Expression of the epithelial polymeric immunoglobulin receptor is decreased in allergic rhinitis and eosinophilic rhinosinusitis

Background Transcytosis of immunoglobulin A (IgA) through polarized bronchial and sinonasal epithelial cells is mediated by the polymeric immunoglobulin receptor (pIgR), which represents the rate-limiting factor for this frontline protective mechanism in the airways. pIgR expression is decreased in COPD, lung cancer and nasopharyngeal carcinoma, while its role in sinonasal chronic inflammatory diseases has not been explored. The aim of this study was thus to assess pIgR expression in sinonasal mucosa of patient with chronic rhinosinusitis with (CRSwNP) or without polyps (CRSsNP) and in allergic rhinitis (AR), as well as IgA and SC (the released soluble part of the pIgR) in nasal secretions.