Evaluation of the suitability of β-lactoglobulin and whey protein in a BALB/ c mouse model of cow's milk allergy

Cow's milk allergy (CMA) is common in infants and young children, which can adversely affect their growth and quality of life. Currently, research on CMA is mainly carried out in mouse models due to ethical constraints in population studies, but the determination of the optimal modelling protocol remains controversial. Here, we aim to evaluate the applicability of beta-lactoglobulin (BLG) and whey protein from multiple perspectives in the construction of CMA models in BALB/c mice. To this end, the mice were sensitized by oral gavage of allergens, and then challenged by BLG or whey protein orally administered as well as whey intradermally in the ear, respectively. The allergic reactions were determined by the evaluation of anaphylactic symptoms, levels of specific immunoglobulins and Th2 cytokines, and intestinal tissue histopathology. Overall, mice in the BLG group showed more severe allergic symptoms and decreased body temperature than the other groups. The stronger allergic reactions to BLG in mice were also proved in higher levels of mouse mast cell protease-1 (mMCP-1), allergen specific antibodies, and Th2 cytokines as well as more serious intestinal damage than whey protein. These results suggest that BALB/c mice vary in the susceptibility to different cow's milk allergens, and the single component represented by BLG instead of whey protein, may be a more appropriate and effective allergen for the construction of BALB/c mouse model of CMA.