title: An in situ, in vivo murine model for the study of laryngotracheal stenosis.
abstract: OBJECTIVE
  Laryngotracheal stenosis (LTS) lacks an ideal animal model to study its unique wound-healing pathophysiology and the effect of interventions.
  
  
  OBJECTIVE
  To present an in vivo, in situ mouse model of LTS that can be used to investigate its pathophysiology, mechanisms, and interventions for treatment.
  
  
  METHODS
  Prospective controlled animal study performed at an academic animal research facility on 87 C57BL/6 mice.
  
  
  METHODS
  Experimental mice (n = 40) underwent bleomycin-coated wire-brush injury to the larynx and trachea, while mechanical injury controls (n = 32) underwent phosphate-buffered saline-coated wire-brush injury. Normal controls (n = 9) underwent no intervention, and mock surgery controls (n = 6) underwent anterior transcervical tracheal exposure only. Laryngotracheal complexes were harvested at days 7, 14, and 21 after injury. At the respective time points, mice in the chemomechanical and mechanical injury groups were killed, and their laryngotracheal complexes were harvested for histologic analysis. Normal and mock surgery controls were killed and then underwent histologic analysis.
  
  
  METHODS
  The primary outcome measure was lamina propria thickness.
  
  
  RESULTS
  The chemomechanical injury group maintained a significant increase in lamina propria thickness through day 21 compared with uninjured controls at day 7 (82.7 vs 41.8 μm; P<.05), day 14 (93.5 vs 26.0 μm; P<.05), and day 21 (91.2 vs 40.8 μm; P<.05). Compared with the mechanical injury group, the chemomechanical injury group demonstrated a significantly increased thickness at 21 days (91.2 vs 33.7 μm; P<.05).
  
  
  CONCLUSIONS
  Chemomechanical initiation of fibrosis in situ creates a viable mouse model of LTS that incorporates the physiologic circulatory supply and airflow. This small-animal model may be used to investigate the pathogenesis and inflammatory mechanisms of iatrogenic LTS and test therapeutic interventions to reverse or reduce the development of fibrosis.
authors.affiliation: Department of Otolaryngology-Head and Neck Surgery, Johns Hopkins University School of Medicine, Baltimore, Maryland.
authors.forename: Alexander T
authors.initials: AT
authors.lastname: Hillel
authors.affiliation: Department of Otolaryngology-Head and Neck Surgery, Johns Hopkins University School of Medicine, Baltimore, Maryland.
authors.forename: Daryan
authors.initials: D
authors.lastname: Namba
authors.affiliation: Department of Otolaryngology-Head and Neck Surgery, Johns Hopkins University School of Medicine, Baltimore, Maryland.
authors.forename: Dacheng
authors.initials: D
authors.lastname: Ding
authors.affiliation: Department of Otolaryngology-Head and Neck Surgery, Johns Hopkins University School of Medicine, Baltimore, Maryland.
authors.forename: Vinciya
authors.initials: V
authors.lastname: Pandian
authors.affiliation: Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, Maryland.
authors.forename: Jennifer H
authors.initials: JH
authors.lastname: Elisseeff
authors.affiliation: Division of Pulmonary and Critical Care Medicine, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland.
authors.forename: Maureen R
authors.initials: MR
authors.lastname: Horton
mesh_terms: D000818:Animals; D004195:Disease Models, Animal; D007829:Laryngostenosis / Q000503:physiopathology* / Q000601:surgery*; D051379:Mice; D008810:Mice, Inbred C57BL; D011446:Prospective Studies; D013194:Staining and Labeling