Allergenic versus tolerogenic characteristics of cow’s milk hydrolysates

Cow’s milk allergy is a growing problem in the Western world, where if affects up to 2.5% of all infants. Currently, the only accepted and safe management of food allergy is exclusion of all offending foods from the diet. However for infants with cow’s milk allergy or infants with an increased risk for development of cow’s milk allergy, special infant formulas based on hydrolysed cow’s milk proteins are available. Extensively hydrolysed infant formulas are used primarily for children with an already diagnosed cow’s milk allergy (secondary prevention), whereas partially hydrolysed infant formulas are used primarily for infants predisposed for developing cow’s milk allergy (primary prevention). However, our knowledge about which characteristics of cow’s milk proteins that contributes to the development of allergy and which contributes to the prevention of allergy are very scarce. In order to establish knowledge-based strategies for production of new and improved hypo-allergenic infant formulas, we therefore need thorough studies investigating which properties of milk proteins that direct the immune system towards allergy and which that direct the immune system towards tolerance (primary or secondary prevention). Such studies must be conducted in animal models of food allergy.

The main objective of this project is to investigate and characterise the properties of cow’s milk based hydrolysates contributing to sensitisation (allergy induction) and the properties that prevents allergy by the induction of tolerance.

The project aims to establish two new animal models based on our own colony of Brown Norway rats to study: (1) induction of tolerance in non-allergic subjects (primary prevention) and (2) induction of tolerance in already sensitised subjects (secondary prevention). These models will together with our well-established model for examination of sensitising (allergy inducing) capacity of food proteins and their breakdown products form the basis for studying the properties of cow’s milk based hydrolysates contributing to allergy versus tolerance induction. A total of four extensively and four partially hydrolysed cow’s milk protein products will be tested in the three animal models. These hydrolysates will differ from each other in: (1) degree of hydrolysis, (2) peptide composition, (3) complex formation, (4) residual intact proteins and (5) starting material. Collectively this will allow us to provide knowledge for establishment of new and improved infant formulas for allergy prevention.

Project year 1 will focus on and end up with establishment of the two new animal models for testing of tolerance and project year 2 will focus on and end up with a panel of tests for ability of hydrolysates to induce allergy, primary prevention or secondary prevention. Results from this project will at first be presented at international conferences and at the latest in 2016 be published in Danish as well as in internationally peer-reviewed journals.