Neutrophils in nasal polyps exhibit transcriptional adaptation and proinflammatory role depend on local polyp milieu.

Abstract

Chronic rhinosinusitis with nasal polyps (CRSwNP) is an inflammatory upper airway disease, divided into eosinophilic CRSwNP (eCRSwNP) and noneosinophilic CRSwNP (neCRSwNP) according to eosinophilic levels. Neutrophils are major effector cells in CRSwNP. but their role in different inflammatory environments remain largely unclear. We performed an integrated transcriptome analysis of polyp-infiltrating neutrophils from CRSwNP patients, using healthy donor blood as a control. Flow cytometry and in vitro studies showed that neutrophils are activated in both CRSwNP type. The scRNA-sequencing analysis demonstrated that neutrophils were classified into five functional subsets, with GBP5+ neutrophils occurring mainly in neCRSwNPs and a high proportion of CXCL8+ neutrophils in both subendotypes. GBP5+ neutrophils exhibited significant IFN-I pathway activity in neCRSwNPs. CXCL8+ neutrophils displayed increased neutrophil activation scores and mainly secrete Oncostatin M (OSM), which facilitates communication with other cells. In vitro experiments revealed that OSM could enhance IL-13- or IL-17-mediated immune responses in nasal epithelial cells and fibroblasts. Our findings revealed that neutrophils exhibited transcriptional plasticity and activation when exposed to polyp tissue and exert their proinflammatory role in the pathogenesis of CRSwNP by releasing OSM to interact with epithelial cells and fibroblasts in a manner dependent on the inflammatory milieu.