The importance of dietary control in the development of a peanut allergy model in Brown Norway rats

Gene expression changes in the mesenteric lymph nodes of rats after oral peanut extract exposure

“…In previous experiments it has been shown that PE-specific IgE levels (de Jonge et al, 2007a), and the number of eosinophilic and basophilic granulocytes (de Jonge et al, 2007b) were higher in the BN rats exposed to 10 mg PE compared to those exposed to 1 mg PE. In addition, the ex vivo proliferation rates of the MLNs of BN rats exposed to 10 mg PE were also higher than those of the 1 mg PE group.…”

“…This peanut model has been tested for various conventional immune parameters (de Jonge et al 2007a(de Jonge et al , 2007b. In an earlier study (de Jonge et al, 2007b), we used PE in combination with the adjuvant cholera toxin as a positive control, and found that careful breeding for multiple generations on feed that excluded the protein of interest (PE) and cross-reactive proteins (soy) resulted in strong allergic responses in non-adjuvated animals that were similar to animals that were adjuvated with cholera toxin.…”

“…This peanut model has been tested for various conventional immune parameters (de Jonge et al 2007a(de Jonge et al , 2007b. In an earlier study (de Jonge et al, 2007b), we used PE in combination with the adjuvant cholera toxin as a positive control, and found that careful breeding for multiple generations on feed that excluded the protein of interest (PE) and cross-reactive proteins (soy) resulted in strong allergic responses in non-adjuvated animals that were similar to animals that were adjuvated with cholera toxin. In the current article, we repeat earlier results indicating that oral exposure to PE leads to specific antibody responses and specific lymphocyte proliferative responses, and in addition that oral exposure to PE results in gene expression profiles in the MLN that were associated with cell division and immunological processes.…”

“…This might be explained by the observation that the T-lymphocyte response after the encounter with an antigen peaks after 7 days (Haring and log IgG 2a and IgG 1 titers after PE-sensitization were higher on Day 14 than on Day 7. It should be mentioned that Days 3 and 7 are, in fact, too early to detect specific IgE responses, and even Day 14 is not optimal (de Jonge et al, 2007b). The early response in the MLN can be explained by the fact that the MLN is an immunologic organ that is at the frontline of the gutassociated immune response, whereas the production of food allergen-specific antibodies by B-lymphocytes takes place at a later moment in the response.…”

“…PE-specific IgE, IgG 1 , and IgG 2a Enzyme-Linked ImmunoSorbent Assay (ELISAs) were performed as described earlier (de Jonge et al, 2007b). Serum samples were collected at sacrifice at Days 3, 7 and 14.…”