The Expression And Significance Of IL-33 Protein In Lung Tissue Of Patients With Chronic Obstructive Pulmonary Disease

Objective: To observe the expression of IL-33 protein in lung tissue of patients with COPD and investigate the role of IL-33 in the airway inflammation of COPD and how smoking impacts the expression of IL-33 protein compared with population of normal lung function.Methods: A total of 19 subjects were nonsmokers with normal lung function(NS group), 18 subjects were smokers with normal lung function(S group) and 22 subjects were smokers with COPD(COPD group). The histological features of three groups by hematoxylin-eosin staining, and the immune-histochemical methods were used to evaluate IL-33 protein expression in lung tissue.Results:(1)The IL-33 protein levels in lung tissue of three groups: NS group(17056.018±16311.914)、S group(79130.631±43435.497)、COPD group(311231.188±170591.013).The IL-33 protein levels were significantly increased in COPD group compared with NS group and S group(both P<0.01),the difference was statistically significant;the IL-33 protein levels of S group is higher than NS group, but the difference between NS group and S group was insignificant(P>0.05).(2)There was a positive correlation between the IL-33 protein levels of S group and the smoking index(branch-yrs),r = 0. 694(P<0.01);the IL-33 protein levels of S group with FEV1%pred was negatively correlated, r =-0. 520(P<0.05);the IL-33 protein levels of S group with and FEV1/FVC(%) was negatively correlated, r =-0.508(P<0.05). There was a positive correlation between the IL-33 protein levels of COPD group and the smoking index(branch-yrs),r = 0. 647(P<0.01);the IL-33 protein levels of COPD group with FEV1%pred was negatively correlated, r =-0. 503(P<0.05);the IL-33 protein levels of COPD group with and FEV1/FVC(%) was negatively correlated, r =-0.501(P<0.05).Conclusions:1. The IL-33 protein levels are significantly increased in in lung tissue of COPD patients compared with smokers and nonsmokers with normal lung function; the difference between the IL-33 protein levels of nonsmokers with normal lung function and smokers with normal lung function is insignificant. 2. There are positive correlation between the IL-33 protein levels of COPD patients compared and smokers with normal lung function and the smoking index(branch-yrs); the IL-33 protein levels with FEV1%pred and FEV1/FVC(%) are negatively correlated.