IGHE and allergic disease: Allergenicity can refer to the ability of an antigen to elicit the production of specific IgE (sIgE), bind to sIgE antibodies, induce cross-linking of sIgE bound to the high affinity receptor, FcεR1, for IgE (IgE/FcεR1complexes) and trigger cell degranulation that may ultimately lead to an allergic reaction in a sensitized subject (2, 3).