Functional characteristics of bronchial epithelium obtained by brushing from asthmatic and normal subjects

Am Rev Respir Dis. 1993 Mar;147(3):529-34. doi: 10.1164/ajrccm/147.3.529.


Airways epithelial cells may be involved in the pathogenesis of asthma, but their role remains to be determined. Epithelial cells can release large amounts of 15-hydroxy-eicosatetranoic acid (15-HETE) and smaller amounts of prostaglandin E2 (PGE2) as well as fibronectin, a mediator involved in epithelial repair after injury. Epithelial cells obtained after bronchial brushing of 16 asthmatic (age 38 +/- 5 yr) and 11 normal subjects (age 36 +/- 5 yr) were studied. The percentage of epithelial cells was assessed by immunocytochemistry using an anti-cytokeratin antibody. The viability of the cells was assessed by trypan blue exclusion. The release of 15-HETE PGE2 and fibronectin was studied in resting cells and after A23187 calcium ionophore stimulation. Epithelial cells always comprised more than 86% of cells recovered, and the viability of epithelial cells was significantly (p < 0.001, Mann-Whitney U test) greater in normal subjects (54 +/- 5%) compared with asthmatic subjects (13 +/- 1%). The release of 15-HETE and fibronectin by resting epithelial cells was significantly greater in asthmatics (p < 0.05, Mann-Whitney U test) than in normal subjects. A23187 significantly (p < 0.05, Wilcoxon W test) increased the release of 15-HETE and fibronectin. There was no significant difference in the release of PGE2 by resting cells from either asthmatics or normal subjects, but challenge with A23187 induced a significant (p < 0.03, Wilcoxon W test) increase in PGE2 from cells of asthmatics but not from cells of normal subjects. This study shows that epithelial cells are activated and less viable in asthma and suggests a role for these cells in asthma.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Albuterol / pharmacology
  • Asthma / etiology
  • Asthma / physiopathology*
  • Bronchi / cytology
  • Bronchi / drug effects
  • Bronchi / physiopathology*
  • Bronchoalveolar Lavage Fluid / cytology
  • Bronchoscopy
  • Calcimycin / pharmacology
  • Cell Survival / drug effects
  • Dinoprostone / analysis
  • Epithelial Cells
  • Epithelium / drug effects
  • Epithelium / physiopathology
  • Fiber Optic Technology
  • Fibronectins / analysis
  • Fibronectins / drug effects
  • Humans
  • Hydroxyeicosatetraenoic Acids / analysis


  • Fibronectins
  • Hydroxyeicosatetraenoic Acids
  • Calcimycin
  • 15-hydroxy-5,8,11,13-eicosatetraenoic acid
  • Dinoprostone
  • Albuterol