The role of respiratory epithelium in a rat model of obliterative airway disease

Background. The etiology and pathogenesis of obliterative bronchiolitis aft er lung transplantation remain to be fully elucidated. Using a rat model of heterotopically transplanted trachea grafts, we have examined the role air way epithelium plays in obliterative airway disease (OAD). Methods. Rat trachea isografts were denuded of epithelium by protease diges tion. Grafts were inoculated either with or without native airway epithelia l cells and transplanted into the omentum of recipient animals. Results. Airway epithelium removal resulted in OAD in denuded isogeneic tra chea grafts. Reseeding of the denuded grafts with epithelial cells signific antly reduced airway obliteration from 78% to 22% luminal occlusion. Conclusions. Non-immune-mediated injury will cause OAD, and epithelial cell replacement in denuded isografts can significantly reduce the fibrotic pro gression of the disease.