Periostin as a marker of mucosal remodelling in chronic rhinosinusitis

Background: Although extracellular matrix (ECM) proteins are associated with irreversible lower airway changes, the relationship with upper airway remodelling which occurs during chronic rhinosinusitis (CRS) is poorly understood. This study assessed the expression of ECM proteins periostin, fibulin-1, fibronectin and collagenIV in nasal mucosa of patients with and without histologic features of remodelling.

Methods: A cross-sectional study of sinonasal mucosal biopsies taken from patients, undergoing surgery for CRS was performed, where patients were grouped according to remodelling, defined by basement membrane thickening (BMT>7.5µm) and subepithelial fibrosis. An overall view and three random fields of immunostained tissue sections that included epithelium, basement membrane and submucosa, were imaged using Zeiss Zen software. The area and intensity of positive staining were scored by two blinded observers, using a 12-point ordinal scale of weak to strong.

Results: 65 patients (47.6 ± 13.4years, 44.6% female) were assessed. Patients were grouped as controls 26.2%, BMT/no fibrosis 38.5% or BMT and fibrosis 33.8%. Stronger grade of periostin expression was associated with remodelling changes and tissue eosinophilia>10/HPF. Fibulin-1, fibronectin and collagenIV did not differ.

Conclusion: Periostin expression was associated with the presence of BMT, fibrosis and tissue eosinophilia; and may identify patients undergoing remodelling changes.