Comparison of antibody responses to hen's egg and cow's milk proteins in orally sensitized rats and food‐allergic patients

Abstract

Upon daily intragastric exposure to food allergens, the specificities of the induced antibody responses in the BN rat resemble those found in food-allergic patients. These studies add further support to the hypothesis that the BN rat may provide a suitable animal model for food allergy research and research on the allergenicity of food proteins.

Assessment of protein allergenicity on the basis of immune reactivity: animal models.

“…Moreover, both IgG and IgE antibodies present in sera of rats sensitized orally to HEW or CM and in sera of HEW-or CM-allergic patients recognized a comparable profile of allergens in these food products. These results indicate that the specific protein recognition of induced antibodies in the BN rat is comparable with that observed in sera from allergic patients (Knippels et al 2000).…”

“…Although antigen-specific IgG responses were found upon daily gavage dosing of the animals with different concentrations of HEW or CM, only a limited number of IgE responders were observed as measured by PCA. However, immunoblotting experiments with these rat sera demonstrated the presence of specific IgE antibodies against both HEW proteins and CM proteins (Knippels et al 2000). Moreover, both IgG and IgE antibodies present in sera of rats sensitized orally to HEW or CM and in sera of HEW-or CM-allergic patients recognized a comparable profile of allergens in these food products.…”

Use of a rat basophil leukemia (RBL) cell-based immunological assay for allergen identification, clinical diagnosis of allergy, and identification of anti-allergy agents for use in immunotherapy

“…For example, the major allergens Gal d 1, Gal d 2, Gal d 3, Ara h 1, the Ara h 3/4 complex, and Bos d 5, and the minor allergens Gal d 4 and Bos d 8, were detected by both human and murine sera. In contrast, Ara h 2 was not detected by murine sera (Kaul et al, 2007;Knippels et al, 2000). Thus, the RBL cell-based immunological assay based on murine IgE may not be fully identical to those based on human IgE.…”

“…The immunization schedule based on repeated applications of low doses of allergens seems to be generally suitable to induce allergen-specific IgE in Balb/c mice (Hoffmann et al, 1997(Hoffmann et al, , 1999Kaul et al, 2007). Most major allergens can be recognized by both murine and human sera (Kaul et al, 2007;Knippels et al, 2000); however, to some extent, the recognized allergens may differ (Kaul et al, 2007). For example, the major allergens Gal d 1, Gal d 2, Gal d 3, Ara h 1, the Ara h 3/4 complex, and Bos d 5, and the minor allergens Gal d 4 and Bos d 8, were detected by both human and murine sera.…”

Has in vitro allergenicity testing any clinical relevance?

“…Brown Norway rats can be sensitized orally to various allergenic foods tested, resulting in significant antigen-specific IgE responses (16). The specificities of induced antibody responses in Brown Norway rats resemble those found in food-allergic patients (17). In 'at risk' patients oral tolerance can be induced by means of tolerogenic cow's milk peptides or hydrolysate (18).…”