title: Bacteria-specific neutrophil dysfunction associated with interferon-stimulated gene expression in the acute respiratory distress syndrome.
abstract: Acute respiratory distress syndrome (ARDS) is a poorly understood condition with greater than 30% mortality. Massive recruitment of neutrophils to the lung occurs in the initial stages of the ARDS. Significant variability in the severity and duration of ARDS-associated pulmonary inflammation could be linked to heterogeneity in the inflammatory capacity of neutrophils. Interferon-stimulated genes (ISGs) are a broad gene family induced by Type I interferons. While ISGs are central to anti-viral immunity, the potential exists for these genes to evoke extensive modification in cellular response in other clinical settings. In this prospective study, we sought to determine if ISG expression in circulating neutrophils from ARDS patients is associated with changes in neutrophil function. Circulating neutrophil RNA was isolated, and hierarchical clustering ranked patients' expression of three ISGs. Neutrophil response to pathogenic bacteria was compared between normal and high ISG-expressing neutrophils. High neutrophil ISG expression was found in 25 of 95 (26%) of ARDS patients and was associated with reduced migration toward interleukin-8, and altered responses to Staphylococcus aureus, but not Pseudomonas aeruginosa, which included decreased p38 MAP kinase phosphorylation, superoxide anion release, interleukin-8 release, and a shift from necrotic to apoptotic cell death. These alterations in response were reflected in a decreased capacity to kill S. aureus, but not P. aeruginosa. Therefore, the ISG expression signature is associated with an altered circulating neutrophil response phenotype in ARDS that may predispose a large subgroup of patients to increased risk of specific bacterial infections.
authors.affiliation: Department of Medicine, National Jewish Health, Denver, Colorado, United States of America. malcolmk@njhealth.org
authors.forename: Kenneth C
authors.initials: KC
authors.lastname: Malcolm
authors.forename: Jennifer E
authors.initials: JE
authors.lastname: Kret
authors.forename: Robert L
authors.initials: RL
authors.lastname: Young
authors.forename: Katie R
authors.initials: KR
authors.lastname: Poch
authors.forename: Silvia M
authors.initials: SM
authors.lastname: Caceres
authors.forename: Ivor S
authors.initials: IS
authors.lastname: Douglas
authors.forename: Chris D
authors.initials: CD
authors.lastname: Coldren
authors.forename: Ellen L
authors.initials: EL
authors.lastname: Burnham
authors.forename: Marc
authors.initials: M
authors.lastname: Moss
authors.forename: Jerry A
authors.initials: JA
authors.lastname: Nick
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016923:Cell Death / Q000187:drug effects; D002465:Cell Movement / Q000187:drug effects; D002469:Cell Separation; D015331:Cohort Studies; D005260:Female; D005786:Gene Expression Regulation / Q000187:drug effects*; D006801:Humans; D007372:Interferons / Q000494:pharmacology*; D016209:Interleukin-8 / Q000378:metabolism; D008297:Male; D050296:Microbial Viability / Q000187:drug effects; D008875:Middle Aged; D009504:Neutrophils / Q000187:drug effects / Q000201:enzymology / Q000473:pathology*; D012128:Respiratory Distress Syndrome / Q000235:genetics* / Q000382:microbiology* / Q000503:physiopathology / Q000821:virology; D013045:Species Specificity; D013211:Staphylococcus aureus / Q000187:drug effects / Q000276:immunology*; D013481:Superoxides / Q000378:metabolism; D014780:Viruses / Q000187:drug effects / Q000276:immunology; D055815:Young Adult; D048051:p38 Mitogen-Activated Protein Kinases / Q000378:metabolism
chemical_list: D016209:Interleukin-8; D013481:Superoxides; D007372:Interferons; D048051:p38 Mitogen-Activated Protein Kinases