title: Cigarette smoke modulates PGE(2) and host defence against Moraxella catarrhalis infection in human airway epithelial cells.
abstract: OBJECTIVE
  Airway bacterial infections pose a significant challenge to the management of COPD, a disease mainly caused by cigarette smoking. However, the mechanisms of impaired airway mucosal innate immunity against bacteria in COPD remain unclear. We examined the effect of cigarette smoke on prostaglandin E(2) (PGE(2)) and downstream epithelial host defence mechanisms including the antimicrobial substance human β-defensin-2 (hBD-2).
  
  
  METHODS
  Brushed bronchial epithelial cells were obtained from healthy smokers and individuals with COPD, and cultured under air-liquid interface conditions with or without exposure to whole cigarette smoke (WCS) or Moraxella catarrhalis (Mc) infection. Bacterial load, hBD-2 (a molecule known to kill Mc) and PGE(2) were measured.
  
  
  RESULTS
  WCS decreased Mc-induced hBD-2 expression and increased Mc load on bronchial epithelial cells from healthy smokers and COPD patients. Moreover, WCS inhibited PGE(2) induction following Mc. PGE(2) was shown to increase hBD-2 production in bronchial epithelial cells from healthy smokers, but not from COPD patients.
  
  
  CONCLUSIONS
  The results suggest that in well-differentiated human bronchial epithelial cells, WCS may impair host defence against Mc in part through inhibiting PGE(2) production.
authors.affiliation: School of Medicine, Nanjing University, Nanjing, China.
authors.forename: Weiyun
authors.initials: W
authors.lastname: Zhang
authors.forename: Stephanie
authors.initials: S
authors.lastname: Case
authors.forename: Russell P
authors.initials: RP
authors.lastname: Bowler
authors.forename: Richard J
authors.initials: RJ
authors.lastname: Martin
authors.forename: Di
authors.initials: D
authors.lastname: Jiang
authors.forename: Hong Wei
authors.initials: HW
authors.lastname: Chu
mesh_terms: D001980:Bronchi / Q000276:immunology / Q000378:metabolism / Q000382:microbiology; D002478:Cells, Cultured; D015232:Dinoprostone / Q000096:biosynthesis / Q000276:immunology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D001936:Moraxella catarrhalis / Q000276:immunology*; D045828:Moraxellaceae Infections / Q000276:immunology*; D029424:Pulmonary Disease, Chronic Obstructive / Q000188:drug therapy / Q000276:immunology / Q000382:microbiology; D020545:Respiratory Mucosa / Q000276:immunology / Q000378:metabolism / Q000382:microbiology; D012907:Smoking / Q000276:immunology*; D023083:beta-Defensins / Q000096:biosynthesis
chemical_list: C106641:DEFB4A protein, human; D023083:beta-Defensins; D015232:Dinoprostone