Measurement of IgE antibodies to minor components in eosinophilic esophagitis, peanut allergy, and delayed anaphylaxis to mammalian meat

Background In the investigation of food allergy syndromes, serum assays detecting IgE antibodies (Ab) to food allergens use whole extracts on the solid phase, which contain specific allergen components in varying amounts. The interpretation of results assumes that the causative allergen components are adequately represented in the extract and that the presence and level of specific IgE titer to the whole extract of the relevant food(s) are diagnostic of the syndrome. IgE assays for beef or pork can underestimate the IgE Ab to a minor component of mammalian meat, such as galactose-a-1,3-galactose (a-gal). The inciting food allergens in Eosinophilic Esophagitis (EoE) remain unclear, although IgE Ab to milk, wheat, soy, and peanut are frequently present in low titer.