IL5 and chronic rhinosinusitis with nasal polyps: CRSwNP is generally accepted to have a type 2-predominant inflammatory response, with a predominance of eosinophilic inflammation, including eosinophils, mast cells, elevated IgE, and the expression of type 2 cytokines (IL-4, IL-5, IL-9, IL-13, IL-25, and IL-33).