IL17A and asthma: Particularly, epithelial STAT3 was identified as a critical regulator of allergen-induced inflammation and AHR in a murine model of asthma[34], IL-17A-induced STAT3 activation led to CCL11/eotaxin-1 production in HASM[21], and PDGF-induced STAT3 mediated the proliferation in HASM cells[8].