IGHE and asthma: Upon re-exposure to the same allergen, antigen can crosslink IgE bound to the FcεR1 on the surface of mast cells and basophils, triggering their degranulation and the release of histamine, lipid mediators (prostaglandin D2, cysteinyl leukotrienes) and pro-inflammatory factors that lead to the clinical symptoms of asthma and rhinitis (Kimber and Dearman, 1997; Fanning and Boyce, 2013).