Expression Of Human β-defensin-2 In Induced Sputum Of Patients With Chronic Obstructive Pulmonary Disease

Objective To measure the levels of humanβ-defensin-2 (hBD-2) in the induced sputum of patients with chronic obstructive pulmonary disease(COPD) and investigate the possible role of hBD-2 in the pathogenesis of COPD.Methods 10 samples of induced sputum were collected separately from severe COPD patients, stable COPD patients and healthy subjects. The distinguish of cells in each group of samples was determined by Wright's staining. The levels of hBD-2 in induced sputum were semi-measured by Western blotting analysis, and the concentrations of IL-1βin induced sputum were measured by ELISA . The correlation between the concentrations of IL-1βand the levels of hBD-2 in induced sputum was analyzed.Results The rate of neutrophilic granulocyte in induced sputum from severe COPD patients and stable COPD patients was significantly higher than that of those healthy subjects(P<0.01). The value of hue of hBD-2 in induced sputum by Western blotting analysis from stable COPD patients were significantly lower compared to those healthy subjects(P<0.001), and the value of hue of hBD-2 in induced sputum from severe COPD patients were also significantly lower than those stable COPD patients(P<0.01). The concentrations of IL-1βin induced sputum from stable COPD patients were significantly elevated compared to healthy subject(sP<0.001), while the concentrations of IL-1βin induced sputum from severe COPD patients were also significantly higher than those in stable condition(P<0.01). In induced sputum the rate of neutrophilic granulocyte is positively correlated with the concentrations of IL-1β(r=0.928, P<0.01). The value of hue of hBD-2 in induced sputum in each group by Western blotting analysis is negatively correlated with the concentrations of IL-1β, (r=-0.953, P<0.01 in severe COPD patients group; r=-0.963, P<0.01 in stable COPD patients group; r=-0.886, P<0.01 in healthy subjects group), which means the concentrations of hBD-2 in induced sputum in each group is positively correlated with the concentrations of IL-1β.Conclusion hBD-2 may play a role in the inflammatory process of COPD, and the role possibly has some relationship with IL-1β. But the concrete causality needs to be study.