IL13 and asthma: The Th2 cell cytokines (IL-5) recruit eosinophils and activate them; IL-13 is secreted to induce goblet cell hyperplasia and mucous hypersecretion in airway epithelial cells [36], causing the typical histological features of asthma, including epithelial shedding, goblet cell hyperplasia, subepithelial fibrosis, thickened airway, smooth muscle mass, and inflammatory cell infiltration [37].