A new animal model for cow's milk allergy: Usefull tool for epitope testing

Introduction: Cow's milk hydrolysates contain less allergic epitopes. They are used for prevention to avoid sensitization or as therapy in allergic children. In a mouse model using a skin response as readout, the allergenicity of a partial hydrolysate (pHF) was tested in both the sensitization and the effector phase of the allergic response. This is indicative for prevention or treatment, respectively. Methods: C3H/ HeOuJ mice were sensitized orally with whey proteins using cholera toxin as adjuvant. The primary readout is an acute ear swelling response upon challenge with whey. To test the allergenicity of the pHF on effector phase, whey-sensitized mice were ear challenged with pHF. The sensitizing capacity of pHF was tested by oral sensitization with pHF using cholera toxin and subsequent ear challenge with whey. Results: Acute ear swelling correlates with specific IgE and IgG levels. Whey-sensitized mice challenged with pHF showed 60% reduction in acute skin reaction. Oral sensitization with pHF diminished ear swelling to whey by 60%. In contrast to sensitization with whey, pHF did not elicit any whey-specific IgE response. Conclusions: A partial whey hydrolysate diminished both sensitization and the effector phase in a mouse model for cow's milk allergy. This model involves an oral route of sensitization, acute allergic skin responses as primary readout and induction of specific serum Ig's.