Effects Of Smoking On The Expression Of Inflammatory Factor In Induced Sputum Of Patients With Lower Respiratory Infection

ObjectiveTo investigate the effect of smoking on the expression of inflammatory factors in induced sputum of patients with lower respiratory tract infection(including patients with community acquired pneumonia and acute attack of chronic bronchitis).To compare the effects of smoking on the expressions of IL-4,IL-5 and IFN-gamma in induced sputum of patients with community-acquired pneumonia and chronic bronchitis in acute stage and normal adults(control group).Smoking index can indicate the degree of exposure to tobacco smoke,and explore the relationship between the amount of exposure to smoke and the severity of inflammatory factors.Therefore,by observing the changes of IL-4,IL-5 and IFN-y expression levels in induced sputum of smokers and non-smokers with lower respiratory tract infection and normal subjects,we compared the changes of IL-4,IL-5 and IFN-y expression levels in induced sputum of patients with different smoking index,in order to further explore the effect of smoking on lower respiratory tract infection and clarify the mechanism of smoking on respiratory tract micro ecology,this study took smoking as the main factor to explore the difference of Thl/Th2 cell balance and the expression of related inflammatory factors in order to further explore the role of tobacco in the pathogenesis of lower respiratory tract infection.MethodsFrom January 2017 to March 2018,111 cases of lower respiratory tract infections were admitted to the Department of Respiratory and Critical Care Medicine,Second Affiliated Hospital of Shenyang Medical College.According to the types of diseases,they were divided into 60 cases of community acquired pneumonia(29 smokers,31 non-smokers)and 51 cases of acute attack of chronic bronchitis(23 smokers and 28 non-smokers).The same time was selected in our hospital,42 cases(22 smokers and 20 non-smokers)in the physical examination group.The smoking group with lower respiratory tract infection was divided into mild smoking sub-group(SI<400 sub-group)and severe smoking sub-group(SI)400 sub-group)according to smoking index(branch year).Enzyme-linked immunosorbent assay(ELISA)was used to detect the expression of IL-4,IL-5 and IFN-gamma in induced sputum of selected subjects,and the results were analyzed by data.The difference was statistically significant(P<0.05).Results1.In the community acquired pneumonia group,the expression of IL-4 and IL-5 in sputum induced by smokers was significantly higher than that of non-smokers,and the expression of IFN-gamma was significantly decreased(P<0.001).2.In the acute attack group of chronic bronchitis,the expression levels of IL-4 and IL-5 in sputum induced by smokers were significantly higher than those of non-smokers,and the expression level of IFN-gamma decreased significantly(P<0.001).3.In the health examination group,the expression of IL-4 and IL-5 in sputum induced by smokers was higher than that of non-smokers,and the expression of IFN-gamma decreased(P<0.001).4.In the smoking subgroup of lower respiratory tract infection.the levels of IL-4,IL-5 and IFN-gamma in mild smoking subgroup were higher than those in non-smokers(P<0.001);compared with mild smoking subgroup,the levels of IL-4 and IL-5 in severe smoking subgroup were significantly higher and the levels of IFN-gamma were lower(P<0.001),but both of them were higher than those in non-smokers.Conclusions1.Smoking can be used as an independent factor to affect the expression levels of IFN-gamma and IL-4 and IL-5 in sputum induced by lower respiratory tract infection.Smoking can significantly reduce the level of IFN-gamma in sputum induced by lower respiratory tract patients,while the levels of IL-4 and IL-5 are significantly increased(P<0.001).The imbalance of Thl/Th2 system can cause the occurrence and development of infectious diseases.2.Smokers with lower respiratory tract infections(social acquired pneumonia and acute attack of chronic bronchitis)were divided into mild smoking sub-group(SI<400)and severe smoking sub-group(SI?400)according to the difference of smoking index(branch year).The results showed that the expression of IL-4,IL-5 and IFN-gamma in mild smoking group was higher than that in non-smoking group,and the expression of IFN-gamma in severe smoking group was significantly lower than that in mild smoking group,while the expression of IL-4 and IL-5 was significantly increased.