Fig. 1

Overview of the experimental design and the number of samples for proteomics, metabolomics, and protein validation. 40 stable advanced COPD along side 40 controls were recruited, then applied proteomics and metabolomics techniques to detect potential biomarkers. An additional 30 COPD vs 30 controls was used to validate the resultant proteomic signatures. Molecular subtyping performed using proteomics data. Receiver operating characteristics (ROC) analyses used to evaluate predictive capability of the biomarkers, and then experimentally validated the predictions on mild-to-moderate COPD