Contrast between immunologic and nutritional properties of food proteins

Bioanalytical characterization of proteins

Allergens from the view of a protein chemist are quite normal proteins, not to distinguish from non allergenic proteins. The first task is therefore to recognize and identify the proteins responsible for the allergenic reaction. This is usually only possible if the allergenic structure is conserved during the purification procedures. For a detailed analysis of the allergenic protein modern protein chemical methods for characterization, identification, determination of posttranslational modifications and epitope characterization have to be applied. Such techniques are briefly described in this article.

Symptoms and manifestations of food allergy, with particular relevance to the gut

Adverse reactions to ingested foods can cause a wide variety of symptoms, syndromes and diseases. Several different mechanisms may be implicated in organic (i.e. not psychologically based) reactions to foods, and these include IgE- and non-IgE-mediated immunological reactions-food allergies. Many specific conditions have now been recognised, and can be separated from the general body of food allergy/food intolerance disease; diagnostic criteria are recognised, and often a specific diagnostic test is available. For others, both to establish that reaction to food is involved, and to establish the foods implicated, diagnosis may require exclusion diet, open and/or double blind, placebo-controlled challenges, ideally monitored objectively. Manifestations of food allergy in the gut are described; and the relevance of digestive function, in relation to dose and distribution of allergens, is discussed.