Upregulation of adhesion molecules in the bronchial mucosa of subjects with chronic obstructive bronchitis.

Abstract

To determine whether adhesion molecules and cytokines are upregulated in the bronchial mucosa of chronic bronchitics, we obtained bronchial biopsies in 16 chronic bronchitics, in eight asymptomatic smokers, and in seven normal nonsmoking subjects. Bronchial biopsies were examined by immunohistochemistry to identify the expression of E-selectin and intercellular adhesion molecular-1 (ICAM-1) on vessels and on bronchial epithelium, and the expression of interleukin-1 beta (IL-1 beta), tumor necrosis factor-alpha (TNF-alpha), neutrophil elastase, and eosinophil cationic protein (EG-2) on cells in the submucosa. Chronic bronchitics had an increased number of E-selectin-positive vessels when compared with both asymptomatic smokers (p < 0.05) and normal subjects (p < 0.01). The numbers of ICAM-1-positive vessels, neutrophils, and IL-1 beta, TNF-alpha-, and EG-2-positive cells were not significantly different in the three groups of subjects examined. When the bronchitic group was divided according to the presence or absence of airway obstruction, the increased number of E-selectin-positive vessels persisted only in bronchitics with airway obstruction, who also had an increased expression of ICAM-1 on basal epithelial cells. We concluded that in the bronchial mucosa of chronic bronchitics with airway obstruction, there is an increased expression of E-selectin on vessels and of ICAM-1 on basal epithelial cells, suggesting the involvement of these adhesion molecules in the pathogenesis of the disease.