title: Asthmatic airway epithelial cells differentially regulate fibroblast expression of extracellular matrix components.
abstract: BACKGROUND
  Airway remodeling might explain lung function decline among asthmatic children. Extracellular matrix (ECM) deposition by human lung fibroblasts (HLFs) is implicated in airway remodeling. Airway epithelial cell (AEC) signaling might regulate HLF ECM expression.
  
  
  OBJECTIVE
  We sought to determine whether AECs from asthmatic children differentially regulate HLF expression of ECM constituents.
  
  
  METHODS
  Primary AECs were obtained from well-characterized atopic asthmatic (n = 10) and healthy (n = 10) children intubated during anesthesia for an elective surgical procedure. AECs were differentiated at an air-liquid interface for 3 weeks and then cocultured with HLFs from a healthy child for 96 hours. Collagen I (COL1A1), collagen III (COL3A1), hyaluronan synthase (HAS) 2, and fibronectin expression by HLFs and prostaglandin E2 synthase (PGE2S) expression by AECs were assessed by using RT-PCR. TGF-β1 and TGF-β2 concentrations in media were measured by using ELISA.
  
  
  RESULTS
  COL1A1 and COL3A1 expression by HLFs cocultured with AECs from asthmatic patients was greater than that by HLFs cocultured with AECs from healthy subjects (2.2-fold, P < .02; 10.8-fold, P < .02). HAS2 expression by HLFs cocultured with AECs from asthmatic patients was 2.5-fold higher than that by HLFs cocultured with AECs from healthy subjects (P < .002). Fibronectin expression by HLFs cocultured with AECs from asthmatic patients was significantly greater than that by HLFs alone. TGF-β2 activity was increased in cocultures of HLFs with AECs from asthmatic patients (P < .05), whereas PGES2 was downregulated in AEC-HLF cocultures (2.2-fold, P < .006).
  
  
  CONCLUSIONS
  HLFs cocultured with AECs from asthmatic patients showed differential expression of the ECM constituents COL1A1 and COL3A1 and HAS2 compared with HLFs cocultured with AECs from healthy subjects. These findings support a role for altered ECM production in asthmatic airway remodeling, possibly regulated by unbalanced AEC signaling.
authors.affiliation: Division of Pulmonary Medicine, Seattle Children's Hospital, University of Washington, Seattle, Wash; Center for Immunity and Immunotherapies, Seattle Children's Research Institute, Seattle, Wash.
authors.forename: Stephen R
authors.initials: SR
authors.lastname: Reeves
authors.affiliation: Center for Immunity and Immunotherapies, Seattle Children's Research Institute, Seattle, Wash.
authors.forename: Tessa
authors.initials: T
authors.lastname: Kolstad
authors.affiliation: Center for Immunity and Immunotherapies, Seattle Children's Research Institute, Seattle, Wash.
authors.forename: Tin-Yu
authors.initials: TY
authors.lastname: Lien
authors.affiliation: Division of Pulmonary Medicine, Seattle Children's Hospital, University of Washington, Seattle, Wash; Center for Immunity and Immunotherapies, Seattle Children's Research Institute, Seattle, Wash.
authors.forename: Molly
authors.initials: M
authors.lastname: Elliott
authors.affiliation: Benaroya Research Institute, Seattle, Wash.
authors.forename: Steven F
authors.initials: SF
authors.lastname: Ziegler
authors.affiliation: Benaroya Research Institute, Seattle, Wash.
authors.forename: Thomas N
authors.initials: TN
authors.lastname: Wight
authors.affiliation: Division of Pulmonary Medicine, Seattle Children's Hospital, University of Washington, Seattle, Wash; Center for Immunity and Immunotherapies, Seattle Children's Research Institute, Seattle, Wash. Electronic address: jason.debley@seattlechildrens.org.
authors.forename: Jason S
authors.initials: JS
authors.lastname: Debley
mesh_terms: D000293:Adolescent; D056151:Airway Remodeling / Q000502:physiology; D002450:Cell Communication; D002478:Cells, Cultured; D002648:Child; D018920:Coculture Techniques; D024042:Collagen Type I / Q000235:genetics / Q000378:metabolism; D000090602:Collagen Type I, alpha 1 Chain; D024061:Collagen Type III / Q000235:genetics / Q000378:metabolism; D005109:Extracellular Matrix / Q000378:metabolism*; D005260:Female; D005347:Fibroblasts / Q000473:pathology / Q000502:physiology*; D005353:Fibronectins / Q000235:genetics / Q000378:metabolism; D005786:Gene Expression Regulation; D014453:Glucuronosyltransferase / Q000235:genetics / Q000378:metabolism; D006801:Humans; D000076002:Hyaluronan Synthases; D019746:Intramolecular Oxidoreductases / Q000235:genetics / Q000378:metabolism; D008168:Lung / Q000473:pathology*; D008297:Male; D000071876:Prostaglandin-E Synthases; D020545:Respiratory Mucosa / Q000502:physiology*; D053773:Transforming Growth Factor beta1 / Q000378:metabolism; D053781:Transforming Growth Factor beta2 / Q000378:metabolism
chemical_list: C439971:COL3A1 protein, human; D024042:Collagen Type I; D000090602:Collagen Type I, alpha 1 Chain; D024061:Collagen Type III; D005353:Fibronectins; D053773:Transforming Growth Factor beta1; D053781:Transforming Growth Factor beta2; D014453:Glucuronosyltransferase; C101754:HAS2 protein, human; D000076002:Hyaluronan Synthases; D019746:Intramolecular Oxidoreductases; D000071876:Prostaglandin-E Synthases
keywords: Asthma; TGF-β2; airway remodeling; children; collagen I; collagen III; epithelial cells; extracellular matrix; fibronectin; human lung fibroblasts; hyaluronic acid