title: An ex vivo model of severe asthma using reconstituted human bronchial epithelium.
abstract: BACKGROUND
  Structural changes to the airways are features of severe asthma. The bronchial epithelium facilitates this remodeling process. Learning about the changes that develop in the airway epithelium could improve our understanding of asthma pathogenesis and lead to new therapeutic approaches.
  
  
  OBJECTIVE
  We sought to determine the feasibility and relevance of air-liquid interface cultures of bronchial epithelium derived from endobronchial biopsy specimens of patients with different severities of asthma for studying the airway epithelium.
  
  
  METHODS
  Human bronchial epithelial cells derived from endobronchial biopsy specimens of patients with mild and severe asthma were maintained in culture for 21 days in an air-liquid interface to reproduce a fully differentiated airway epithelium. Initially, features of remodeling that included epithelial and subepithelial layers, as well as mucus production, were assessed in paraffin-embedded endobronchial biopsy specimens to evaluate morphologic characteristics of asthmatic patients' epithelia. Ex vivo differentiated epithelia were then analyzed for morphology and function based on ultrastructural analysis, IL-8 release, lipoxin A(4) generation, mucin production, and lipoxygenase gene expression.
  
  
  RESULTS
  Morphologic and inflammatory imbalances initially observed in endobronchial biopsy specimens obtained from patients with severe or mild asthma persisted in the air-liquid interface reconstituted epithelium throughout the differentiation process to 21 days. Epithelium from patients with severe asthma produced greater levels of mucin, released more IL-8, and produced lower levels of lipoxin A(4) than that from patients with mild asthma. Expression of 15-lipoxygenase 2 was increased in epithelium from patients with severe asthma, whereas expression levels of MUC5AC, MUC5B, 5-lipoxygenase, and 15-lipoxygeanse 1 were similar to those of patients with mild asthma.
  
  
  CONCLUSIONS
  Ex vivo cultures of fully differentiated bronchial epithelium from endobronchial biopsy specimens maintain inherent phenotypic differences specifically related to the severity of asthma.
authors.affiliation: AP-HM Department of Respiratory diseases, Université Aix-Marseille, Marseille, France.
authors.forename: Delphine
authors.initials: D
authors.lastname: Gras
authors.forename: Arnaud
authors.initials: A
authors.lastname: Bourdin
authors.forename: Isabelle
authors.initials: I
authors.lastname: Vachier
authors.forename: Laure
authors.initials: L
authors.lastname: de Senneville
authors.forename: Caroline
authors.initials: C
authors.lastname: Bonnans
authors.forename: Pascal
authors.initials: P
authors.lastname: Chanez
mesh_terms: D000328:Adult; D000368:Aged; D056151:Airway Remodeling; D001249:Asthma / Q000276:immunology / Q000473:pathology* / Q000503:physiopathology; D001980:Bronchi / Q000473:pathology*; D018929:Cell Culture Techniques; D002454:Cell Differentiation; D002478:Cells, Cultured; D018450:Disease Progression; D005240:Feasibility Studies; D005260:Female; D006801:Humans; D016209:Interleukin-8 / Q000235:genetics / Q000378:metabolism; D044045:Lipoxins / Q000235:genetics / Q000378:metabolism; D008084:Lipoxygenase / Q000235:genetics / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D009077:Mucins / Q000378:metabolism; D020545:Respiratory Mucosa / Q000276:immunology / Q000473:pathology*; D055815:Young Adult
chemical_list: D016209:Interleukin-8; D044045:Lipoxins; D009077:Mucins; C040527:lipoxin A4; D008084:Lipoxygenase