CD8+ve cells in the lungs of smokers with chronic obstructive pulmonary disease

Previous studies have shown an increased number of inflammatory cells and, in particular, CD8+ve cells in the airways of smokers with chronic obstruct ive pulmonary disease (COPD). In this study we investigated whether a simil ar inflammatory process is also present in the lungs, and particularly in l ung parenchyma and pulmonary arteries. We examined surgical specimens from three groups of subjects undergoing lung resection for localized pulmonary lesions: nonsmokers (n = 8), asymptomatic smokers with normal lung function (n = 6), and smokers with COPD (n = 10). Alveolar walls and pulmonary arte ries were examined with immunohistochemical methods to identify neutrophils , eosinophils, mast cells, macrophages, and CD4+ve and CD8+ve cells. Smoker s with COPD had an increased number of CD8+ve cells in both lung parenchyma (p < 0.05) and pulmonary arteries (p < 0.001) as compared with nonsmokers. CD8+ve cells were also increased in pulmonary arteries of smokers with COP D as compared with smokers with normal lung function (p < 0.01). Other infl ammatory cells were no different among the three groups. The number of CD8ve cells in both lung parenchyma and pulmonary arteries was significantly c orrelated with the degree of airflow limitation in smokers. These results s how that an inflammatory process similar to that present in the conducting airways is also present in lung parenchyma and pulmonary arteries of smoker s with COPD.