Human airway trypsin-like protease induces mucin5AC hypersecretion via a protease-activated receptor 2-mediated pathway in human airway epithelial cells

► MUC5AC is the major secreted mucin in inflammatory airway diseases. ► HAT is isolated from the sputum of patients with chronic airway diseases. ► HAT is a serine protease and an agonist of the PAR2 receptor. ► HAT can induce MUC5AC hypersecretion in human airway epithelial cells. ► The PAR2-mediated pathway is involved in HAT-induced MUC5AC hypersecretion.