PT  - JOURNAL ARTICLE
AU  - K Sakai
AU  - T Kohri
AU  - M Tashiro
AU  - Y Kishino
AU  - H Kido
TI  - Sendai virus infection changes the subcellular localization of tryptase Clara in rat bronchiolar epithelial cells
AID  - 10.1183/09031936.94.07040686
DP  - 1994 Apr 01
TA  - European Respiratory Journal
PG  - 686--692
VI  - 7
IP  - 4
4099  - http://erj.ersjournals.com/content/7/4/686.short
4100  - http://erj.ersjournals.com/content/7/4/686.full
SO  - Eur Respir J1994 Apr 01; 7
AB  - Tryptase Clara activates the infectivity of Sendai and influenza viruses proteolytically. In this study, we investigated changes in the subcellular localization of tryptase Clara in rat bronchioles with progression of Sendai virus infection. Tryptase Clara and Sendai virus F2 antigen were localized by light and electron immunohistochemical studies. In the uninfected rat lung, tryptase Clara was specifically localized in the secretory granules of respiratory bronchiolar epithelial nonciliated cells, but not in bronchiolar ciliated, or alveolar cells. In the initial stage of Sendai virus infection with slight pathological changes, however, anti-tryptase Clara was highly reactive in luminal peripheral membranes of both nonciliated and ciliated epithelial cells of the bronchioles together with some Sendai virus envelope glycoprotein, F2 antigen. In the progressed stage, tryptase Clara was hard to detect, with heavy accumulation of F2 antigen in the epithelial cells. These immunohistochemical results support our previous findings that in the bronchial lavage fluid tryptase Clara is significantly increased both in amount and activity after viral infection. These results suggest that Sendai virus stimulates the secretion of tryptase Clara from nonciliated bronchiolar epithelial cells to the airway lumen. Accumulation of tryptase Clara on the luminal surface of the bronchiolar epithelial cells and/or in the airway lumen may produce favourable conditions for proteolytic viral activation and multiplication.