Detection of Interleukin and Differential Cell Counts in Induced Sputum from Patients with Stable Chronic Obstructive Pulmonary Disease

Objective: to evaluate the role of interleukin, especially of interleukin-8 and neutrophils in development of airway inflammation in chronic obstructive pulmonary disease (COPD). Methods: to measure the concentration of interleukin-1β(IL-1β), interleukin-6(IL-6), interleukin-8(IL-8), tumor necrosis factor-α(TNF-α), differential cell counts and the percentage predicted of forced expiratory volume in 1 second (FEV1% predicted) in induced sputum from 30 normal control subjects and 60 COPD respectively and to compare the significance and relativity of the parameter in two groups. Results: the sputum from normal subjects contained a significantly higher proportion of macrophages(55 5±3 6%,P0 05), the sputum from COPD patients contained a significantly higher proportion of neutrophils (61 7±1 9%,P0 01). The sputum concentration of IL-1β, IL-6, IL-8, TNF-αwere significantly higher in the patients with COPD than in the control subjects (P0 001 respectively), IL-8 was higher by far ( q =8.544, P0 01). The sputum concentration of IL-8 in the patients with COPD was significantly correlated with the neutrophils ( r =0 88, P0 001), the sputum concentration of IL-8 was negatively correlated with FEV1% predicted ( r =-0 90, P0 001). Conclusions: induced sputum was the character of airway inflammation in the patients with stable COPD, which is a factor affecting the effect of treatment.