ABSTRACT
Chronic rhinosinusitis (CRS) is a multifactorial chronic inflammatory disease of the upper airways occurring with or without nasal polyps (NP) that is characterized histologically by the infiltration of inflammatory cells, eosinophils, neutrophils, mast cells, and T cells. Mast cells and basophils are inflammatory cells that are known to play a key role not only in IgE-mediated diseases but also in non-IgEmediated eosinophilic respiratory inflammatory diseases. Mast cells and basophils are increased in nasal and sinus mucosa in chronic rhinosinusitis with and without nasal polyps (CRS with NP and CRS without NP). Basophils are mostly distributed in the surface layer, whereas mast cells are localized in the epithelium as well as the stroma of NP. Furthermore, the majority of degranulated mast cells are localized to the deep stroma of NP. Mast cells in CRS are an important source of a variety of multifunctional cytokines, and mast cells interact with other effector cells and structural cells to induce and upregulate (i.e., amplify) inflammation in CRS. While the properties of mast cells in CRS with NP have been characterized, less is known of the characteristics and role of basophils in CRS. The present review will therefore focus primarily on the studies of mast cells in CRS with NP.
