Nucleolar silver staining patterns and HLA-DR antigen expression in bronchial epithelial cells in chronic bronchitis

Bronchial epithelial cells obtained by brush biopsy during fiberoptic bronchoscopy performed in 12 patients with chronic bronchitis and 12 healthy control subjects, were investigated for HLA-DR antigen expression and nucleolar silver staining patterns. In all patients with chronic bronchitis the number of bronchial epithelial cells positive to HLA-DR antigen was highly increased (> 90%), whereas in the controls only a few epithelial cells (< 10%) showed a weak HLA-DR antigen expression. Patients with chronic bronchitis showed an increased lymphocytic reaction compared to the control subjects. Both in the patients with chronic bronchitis and in the healthy controls the number of nucleoli was the same. The number of silver stained dots per nucleus was significantly higher in patients with chronic bronchitis than in the control subjects (7.70 +/- 0.87 as against 5.11 +/- 0.52; p < 0.0001). The intensity of the lymphocytic reaction correlated with the HLA-DR antigen expression and the increase in silver staining (Spearman's r = 0.543; p < 0.01). This indicates the influence of inflammation on the activation of epithelial cells derived from the respiratory tract.