title: Transforming growth factor beta in normal human lung: preferential location in bronchial epithelial cells.
abstract: BACKGROUND
  Transforming growth factor beta (TGF-beta) is an immunomodulatory cytokine regulating the proliferation and differentiation of various cell types. It also contributes to the maintenance of tissue architecture by influencing the production of extracellular matrix components. TGF-beta has been detected in bronchoalveolar lavage fluid from normal human lung, but the nature and distribution of cells containing TGF-beta in this organ remain unknown.
  
  
  METHODS
  Fourteen normal human lung specimens were studied by immunohistochemistry with a monoclonal antibody recognizing TGF-beta 1, TGF-beta 2 and TGF-beta 3.
  
  
  RESULTS
  TGF-beta was detected in all cases. Bronchial epithelial cells contained the largest amounts of TGF-beta. In these cells the staining was brightest at the apical pole. Macrophages and smooth muscle cells also contained TGF-beta, although less than epithelial cells. No TGF-beta was detected in other cell populations, including endothelial cells, fibroblasts, and pneumocytes.
  
  
  CONCLUSIONS
  The bronchial epithelial compartment appears to be the main location of TGF-beta in the normal human lung, suggesting that this cytokine has a pivotal role in the immunological properties of the bronchial mucosa.
authors.affiliation: INSERM U 131, Clamart, France.
authors.forename: A
authors.initials: A
authors.lastname: Magnan
authors.forename: I
authors.initials: I
authors.lastname: Frachon
authors.forename: B
authors.initials: B
authors.lastname: Rain
authors.forename: M
authors.initials: M
authors.lastname: Peuchmaur
authors.forename: G
authors.initials: G
authors.lastname: Monti
authors.forename: B
authors.initials: B
authors.lastname: Lenot
authors.forename: M
authors.initials: M
authors.lastname: Fattal
authors.forename: G
authors.initials: G
authors.lastname: Simonneau
authors.forename: P
authors.initials: P
authors.lastname: Galanaud
authors.forename: D
authors.initials: D
authors.lastname: Emilie
mesh_terms: D000328:Adult; D000368:Aged; D001980:Bronchi / Q000737:chemistry*; D004848:Epithelium / Q000737:chemistry; D006801:Humans; D007150:Immunohistochemistry; D008264:Macrophages / Q000737:chemistry; D008875:Middle Aged; D009130:Muscle, Smooth / Q000737:chemistry; D016212:Transforming Growth Factor beta / Q000032:analysis*
chemical_list: D016212:Transforming Growth Factor beta