biostudies-literature00630Unknown215(9)Lee BLIntracellular LPS sensing by caspase-4/5/11 triggers proteolytic activation of pore-forming gasdermin D (GSDMD), leading to pyroptotic cell death in Gram-negative bacteria-infected cells. Involvement of caspase-4/5/11 and GSDMD in inflammatory responses, such as lethal sepsis, makes them highly desirable drug targets. Using knock-in (KI) mouse strains, we herein provide genetic evidence to show that caspase-11 auto-cleavage at the inter-subunit linker is essential for optimal catalytic activity and subsequent proteolytic cleavage of GSDMD. Macrophages from caspase-11-processing dead KI mice (Casp11Prc D285A/D285A ) exhibit defective caspase-11 auto-processing and phenocopy Casp11-/- and caspase-11 enzymatically dead KI (Casp11Enz C254A/C254A ) macrophages in attenuating responses to cytoplasmic LPS or Gram-negative bacteria infection. GsdmdD276A/D276A KI macrophages also fail to cleave GSDMD and are hypo-responsive to inflammasome stimuli, confirming that the GSDMD Asp276 residue is a nonredundant and indispensable site for proteolytic activation of GSDMD. Our data highlight the role of caspase-11 self-cleavage as a critical regulatory step for GSDMD processing and response against Gram-negative bacteria.The Journal of experimental medicine2279-2288https://www.ebi.ac.uk/biostudies/studies/S-EPMC6122968biostudies-literatureCaspase-11 auto-proteolysis is crucial for noncanonical inflammasome activation.PMC6122968Anderson KGupta ALee BLRoose-Girma MLee WPStowe IBKornfeld OSWarming SZhang JKayagaki N63falseCaspase-11 auto-proteolysis is crucial for noncanonical inflammasome activation.Intracellular LPS sensing by caspase-4/5/11 triggers proteolytic activation of pore-forming gasdermin D (GSDMD), leading to pyroptotic cell death in Gram-negative bacteria-infected cells. Involvement of caspase-4/5/11 and GSDMD in inflammatory responses, such as lethal sepsis, makes them highly desirable drug targets. Using knock-in (KI) mouse strains, we herein provide genetic evidence to show that caspase-11 auto-cleavage at the inter-subunit linker is essential for optimal catalytic activity and subsequent proteolytic cleavage of GSDMD. Macrophages from caspase-11-processing dead KI mice (Casp11Prc D285A/D285A ) exhibit defective caspase-11 auto-processing and phenocopy Casp11-/- and caspase-11 enzymatically dead KI (Casp11Enz C254A/C254A ) macrophages in attenuating responses to cytoplasmic LPS or Gram-negative bacteria infection. GsdmdD276A/D276A KI macrophages also fail to cleave GSDMD and are hypo-responsive to inflammasome stimuli, confirming that the GSDMD Asp276 residue is a nonredundant and indispensable site for proteolytic activation of GSDMD. Our data highlight the role of caspase-11 self-cleavage as a critical regulatory step for GSDMD processing and response against Gram-negative bacteria.2018-01-01T00:00:00Z2018 Sep2021-02-20T04:04:52Z2019-06-06T20:05:26ZS-EPMC61229683013507810.1084/jem.20180589