The Listeria monocytogenes InlC protein interferes with innate immune responses by targeting the IκB kinase subunit IKKα

• DOI: 10.1073/pnas.1007765107
• Publication Date: 2010-09-21T04:37:18Z
• Authors: Edith Gouin; Minou Adib-Conquy; Damien Balestrino; Marie-Anne Nahori; Véronique Villiers; Frédéric Colland; Shaynoor Dramsi; Olivier Dussurget; Pascale Cossart
• Keywords: IκB kinase; Proinflammatory cytokine; Listeria infection

Listeria monocytogenes is an intracellular pathogen responsible for severe foodborne infections. It can replicate in both phagocytic and nonphagocytic mammalian cells. The infectious process at the cellular level has been studied extensively, but how bacterium overcomes early host innate immune responses remains largely unknown. Here we show that InlC, a member of internalin family, secreted intracellularly directly interacts with IKKα, subunit IκB kinase complex critical phosphorylation activation NF-κB, major regulator responses. Infection experiments WT or inlC -deletion mutant transfection cells InlC reveal expression impairs consequently delays degradation normally induced by TNF-α, classical NF-κB stimulator. Moreover, infection RAW 264.7 macrophages leads to increased production proinflammatory cytokines compared obtained WT. Finally, peritonitis mouse model, induces chemokines recruitment neutrophils peritoneal cavity Together, these results demonstrate interacting dampens response during process.