Expression Pattern of HMGB1 Differs Between Eosinophilic Chronic Rhinosinusitis With Nasal Polyp and Non-Eosinophilic Chronic Rhinosinusitis With Nasal Polyp: A Preliminary Study

Abstract

Background: Eosinophilic chronic rhinosinusitis with nasal polyps (ECRSwNP) is histologically distinct from non-eosinophilic CRSwNP (NECRSwNP) and exhibits a high frequency of recurrence. The differences between the pathogenesis of ECRSwNP and NECRSwNP are not well-characterized. HMGB1 has been implicated in the pathogenesis of CRSwNPs; however, its precise contributions to ECRSwNP and NECRSwNP have not been established. Objective: We evaluated the role of HMGB1 in the pathogenesis of ECRSwNP. Methods: A total of 26 nasal polyps (NPs) from patients with ECRSwNP and NECRSwNP who underwent endoscopic sinus surgery were obtained. Western blotting and immunohistochemistry were performed to compare the HMGB1 levels between the NPs from ECRS and NECRS. A multiplex cytokine assay was performed to evaluate the levels of other cytokines and chemokines in exudates in the NPs. Nasal lavage fluids were used to evaluate extracellular HMGB1 levels using enzyme-linked immunosorbent assay. Results: HMGB1 expression in the NPs was higher in ECRSwNP than in NECRSwNP. The level of HMGB1 in the exudate within the NPs was significantly higher in ECRSwNP than in NECRSwNP. Furthermore, HMGB1 levels in nasal lavage fluids from ECRSwNP were higher than those from NECRSwNP. We found that HMGB1 levels in the exudate in NPs and in nasal lavage fluids effectively differentiate ECRSwNP from NECRSwNP. Conclusion: Our results suggest that a high level of HMGB1 in NPs is an important factor for differentiating ECRSwNP from NECRSwNP. HMGB1 may play a role in the development of ECRSwNP and should be further evaluated.