Hypoallergenicity: a principle for the treatment of food allergy

Food allergy is a common disease with the treatment of choice being complete avoidance of the incriminated food. In cow's milk allergy a hypoallergenic milk substitute is necessary during infancy and childhood. Hypoallergenic formulas are produced through enzymatic hydrolysis of different sources such as bovine casein or whey followed by further processing such as heat treatment and/or ultrafiltration. According to the degree of protein hydrolysis the resulting products have been classified into 'extensively' or 'partially' hydrolyzed. Reduction of allergenicity should be assessed in vitro and in vivo. Hypoallergenic formulas might also be based on amino acid mixtures. These elementary diets can be considered as nonallergenic. Several novel therapies are currently being explored in food allergy. One of the most promising approaches is the immunotherapy with mutated proteins. For this approach, alteration of the IgEbinding sites through single amino acid substitution is performed resulting in reduced to complete loss of IgE binding. For the major peanut allergens such mutations were introduced into the cDNA sequences and successfully expressed as hypoallergenic recombinant proteins. In peanut-sensitized mice, the use of these modified proteins co-administered with adjuvant such as heat-killed Escherichia coli showed promising results for future therapeutic approaches.