Adult allergic rhinitis sufferers have unique nasal mucosal and peripheral blood immune gene expression profiles: A case-control study

Background: Allergic rhinitis (AR) is a complex disease involving both mucosal and systemic immune compartments. Greater understanding of the immune networks underpinning AR pathophysiology may assist with further refining disease-specific biomarkers. Objective: To compare immune gene expression profiles in nasal mucosa and peripheral blood samples between adults with AR and controls without AR. Methods: This cross-sectional study included 45 adults with moderate-severe and persistent AR (37.6 +/- 12.8 years; mean +/- SD) and 24 adults without AR (36.6 +/- 10.2). Gene expression analysis was performed using the NanoString nCounter PanCancer Immune profiling panel (n = 730 immune genes) in combination with the panel plus probe set (n = 30 allergy-related genes) with purified RNA from peripheral blood and cell lysates prepared from combined nasal lavage and nasal brushing. Results: One hundred and thirteen genes were significantly differentially expressed in peripheral blood samples between groups (p < .05). In contrast, 14 genes were differentially expressed in nasal lysate samples between groups (p < .05). Upregulation of allergy-related genes in nasal mucosa samples in the AR group was observed. Namely, chemokines CCL17 and CCL26 are involved in the chemotaxis of key effector cells and TPSAB1 encodes tryptase, an inflammatory mediator released from activated mast cells and basophils. Six differentially expressed genes (DEGs) were in common between the nasal mucosa and blood samples. In addition, counts of specific DEGs in nasal mucosa samples were positively correlated with eosinophil and dust mite-specific immunoglobulin E (IgE) counts in blood. Conclusions and Clinical Relevance: Distinct gene expression profiles in blood and nasal mucosa samples were observed between AR sufferers and controls. The results of this study also provide evidence for a close interaction between the local site and systemic immunity. The genes identified in this study contribute to the current knowledge of AR pathophysiology and may serve as biomarkers to evaluate the effectiveness of treatment regimens, or as targets for drug discovery.