NOX2 protects against prolonged inflammation, lung injury, and mortality following systemic insults.

Abstract

The systemic inflammatory response syndrome (SIRS) is a clinical condition occurring in intensive care unit patients as a consequence of both infectious and noninfectious insults. The mechanisms underlying resolution of SIRS are not well characterized. NOX2 (NADPH oxidase 2)-derived reactive oxygen species are critical for killing of certain pathogens by polymorphonuclear leukocytes (PMN). Patients with chronic granulomatous disease who lack functional NOX2 are not only prone to serious infections, they also exhibit chronic inflammatory conditions, suggesting a local anti-inflammatory role for NOX2. We hypothesized that NOX2 is required for the resolution of sterile systemic inflammation. Using a murine model of sterile generalized inflammation, we observed dramatically increased mortality of gp91(phox-/y) (NOX2-deficient) as compared to wild-type (WT) mice. Both genotypes developed robust SIRS with hypothermia, hypotension, and leukopenia; however, WT mice recovered within 48 h whereas NOX2-deficient mice did not. Although both groups displayed rapid peritoneal PMN recruitment, the recruited NOX2-deficient PMN demonstrated an enhanced inflammatory phenotype. Moreover, NOX2-deficient mice exhibited a hemorrhagic inflammatory response in the lungs with rapid and persistent recruitment of neutrophils to the alveolar space, whereas WT mice had minimal lung pathology. Several proinflammatory cytokines remained elevated in NOX2-deficient mice. The persistent inflammatory environment observed in NOX2-deficient mice resulted from continued peritoneal chemokine secretion and not delayed apoptosis of PMN. These data suggest a requirement for NOX2 in the resolution of systemic inflammation.

• Authors: Laura C Whitmore, Brieanna M Hilkin, Kelli L Goss, Erin M Wahle, Tarah T Colaizy, Paola M Boggiatto, Steven M Varga, Francis J Miller, Jessica G Moreland
• Journal: Journal of innate immunity (J Innate Immun) Vol. 5 Issue 6 Pg. 565-80 ( 2013) ISSN: 1662-8128 [Electronic] Switzerland
• PMID: 23635512 (Publication Type: Journal Article, Research Support, N.I.H., Extramural, Research Support, Non-U.S. Gov't, Research Support, U.S. Gov't, Non-P.H.S.)
• Copyright: Copyright © 2013 S. Karger AG, Basel.

Chemical References

• Cytokines
• Membrane Glycoproteins
• Cybb protein, mouse
• NADPH Oxidase 2
• NADPH Oxidases

Topics

• Animals
• Apoptosis (genetics, immunology)
• Cytokines (blood, immunology, metabolism)
• Flow Cytometry
• Inflammation (genetics, immunology, metabolism)
• Kaplan-Meier Estimate
• Lung (immunology, metabolism, pathology)
• Lung Injury (genetics, immunology, metabolism)
• Male
• Membrane Glycoproteins (genetics, immunology, metabolism)
• Mice
• Mice, 129 Strain
• Mice, Inbred C57BL
• Mice, Knockout
• NADPH Oxidase 2
• NADPH Oxidases (genetics, immunology, metabolism)
• Neutrophil Infiltration (genetics, immunology)
• Peritoneum (immunology, metabolism)
• Systemic Inflammatory Response Syndrome (genetics, immunology, metabolism)
• T-Lymphocytes (immunology, metabolism)