Study on cell-to-cell interactions between airway epithelial cells and inflammatory cells in the pathogenesis of asthma

点击翻译按钮获取中文摘要

Bronchial asthma is characterized by profound bronchoconstriction and persistent airway inflammation associated with hyperresponsiveness. There is a dense accumulation of eosinophils, mast cells and lymphocytes, whcih are belived to play important roles in the pathogenesis of asthma. We investigated the cell-to-cell interactions, especially between airway epithelial cells and the inflammatory cells in vitro. Airway epithelial cell-derived fibronectin, IL-8 and RANTES showed a chemotactic activity for mast cells, Iymphocytes and eosinophils, respectively. Airway epithelial cells also express and release IL-6 and GM-CSF which activate lymphocytes and eosinophils, and epithelium-derived endothelin-lshowed a potent bronchoconstricting action on airway smooth muscles.We further showed that eosinophil adhesion to bronchial epithelial cells is one of the important signals for eosinophil activation and degranulation.Airway epithelial cell growth and differentiation are crucial steps for the repair processes of airway mucosa, and failure of correct repair may result in tissue remodeling. We demonstrated that both eosinophils and epithelial cells express TGFbeta, whcih may be a factor to suppress normal repair and to induce remodeling in the airways. We believe our findings gave new insights into the cell-to-cell interactions important in the thogenesis of asthma, and may help develop better strategies for the treatment of this disease.