Relationship between Interleukin-13 in Plasma and Induced Sputum in Chronic Obstructive Pulmonary Disease

Objective To study changes in levels of IL-13 in induced sputum and plasma in patients with chronic obstructive pulmonary disease(COPD).Methods Levels of IL-13 in induced sputum and plasma and pulmonary functionwere examined for patients with COPD during acute exacerbation and stable stage.Healthy volunteers were included as controls.Results Levels of IL-13 in patients with COPD in induced sputum and plasma were significantly higher than those in healthy controls(P0.01).The concentrations of IL-13 in patients with COPD during acute exacerbation were significantly higher than those during stable stage(P0.01).The 1evels of IL-13 in plasma was not correlated with their pulmonary function(P0.01),but the levels of IL-13 in induced sputum was negatively correlated with their pulmonary function(P0.01).Conclusion The levels of IL-13 in induced sputum and plasma of patients with COPD increase,which may be related with the pathogenesis and exacerbation of COPD.Local inflammatory reactions,rather than systematic one,seem to be closely related to airflow limitation in patients with COPD.