title: Inflammasome-mediated cell death in response to bacterial pathogens that access the host cell cytosol: lessons from legionella pneumophila.
abstract: Cell death can be critical for host defense against intracellular pathogens because it eliminates a crucial replicative niche, and pro-inflammatory cell death can alert neighboring cells to the presence of pathogenic organisms and enhance downstream immune responses. Pyroptosis is a pro-inflammatory form of cell death triggered by the inflammasome, a multi-protein complex that assembles in the cytosol to activate caspase-1. Inflammasome activation by pathogens hinges upon violation of the host cell cytosol by activities such as the use of pore-forming toxins, the use of specialized secretion systems, or the cytosolic presence of the pathogen itself. Recently, a non-canonical inflammasome has been described that activates caspase-11 and also leads to pro-inflammatory cell death. Caspase-11 is activated rapidly and robustly in response to violation of the cytosol by bacterial pathogens as well. In this mini-review, we describe the canonical and non-canonical inflammasome pathways that are critical for host defense against a model intracellular bacterial pathogen that accesses the host cytosol-Legionella pneumophila.
authors.affiliation: Department of Microbiology, Perelman School of Medicine, University of Pennsylvania Philadelphia, PA, USA.
authors.forename: Cierra N
authors.initials: CN
authors.lastname: Casson
authors.affiliation: Department of Microbiology, Perelman School of Medicine, University of Pennsylvania Philadelphia, PA, USA.
authors.forename: Sunny
authors.initials: S
authors.lastname: Shin
mesh_terms: D020169:Caspases / Q000276:immunology / Q000378:metabolism*; D016923:Cell Death; D003600:Cytosol / Q000382:microbiology*; D058847:Inflammasomes / Q000276:immunology / Q000378:metabolism*; D016952:Legionella pneumophila / Q000276:immunology*; D007877:Legionnaires' Disease / Q000276:immunology* / Q000382:microbiology*
chemical_list: D058847:Inflammasomes; D020169:Caspases
keywords: Legionella pneumophila; caspase-1; caspase-11; cell death; inflammasome; pyroptosis