Abstract
CC-chemokines are chemotactic factors expressed in a wide range of cell types and tissues. The aim of this study was to evaluate the involvement of CC-chemokines in the airways inflammation of patients affected by chronic bronchitis. The study evaluated, with an immunoassay, the concentrations of monocyte chemotactic protein-1 (MCP-1), macrophage inflammatory protein-1alpha (MIP-1alpha) and macrophage inflammatory protein-1beta (MIP-1beta), in the bronchoalveolar lavage fluid (BALF) of 12 smokers affected by chronic bronchitis and 14 smoking, 15 nonsmoking and six exsmoking healthy subjects. MCP-1 was significantly increased in patients with chronic bronchitis ((mean+/-SD) 10.75+/-4.04 pg x mL(-1)) and in the smoker control group (12.39+/-5.87 pg x mL(-1)) compared with healthy exsmokers: (7.12+/-1.60 pg x mL(-1), p=0.035 and p=0.045, respectively) and nonsmokers (6.41+/-3.87 pg x mL(-1), p=0.003 and p=0.006, respectively). MIP-1alpha concentrations were undetectable. A significant difference was observed in MIP-1-beta levels in BALF of chronic bronchitics (8.11+/-5.97 pg x mL(-1)) compared to smoker (3.57+/-2.90 pg x mL(-1), p=0.018), exsmoker (3.43+/-0.68 pg x mL(-1), p=0.025) and nonsmoker (3.39+/-3.73 pg x mL(-1), p=0.008) control groups. A negative correlation was observed between MIP-1beta levels and forced expiratory volume in one second values (p=-0.64, p=0.035) in chronic bronchitics. An increase of monocyte chemotactic protein-1 is related to smoking habit and seems consistent with a lung inflammatory reaction. On the contrary, an increase in macrophage inflammatory protein-1beta levels is restricted to smokers developing chronic obstructive pulmonary disease. These data suggest a role of CC-chemokines in the pathogenesis of chronic bronchitis.