The effect of melatonin or luzindole on OVA-induced airway inflammation. (A) Protocol of administration of melatonin or luzindole during establishing allergic airway diseases model. (B,C) Protein expression of TLR2 in lung tissues of OVA-challenged WT mice treated with melatonin or not. (D) Lung histopathology based on H&E staining to evaluate inflammatory cell infiltration, arrows indicates infiltrated leukocytes. (E) Mucus secretion was analyzed based on PAS staining, arrow heads indicates goblet cells. (F) Histological scoring of lung inflammation. (G) Quantification of mucus secretion. *p < 0.05, **p < 0.01, ***p < 0.001.