pro- and cleaved GSDMD, and pro- and cleaved CASP11 and CASP6 in BMDMs after C. rodentium (20 MOI) infection for the indicated time. Asterisk indicates a nonspecific band. GAPDH was used as the internal control. The data are representative of at least three independent experiments. The data are shown as mean ± SEM (A and B). CASP, caspase; MOI, multiplicity of infection.