title: Neutrophils are a major source of the epithelial barrier disrupting cytokine oncostatin M in patients with mucosal airways disease.
abstract: BACKGROUND
  We have previously shown that oncostatin M (OSM) levels are increased in nasal polyps (NPs) of patients with chronic rhinosinusitis (CRS), as well as in bronchoalveolar lavage fluid, after segmental allergen challenge in allergic asthmatic patients. We also showed in vitro that physiologic levels of OSM impair barrier function in differentiated airway epithelium.
  
  
  OBJECTIVE
  We sought to determine which hematopoietic or resident cell type or types were the source of the OSM expressed in patients with mucosal airways disease.
  
  
  METHODS
  Paraffin-embedded NP sections were stained with fluorescence-labeled specific antibodies against OSM, GM-CSF, and hematopoietic cell-specific markers. Live cells were isolated from NPs and matched blood samples for flow cytometric analysis. Neutrophils were isolated from whole blood and cultured with the known OSM inducers GM-CSF and follistatin-like 1, and OSM levels were measured in the supernatants. Bronchial biopsy sections from control subjects, patients with moderate asthma, and patients with severe asthma were stained for OSM and neutrophil elastase.
  
  
  RESULTS
  OSM staining was observed in NPs, showed colocalization with neutrophil elastase (n = 10), and did not colocalize with markers for eosinophils, macrophages, T cells, or B cells (n = 3-5). Flow cytometric analysis of NPs (n = 9) showed that 5.1% ± 2% of CD45+cells were OSM+, and of the OSM+cells, 56% ± 7% were CD16+Siglec-8-, indicating neutrophil lineage. Only 0.6 ± 0.4% of CD45+events from matched blood samples (n = 5) were OSM+, suggesting that increased OSM levels in patients with CRS was locally stimulated and produced. A majority of OSM+neutrophils expressed arginase 1 (72.5% ± 12%), suggesting an N2 phenotype. GM-CSF levels were increased in NPs compared with those in control tissue and were sufficient to induce OSM production (P < .001) in peripheral blood neutrophils in vitro. OSM+neutrophils were also observed at increased levels in biopsy specimens from patients with severe asthma. Additionally, OSM protein levels were increased in induced sputum from asthmatic patients compared with that from control subjects (P < .05).
  
