Simultaneous analysis of sputum and serum biomarkers in adult asthma

Introduction: To investigate a role of sputum and serum biomarkers in the diagnosis and treatment of chronic asthma, sputum and serum were simultaneously collected from 200 patients and analyzed in respect to possible correlation with several clinical markers. Methods: Two hundred asthma patients were enrolled from the National Hospital Organization Allergy Group Hospitals. Sputum and serum were simultaneously collected. Twenty five serum proteins including cytokines, chemokines, etc. were assayed and analyzed in respect to possible correlation with several clinical markers. As to sputum microbiome analysis, 16S rDNA was analyzed by amplifying 466 bp fragment of V3-V4 region, and fungal ITS was analyzed by amplifying 307 bp fragment of ITS1region. Written informed consent was obtained from every patient. The study was approved by the Central Ethics Committee of National Hospital Organization and performed in accordance with local regulations. Results: Atopic asthma was associated with IL-4, IL-5, and IL-8. Childhood onset of asthma was associated with IL-4 and total IgE. Comorbidity with atopic diseases was associated with IL-4 and eotaxin. Sputum eosinophilia was associated with TARC, IL-5, etc. Uncontrolled asthma was associated with IL-17A, TNF-alpha, and peripheral blood eosinophil numbers. Alpha- and beta-diversity of the sputum were not significantly different among severity and sputum eosinophil groups. Several species were identified significantly different for severe and eosinophilic asthma. Conclusion: Upon comprehensive analysis of serum and sputum biomarkers, several factors were significantly associated with severity and eosinophilic status of the sputum.