IL5 and Nasal polyposis: On the other hand, the predominant inflammatory state in chronic rhinosinusitis with nasal polyps (CRSwNP) is Th2 inflammation, in which increased production of Th2 cytokines and chemokines such as IL4, IL5, IL13, eotaxin1 (CCL11), eotaxin2 (CCL24), and eotaxin3 (CCL26), as well as infiltration of significant numbers of mast cells, eosinophils, and probably neutrophils, are expected [5, 6].