IGHE and allergic disease: Specifically, COS (1) inhibited the increase in IgE levels induced by HDM exposure; (2) suppressed excessive mucus secretion caused by allergies and prevented airway fibrosis, thereby improving airway resistance; (3) inhibited the infiltration of inflammatory cells into the airways, and (4) suppressed the expression of Th1-type inflammatory cytokines and the activation of the NF-κB pathway in airway epithelial cells and lung tissue (Figure 6).