Altered compartmentalization of transforming growth factor-beta in asthmatic airways

Clin Exp Allergy. 1997 Apr;27(4):389-95.


Background: Asthma is characterized by alterations of the bronchial epithelium associated with inflammatory cell infiltrates and sub-epithelial fibrosis. Transforming Growth Factor-beta (TGF-beta) is an anti-inflammatory and fibrosing cytokine normally present in bronchial epithelial cells and also potentially produced by inflammatory cells. Thus, TGF-beta could play a role in the asthmatic process, and its expression could be modified in asthmatic airways.

Objective: To test this latter hypothesis, we studied the bronchial distribution of TGF-beta in asthmatic patients.

Methods: TGF-beta 1, 2, 3 distribution was studied by immunohistochemistry in bronchial biopsies from 12 asthmatic patients and 10 non-asthmatic subjects.

Results: Bronchial epithelial cells from asthmatics were negative or faintly positive while a bright staining was detected in these from non-asthmatics (P < 0.01). In both groups, when inflammatory cells were present beneath the basement membrane, they were stained by the anti-TGF-beta antibody.

Conclusion: This study shows an altered compartimentalization of TGF-beta in asthma. (a) TGF-beta is scarse in asthmatic bronchial epithelial cells, which could favour the perennization of the bronchial inflammation, and (b) TGF-beta is present in inflammatory cells beneath the basement membrane, where it could be involved in the frequent sub-epithelial fibrosis.

MeSH terms

  • Adult
  • Aged
  • Asthma / immunology*
  • Asthma / metabolism*
  • Asthma / pathology
  • Basement Membrane / immunology
  • Basement Membrane / metabolism
  • Basement Membrane / pathology
  • Bronchi / immunology
  • Bronchi / metabolism*
  • Bronchi / pathology
  • Case-Control Studies
  • Epithelium / immunology
  • Epithelium / metabolism
  • Epithelium / pathology
  • Humans
  • Immunity, Mucosal
  • Immunohistochemistry
  • Middle Aged
  • Tissue Distribution
  • Transforming Growth Factor beta / metabolism*


  • Transforming Growth Factor beta