Assessment of protein allergenicity: studies in brown norway rats

For the safety evaluation of genetically engineered crops, the potential allergenicity of the newly introduced protein(s) has become an important issue. There is, however, no universal and reliable test system for the evaluation of the allergic sensitizing ability of food proteins. Therefore, there is a growing interest in the development of animal models. This paper summarizes the results of a promising food allergy model developed in Brown Norway (BN) rats. The results demonstrate that BN rats can be sensitized via the relevant oral route of exposure. Daily gavage dosing of the animals with several food proteins, without the use of adjuvants, resulted in significant antigen-specific IgE responses. In addition, the profile of allergens recognized by the immune system of the BN rat, appeared comparable to the profile of allergens recognized by allergic humans. Besides oral sensitization, local and systemic immune-mediated effects, such as increased gastrointestinal permeability, decreased breathing frequency, and decreased blood pressure, could also be observed in the sensitized animals after an oral challenge. All together, these observations suggest that this BN rat model might provide a suitable animal model to study the allergenicity of food proteins in humans.