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Salmonella infection induces recruitment of Caspase-8 to the inflammasome to modulate IL-1? production.

ABSTRACT: Nucleotide-binding oligomerization domain-like receptors (NLRs) detect pathogens and danger-associated signals within the cell. Salmonella enterica serovar Typhimurium, an intracellular pathogen, activates caspase-1 required for the processing of the proinflammatory cytokines, pro-IL-1? and pro-IL-18, and pyroptosis. In this study, we show that Salmonella infection induces the formation of an apoptosis-associated specklike protein containing a CARD (ASC)-Caspase-8-Caspase-1 inflammasome in macrophages. Caspase-8 and caspase-1 are recruited to the ASC focus independently of one other. Salmonella infection initiates caspase-8 proteolysis in a manner dependent on NLRC4 and ASC, but not NLRP3, caspase-1 or caspase-11. Caspase-8 primarily mediates the synthesis of pro-IL-1?, but is dispensable for Salmonella-induced cell death. Overall, our findings highlight that the ASC inflammasome can recruit different members of the caspase family to induce distinct effector functions in response to Salmonella infection.

SUBMITTER: Man SM

PROVIDER: S-EPMC3835177 | biostudies-literature | 2013 Nov

REPOSITORIES: biostudies-literature

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Salmonella infection induces recruitment of Caspase-8 to the inflammasome to modulate IL-1β production.

Man Si Ming SM Tourlomousis Panagiotis P Hopkins Lee L Monie Tom P TP Fitzgerald Katherine A KA Bryant Clare E CE

Journal of immunology (Baltimore, Md. : 1950) 20131011 10

Nucleotide-binding oligomerization domain-like receptors (NLRs) detect pathogens and danger-associated signals within the cell. Salmonella enterica serovar Typhimurium, an intracellular pathogen, activates caspase-1 required for the processing of the proinflammatory cytokines, pro-IL-1β and pro-IL-18, and pyroptosis. In this study, we show that Salmonella infection induces the formation of an apoptosis-associated specklike protein containing a CARD (ASC)-Caspase-8-Caspase-1 inflammasome in macro ...[more]

PMID: 24123685

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Dataset Information

Salmonella infection induces recruitment of Caspase-8 to the inflammasome to modulate IL-1? production.

Publications

Salmonella infection induces recruitment of Caspase-8 to the inflammasome to modulate IL-1β production.

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