To study the expression of adhesion molecules in epithelial cells from patients with COPD.
The expression of ICAM-1 and HLA-DR in airway epithelial cells from 10 COPD patients, 7 asthmatic patients, 9 chronic bronchitis patients, and 10 healthy volunteers was evaluated using immunohistochemistry techniques. The cells were stained and analysed microscopically.
The percentage of neutrophils in brushing cells from COPD(0.04) were significantly higher than those from asthma(0.01) and normal subjects (0.01). More goblet cells were found in COPD (mean 0.13) and chronic bronchitis (mean 0.11) as compared with asthma (0.03) and healthy volunteers. As to the expression of ICAM-1 in COPD, the percentage of cells expressing ICAM-1(15%) significantly increased in comparison with chronic bronchitis (6.28% P < 0.05), healthy volunteer(1.8%, P < 0.05), and asthma (8.8%, P > 0.05). The score of expression of ICAM-1 in COPD was significantly higher than those in asthma (P < 0.05), chronic bronchitis (P < 0.05) and normal subjects (P < 0.001). As to the expression of HLA-DR in COPD, the percentage of cells expressing HLA-DR(5.9%) significantly increased in comparison with normal subjects (0.6% P < 0.05), but there was no significant difference among COPD, asthma and chronic bronchitis. The score of expression of HLA-DR in COPD was significantly higher than those in healthy volunteers (P < 0.001), chronic bronchitis (P < 0.001) and asthma (P < 0.05). In addition, the percentage of neutrophils in brushing cells from COPD significantly correlated with the expression of ICAM-1 (r = 0.81, P < 0.01).
Upregulation of ICAM-1 in epithelial cell from COPD correlates with the neutrophil infiltration in COPD. Lymphocytes are in an active state in COPD and the use of brush biopsies of the bronchial epithelium may serve as a diagnostic tool for differentiation among COPD, chronic bronchitis and asthma.