  
  CONCLUSIONS
  Neutrophils are a major source of OSM-producing cells in patients with CRS and severe asthma.
authors.affiliation: Division of Allergy-Immunology, Department of Medicine, Northwestern University Feinberg School of Medicine, Chicago, Ill.
authors.forename: Kathryn L
authors.initials: KL
authors.lastname: Pothoven
authors.affiliation: Division of Allergy-Immunology, Department of Medicine, Northwestern University Feinberg School of Medicine, Chicago, Ill.
authors.forename: James E
authors.initials: JE
authors.lastname: Norton
authors.affiliation: Division of Allergy-Immunology, Department of Medicine, Northwestern University Feinberg School of Medicine, Chicago, Ill.
authors.forename: Lydia A
authors.initials: LA
authors.lastname: Suh
authors.affiliation: Division of Allergy-Immunology, Department of Medicine, Northwestern University Feinberg School of Medicine, Chicago, Ill.
authors.forename: Roderick G
authors.initials: RG
authors.lastname: Carter
authors.affiliation: Division of Allergy-Immunology, Department of Medicine, Northwestern University Feinberg School of Medicine, Chicago, Ill.
authors.forename: Kathleen E
authors.initials: KE
authors.lastname: Harris
authors.affiliation: Division of Allergy-Immunology, Department of Medicine, Northwestern University Feinberg School of Medicine, Chicago, Ill.
authors.forename: Assel
authors.initials: A
authors.lastname: Biyasheva
authors.affiliation: Department of Otolaryngology, Northwestern University Feinberg School of Medicine, Chicago, Ill.
authors.forename: Kevin
authors.initials: K
authors.lastname: Welch
authors.affiliation: Department of Otolaryngology, Northwestern University Feinberg School of Medicine, Chicago, Ill.
authors.forename: Stephanie
authors.initials: S
authors.lastname: Shintani-Smith
authors.affiliation: Department of Otolaryngology, Northwestern University Feinberg School of Medicine, Chicago, Ill.
authors.forename: David B
authors.initials: DB
authors.lastname: Conley
authors.affiliation: Divisions of Allergy and Clinical Immunology, Pulmonary and Critical Care Medicine, Johns Hopkins Asthma and Allergy Center, Baltimore, Md.
authors.forename: Mark C
authors.initials: MC
authors.lastname: Liu
authors.affiliation: Division of Allergy-Immunology, Department of Medicine, Northwestern University Feinberg School of Medicine, Chicago, Ill.
authors.forename: Atsushi
authors.initials: A
authors.lastname: Kato
authors.affiliation: Division of Allergy-Immunology, Department of Medicine, Northwestern University Feinberg School of Medicine, Chicago, Ill.
authors.forename: Pedro C
authors.initials: PC
authors.lastname: Avila
authors.affiliation: Meakins-Christie Laboratories of McGill University and McGill University Health Center Research Institute, Montreal, Quebec, Canada.
authors.forename: Qutayba
authors.initials: Q
authors.lastname: Hamid
authors.affiliation: Division of Allergy-Immunology, Department of Medicine, Northwestern University Feinberg School of Medicine, Chicago, Ill.
authors.forename: Leslie C
authors.initials: LC
authors.lastname: Grammer
authors.affiliation: Division of Allergy-Immunology, Department of Medicine, Northwestern University Feinberg School of Medicine, Chicago, Ill.
authors.forename: Anju T
authors.initials: AT
authors.lastname: Peters
authors.affiliation: Division of Allergy-Immunology, Department of Medicine, Northwestern University Feinberg School of Medicine, Chicago, Ill.
authors.forename: Robert C
authors.initials: RC
authors.lastname: Kern
authors.affiliation: Department of Otolaryngology, Northwestern University Feinberg School of Medicine, Chicago, Ill.
authors.forename: Bruce K
authors.initials: BK
authors.lastname: Tan
authors.affiliation: Division of Allergy-Immunology, Department of Medicine, Northwestern University Feinberg School of Medicine, Chicago, Ill; Department of Otolaryngology, Northwestern University Feinberg School of Medicine, Chicago, Ill. Electronic address: rpschleimer@northwestern.edu.
authors.forename: Robert P
authors.initials: RP
authors.lastname: Schleimer
mesh_terms: D000328:Adult; D000368:Aged; D001249:Asthma / Q000276:immunology*; D001980:Bronchi / Q000166:cytology; D002478:Cells, Cultured; D002908:Chronic Disease; D004847:Epithelial Cells / Q000276:immunology; D005260:Female; D016178:Granulocyte-Macrophage Colony-Stimulating Factor / Q000276:immunology; D006801:Humans; D019272:Leukocyte Elastase / Q000276:immunology; D008297:Male; D008875:Middle Aged; D009298:Nasal Polyps / Q000276:immunology*; D009504:Neutrophils / Q000276:immunology*; D053683:Oncostatin M / Q000276:immunology*; D020545:Respiratory Mucosa / Q000276:immunology; D012220:Rhinitis / Q000276:immunology*; D012852:Sinusitis / Q000276:immunology*; D013211:Staphylococcus aureus; D055815:Young Adult
chemical_list: D053683:Oncostatin M; D016178:Granulocyte-Macrophage Colony-Stimulating Factor; D019272:Leukocyte Elastase
keywords: Oncostatin M; atopic asthma; chronic rhinosinusitis; epithelial barrier; granulocyte-monocyte colony-stimulating factor; neutrophils