title: Myofibroblast persistence and collagen type I accumulation in the human stenotic trachea.
abstract: BACKGROUND
  Postintubation tracheal stenosis (PITS) is associated with an increased use of assisted ventilation in intensive care units. We investigated both collagen type I accumulation and myofibroblast localization in human PITS lesions excised for surgical therapeutic procedures, compared with normal tracheas.
  
  
  METHODS
  We analyzed 2 segments of normal tracheas and 10 segments of PITS that were stained by hematoxylin-eosin and picrosirius red techniques and processed for immunohistochemistry using antibodies against both α-smooth muscle actin (α-sma) for myofibroblast detection, and collagen type I.
  
  
  RESULTS
  We showed a significant increase in collagen deposition in PITS specimens compared with normal tracheas. We found spindle-shaped α-sma-positive cells (myofibroblasts) in the subepithelial layer of all pathologic tracheas, and the persistence of an intense myofibroblast network at PITS sites.
  
  
  CONCLUSIONS
  Tracheal wall thickening in PITS is due to a deranged collagen remodeling that is related to myofibroblast activation.
authors.affiliation: Instituto de Ciências Biomédicas, Centro de Ciências da Saúde, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil.
authors.forename: João Gustavo
authors.initials: JG
authors.lastname: Corrêa Reis
authors.forename: Christina Maeda
authors.initials: CM
authors.lastname: Takiya
authors.forename: Antonia
authors.initials: A
authors.lastname: Lima Carvalho
authors.forename: Rafael
authors.initials: R
authors.lastname: Souza Mota
authors.forename: Bernardo
authors.initials: B
authors.lastname: De-Ary-Pires
authors.forename: Mário Ary
authors.initials: MA
authors.lastname: Pires-Neto
authors.forename: Ricardo
authors.initials: R
authors.lastname: de Ary-Pires
mesh_terms: D000328:Adult; D002454:Cell Differentiation; D024042:Collagen Type I / Q000378:metabolism*; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008875:Middle Aged; D058628:Myofibroblasts / Q000166:cytology* / Q000378:metabolism; D014132:Trachea / Q000378:metabolism* / Q000473:pathology; D014135:Tracheal Stenosis / Q000378:metabolism* / Q000473:pathology; D055815:Young Adult
chemical_list: D024042:Collagen Type I