A Murine Model of Airway Granulation and Subglottic Stenosis

Abstract

Objectives: The murine model, in which tracheas are transplanted into the subcutaneous tissue of recipient mice and subsequently studied for signs of granulation tissue, has been particularly successful in studying airway disease. Mouse laryngotracheal complexes (LTC’s) will undergo airway injury and transplantation into syngeneic recipient mice in order to develop a functional model of airway granulation tissue and subglottic stenosis. Study Design: IACUC (Institutional Animal Care and Use Committee) approved animal study Methods: The LTC’s of donor mice underwent direct airway injury through mucosal scraping using a wire brush or through application of hydrochloric acid (HCl) solution to the mucosa. A control group did not undergo any airway injury. LTC’s were harvested and transplanted heterotopically into the subcutaneous tissue of syngeneic recipient mice and harvested at 3 weeks posttransplantation. Harvested LTC’s underwent analysis by standard histochemistry using trichrome staining, specifically to highlight collagen formation and thus to examine degree of granulation tissue in the experimental groups compared to the control group. Results: At 3 weeks posttransplantation, trichrome staining showed that direct injury of the airway epithelium, both mechanically using a wire brush and chemically using HCl solution, results in the formation of granulation under the disrupted airway epithelium, with narrowing of the airway lumen and evidence of early fibrosis. Conclusions: The development of a murine model of airway granulation tissue is an efficient tool for characterizing the process and for establishing strategies to prevent granulation and subglottic stenosis. A Murine Model of Airway Granulation and Subglottic Stenosis