Investigation Of Autoantibody Profiles In Patients With Chronic Obstructive Pulmonary Disease(COPD) And Healthy Smokers

Objective:The aim of this study is to determine autoantibody profiles of chronic obstructive pulmonary disease(COPD)and healthy smokers,and to investigate the relationship between differentially expressed autoantibodies and COPD.Methods:In this study,we used a protein mircoarray containing nearly 20;000 human proteins to determine the autoantibody profiles of COPD patients and healthy smokers.To validate differentially expressed autoantibodies,we used immunoblotting to detect the expression of anti-lactoferrin IgG with a large number of samples.Furthermore,we determined the correlation of anti-lactoferrin IgG with clinical and immunological phenotypes of the disease.Results:In this study,we identified 575 IgG autoantibodies(263 upregulated and 312 downregulated)that were differentially expressed between COPD patients and healthy smokers.In addition,554 differentially expressed IgM autoantibodies(169 upregulated and 385 downregulated)were identified between the two groups.Further analysis demonstrated that i)Autoantigens of autoantibodies upregulated in COPD patients compared with healthy smokers are enriched in extracellular regions,while those downregulated in COPD patients are enriched in intracellular compartments.ii)IgG autoantibodies against many neutrophil granule proteins were upregulated COPD patients compared with healthy smokers.Furth ermore,we confirmed the upregulation of anti-lactoferrin antibodies in COPD patients compared with healthy controls.However,no significant correlation was observed between anti-lactoferrin autoantibodies and any phenotypes of COPD.Conclusion:In conclusion,in this study we explored an autoantibody profiles of COPD patients and healthy smokers for the first time,which sheds some new light on the pathogenesis of the disease.