Neutrophil elastase modulates cytokine expression: contribution to host defense against Pseudomonas aeruginosa-induced pneumonia.

ABSTRACT: There is accumulating evidence that following bacterial infection, the massive recruitment and activation of the phagocytes, neutrophils, is accompanied with the extracellular release of active neutrophil elastase (NE), a potent serine protease. Using NE-deficient mice in a clinically relevant model of Pseudomonas aeruginosa-induced pneumonia, we provide compelling in vivo evidence that the absence of NE was associated with decreased protein and transcript levels of the proinflammatory cytokines TNF-α, MIP-2, and IL-6 in the lungs, coinciding with increased mortality of mutant mice to infection. The implication of NE in the induction of cytokine expression involved at least in part Toll-like receptor 4 (TLR-4). These findings were further confirmed following exposure of cultured macrophage

SUBMITTER: Benabid R 

PROVIDER: S-EPMC3471768 | biostudies-literature | 2012 Oct

REPOSITORIES: biostudies-literature