Advancing Non-Invasive Respiratory Diagnostics: Multiplex Nasal Biomarker Profiling for Stratification of Airway Inflammatory Diseases

This study explores the potential of nasal secretions to serve as a source of biomarkers for diagnosing respiratory conditions. A total of 40 inflammatory biomarkers were detected and quantified in participants with upper respiratory diseases, including chronic rhinosinusitis (CRS), allergic rhinitis, and viral and bacterial infections. The different expression levels of various biomarkers could distinguish CRS participants with and without nasal polyps (i.e. CRP, GzmB, IL-4, MMP-1, MMP-8, SAA and TREM-1), and healthy and rhinitis participants (i.e. CRP, EGF, Eotaxin-1, Fractalkine, IL-1RA, IL-5, IP-10 and TRAIL). CRP, G-CSF, GzmA, IL-1, IL-2, IL-5, IL-8, IL-9, MMP-1, TNFa and TREM-1 protein expression differed between the healthy, viral and bacterial-infected individuals, and EGF, G-CSF, MCP-1, MIP1a and MIP-1b protein expression differed between type 2 and non-type 2 inflammatory cohorts. Significant correlations were also noted between SNOT-22 scores and specific cytokines, such as IP-10 and TRAIL. Despite the heterogeneity of patient diagnoses, these findings highlight the potential of nasal fluid as a readily accessible reflection of respiratory health. Future studies with larger cohorts and standardized methodologies are needed to validate these biomarkers and potentially enable precision diagnosis and improved treatment of respiratory conditions.