IGHE and allergic disease: Memory allergen-specific Th2 cells activated via IgE-facilitated allergen presentation by DCs and B cells and type 2 innate lymphoid cells (ILC2) activated by epithelial cell–derived alarmins (TSLP, IL-33, and IL-25) produce large amounts of IL-4, IL-5, IL-9, and IL-13 contributing to maintain allergen-specific IgE levels, eosinophilia, mucus production, recruitment of inflammatory cell, and tissue inflammation, which are involved in the chronicity and the most severe clinical manifestations of allergy [2, 25].