XENOTRANSPLANTED IN VIVO CULTURE MODEL OF MUCOUS CELL HYPERPLASIA IN RESPIRATORY EPITHELIUM INDUCED BY HUMAN NEUTROPHIL ELASTASE

This study was conducted to establish a novel model of airway mucous cell hyperplasia and mucous hypersecretion suitable for both morphological and physico-biochemical examinations, using a xenotransplanted in vivo culture system. Tracheal epithelial cells of rabbits were cultured in de-epith-elialized rat tracheal grafts transplanted to nude mice. At four weeks, human neutrophil elastase (300μg/graft) or saline was injected into the graft lumina. Three weeks later, intratracheal mucus was collected from the retrieved tracheas, and the grafts were examined histologically. The percentage of mucous cells in the elastase-treated tracheas was significantly increased compared to the control level (25.5±0.8% vs. 12.9±0.9%, p