Bioinformatics-based screening and experimental validation of biomarkers for the treatment of connective tissue-associated interstitial lung disease with liquorice and dried ginger soup

Biomarkers for CTD-ILD diagnosis, treatment response evaluation, and pathogenesis elucidation are lacking. Licorice-dried ginger soup alleviates lung injury, but its mechanism is unknown. This study aimed to identify biomarkers of this herbal treatment for CTD-ILD. Public datasets of Peripheral blood mononuclear cells (PBMCs) from CTD-ILD (n = 4) and connective tissue disease-associated non-Inflammatory lung disease (CTD-NILD) (n = 3) patients were analyzed using differential expression (p.adj < 0.05 & |log2 Fold Change (FC)| > 0.5), protein-protein interaction networks, and cytohubba algorithms (Top5 genes from six algorithms). Functional enrichment, upstream pathway activity, phosphorylation, molecular regulatory networks, and molecular docking were performed and the expression of biomarkers was validated in clinical samples. Five biomarkers (CXCL8, IL1A, IL1B, NFE2L2, and PTGS2) were identified. Functional analysis linked these pathways to innate immunity, cytokine activity, and pertussis pathways. Regulatory networks have been implicated in toll-like receptors, chemokine signaling, and DNA replication. Biomarkers correlated with lung injury and showed high expression in the blood/immune cells. Molecular docking confirmed strong binding between the biomarkers and quercetin. CXCL8, IL1A, IL1B, NFE2L2, and PTGS2 are critical CTD-ILD biomarkers. Licorice ginger soup may target these genes via quercetin, providing novel diagnostic and therapeutic insights.