SEVERITY OF AIR-FLOW LIMITATION IS ASSOCIATED WITH SEVERITY OF AIRWAYINFLAMMATION IN SMOKERS

To investigate the relationship between airflow limitation and airway inflammation in smokers, we examined paraffin-embedded bronchial biops ies obtained from 30 smokers: 10 with severe airflow limitation, eight with mild/moderate airflow limitation, and 12 control smokers with no rmal lung function. Histochemical and immunohistochemical methods were performed to assess the number of inflammatory cells in the subepithe lium and the expression of CC chemokines macrophage inflammatory prote in (MIP)-1 alpha and -1 beta in the bronchial mucosa. Compared with co ntrol smokers, smokers with severe airflow limitation had an increased number of neutrophils (p < 0.02), macrophages (p < 0.03), and NK lymp hocytes (p < 0.03) in the subepithelium, and an increased number of MI P-1 alpha+ epithelial cells (p < 0.02). When all smokers were consider ed together, the value of FEV, was inversely correlated with the numbe r of neutrophils (r = -0.59, p < 0.002), macrophages (r = -047, p < 0. 012), NK-lymphocytes (r = -0.51, p < 0.006) in the subepithelium, and with the number of MIP-1 alpha+ epithelial cells (r = -0.61, p < 0.003 ). We conclude that in smokers the severity of airflow limitation is c orrelated with the severity of airway inflammation and that severe air flow limitation is associated with an increased number of neutrophils, macrophages, NK lymphocytes, and MIP-1 alpha+ cells in the bronchial mucosa.