[Role of bronchial epithelial cells in chronic obstructive pulmonary disease].

Chronic obstructive pulmonary disease (COPD) is characterized by increased numbers of neutrophils in the airway lumen and increased infiltration of CD8 positive T lymphocytes both in the airways and in the lung parenchyma. However, the underlying reasons for these changes have not been fully investigated. Differences in bronchoepithelial activation in COPD patients may contribute to COPD pathophysiology since the bronchial epithelium does not act as a passive barrier but has the potential to orchestrate local inflammatory reactions by releasing a variety of inflammatory mediators. The expressions of several CXC and CC chemokines were studied in primary bronchial epithelial cells derived from COPD patients and smokers without airflow limitation. In addition, cDNA array technology was used to investigate the differential bronchoepithelial expression of cytokine and cytokine-related genes in COPD patients and lifelong non-smokers without airflow obstruction. Bronchial epithelial cells from COPD patients are characterized by increased expressions of CXC chemokines but not CC chemokines. In addition, CD 146 was identified as a new adhesion molecule showing significant upregulation in primary bronchial epithelial cells derived from COPD patients, on both the steady-state mRNA and protein level. These results suggest that the bronchial epithelium plays an important role in COPD pathophysiology.