Potential biomarkers of idiopathic pulmonary fibrosis discovered in serum by proteomic array analysis

Idiopathic pulmonary fibrosis (IPF) is a serious interstitial pneumonia leading to considerable morbidity and mortality. The unavailability of prompt biomarkers for IPF has hampered our ability to uncover preventive and therapeutic measures for this disease in a well-timed manner. The objective of this study was to identify valuable IPF associated blood biomarkers for stratifying patients and predicting outcome. By analyzing the expression of proteins in sera of 50 IPF patients and 10 healthy individuals using Biotin Label-based Antibody Array, we identified a signature of 46 differentially expressed proteins including 15 up-regulated and 31 down-regulated proteins as potential IPF biomarkers. The PPI network showed strong and complex interactions between identified biomarkers while functional enrichment analysis revealed their implications in 589 biological processes and 40 KEGG metabolic pathways. Western blotting and RT-PCR validation results corroborated with the microarray data. Our research unearthed candidate biomarkers with great potential for diagnosis of IPF and suggested that recombinant thrombopoietin and anti-CCL18 antibodies, as well as other identified biomarkers may represent a novel advance in the medical treatment of patients with IPF.