Development of type 2-cytokine-mediated eosinophilia and IL-17-mediated neutrophilia during OVA-induced airway inflammation was promoted by intraperitoneal administration of chitin particles (40- to 70-μm in diameter) in the antigen sensitization phase by promoting IL-17 production by macrophages via TLR2 and/or Dectin-19,10,14. This evidence concerns the gene TLR2 and Increased total eosinophil count.