Expression And Significance Of Serum IL-17 And TLR4 In Patients With Chronic Obstructive Pulmonary Disease

Objective:Chronic obstructive pulmonary disease,COPD for short,is a kind of respiratory disease with high morbidity,high disability and high fatality rate,and it is very harmful to one's health.At present,the exact pathogenesis of COPD has not been fully clarified,the researchers generally believe that the airway and pulmonary parenchyma chronic inflammation are the most important pathogenesis of COPD,and inflammation can involve the whole body of patient.In recent years,inflammatory immune factors have become a focus of research on the pathogenesis of COPD.Interleukin-17(IL-17)is a powerful precursor inflammatory factor that mediates the inflammatory response while also participating in an acquired immune response.Current studies at home and abroad show that IL-17 is closely related to the occurrence and development of respiratory diseases,cardiovascular diseases,immune system diseases,rheumatic diseases,tumors,acute and chronic inflammation and other diseases.Toll-like receptor 4(TLR4)is a natural immunological recognition receptor originally found in Drosophila embryos,it initiates a natural immune response by recognizing the pathogenic molecule,and mediates inflammatory reaction through its signaling pathway.Current research shows that TLR4 is involved in the pathogenesis of pneumonia,sepsis,kidney disease,systemic lupus erythematosus,cancer and many other diseases.Through comparing the difference in serum IL-17,TLR4 expression level and pulmonary function index between COPD patients in stable phase and healthy smokers and healthy non-smokers,this paper analyzed the correlation between serum IL-17,TLR4 level and airflow limitation,symptom evaluation index of COPD patients,and discussed the role of serum IL-17 and TLR4 in the pathogenesis of inflammatory immunity in patients with chronic obstructive pulmonary disease,hoping to provide a new theoretical idea for the treatment of COPD and find a new target spot.Methods:60 patients with stable COPD(COPD Group)who were admitted to the respiratory medicine department of Chengde Central Hospital from Dec,2016 to Dec,2017 and 45 smokers(healthy smoking group)and 45 non-smokers(healthy non-smoking group)who underwent a physical examination in the same hospital during the same period were selected as the object of study,their sex,age,height,weight,smoking index and other information were recorded.All of the three groups of subject underwent a pulmonary function test,then their elbow median venous blood was drawn and retained as a sample for the measurement of level of serum IL-17 and TLR4 with the method of enzyme-linked immuno sorbent assay(ELISA).All the smoking patients with stable COPD were investigated with modified British medical research council(mMRC)and COPD Assessment Test(CAT).SPSS19.0 statistical software was used to process and analyze the data.One-way analysis of variance was used to compare the level of serum IL-17 and TLR4 of the subjects in the three groups,pairwise inter-group comparison was done by LSD-t test.The correlation between serum IL-17 and TLR4 and pulmonary function index,mMRC grading,CAT score,age,body mass index and smoking index was evaluated with Pearson correlation analysis;the correlation between serum IL-17 and level of expression of TLR4 was evaluated with Pearson correlation analysis.The difference is deemed as statistically significant when P<0.05.Results:1.general information(data)There were no statistically significant differences in age,sex composition and body mass index(BMI)(P>0.05)between the three groups of subjects.The smoking stable COPD Group was lower than the healthy Smoking group and the healthy Non-smoking group in pulmonary function index FEV1/FVC and FEV1%pred,the differences were all statistically significant(P<0.05);There was no statistically significant difference in FEV1/FVC and FEV1%pred between healthy smoking group and healthy Non-Smoking group(p>0.05).2.Serum Serum IL-17 and level of TLR4 of subjects in each groupThe level of serum IL-17 of COPD group was higher than that of the healthy smoking group and healthy non-smoking group,the healthy smoking group was higher than the healthy non smoking group,and there were statistically significant differences between all groups(p<0.05).The level of serum TLR4 in COPD group was higher than that in healthy smoking group and healthy non-smoking group,while the healthy non-smoking group was higher than the healthy smoking group,there were statistically significant differences between all groups(p<0.05).3.Correlation between serum IL-17,TLR4 level and FEV1pred%The level of serum IL-17 in COPD group was negatively correlated with the FEV1%pred(r=-0.717,p<0.05),and the level of serum TLR4 in COPD group was negatively correlated with FEV1%pred(r=-0.623,p<0.05).As to the healthy smoking group and healthy non-smoking group,there was no significant correlation between the level of serum IL-17,TLR4 level and the level of FEV1%pred(p>0.05).4.Correlation between serum IL-17,TLR4 level and mMRC grading,CAT score,age,BMI and smoking indexThe level of serum IL-17 in COPD group was positively correlated with the mMRC grading(r=0.367,P<0.05),positively correlated with CAT score(r=0.687,P<0.05),and insignificantly correlated with age,BMI and smoking index(P>0.05).the level of serum TLR4 in COPD group was positively correlated with the mMRC grading(r=0.326,P<0.05),positively correlated with CAT score(r=0.589,P<0.05)and insignificantly correlated with age,BMI and smoking index(P>0.05).5.Correlation between serum IL-17 and TLR4Serum IL-17 was positively correlated with TLR4 level in COPD group(r=0.731,P<0.05);as to the healthy smoking group and healthy non-smoking group,there was no significant correlation between serum IL-17 and TLR4 level(r=-0.263,P>0.05;r=-0.026,P>0.05).Conclusions:1.The level of serum IL-17 in COPD patients is significantly higher than that in the healthy population,the level of serum IL-17 is higher in the healthy smokers than in the healthy non-smokers,suggesting tha t,IL-17 not only plays an important role in the pathogenesis of COPD inflammation,but also participates in the process of systemic inflammato ry reaction caused by smoking.2.The level of serum TLR4 in COPD patients is significantly high er than that in the healthy population,the level of serum TLR4 is high er in the healthy non-smokers than in the healthy smokers,suggesting t hat,Serum TLR4 is involved in the pathogenesis of COPD and meanti me it is indicated that the innate immune function of smoker has decre ased.3.The serum IL-17 and TLR4 level in COPD patients are both ne gatively correlated with the FEV1%pred,suggesting that,serum IL-17 and TLR4 level may be related to the airflow limitation and severity of disease of patients.4.The expression level of both IL-17 and TLR4 in serum of COPD patients is positively correlated with mMRC grading and CAT score,w hich indicates that,the level of IL-17 and TLR4 in serum could be cor related with the severity of dyspnea and the living quality of patients w ith COPD.5.The level of serum IL-17 is positively correlated with the level o f TLR4 in patients with COPD,which indicates that,the degree of infl ammation in COPD patients may be related to the degree of immune re sponse,and blocking inflammatory immune response may provide a newway for the prevention and treatment of COPD.