TSLP and allergic asthma: Allergic asthma is triggered by allergens, pollutants, and microorganisms, which are captured by dendritic cells (DCs) and drive bronchial epithelial cells (BECs) to release IL-25, IL-33, and thymic stromal lymphopoietin (TSLP), which in turn activate group 2 innate lymphoid cells (ILC2) in the bronchial mucosa [18].