IL17A and asthma: Danlong Dingchuan Decoction can also decrease TGF-β1 expression, decrease IL-17 secretion, and reduce airway inflammation, which is consistent with the expected hypothesis that the mechanism of Danlong Dingchuan Decoction in treating asthma includes alleviating airway inflammation, reducing the expression of Th2 cytokines, affecting the balance of Th1/Th2 cells, and thus inhibiting Th2-mediated asthma.