Selection of Anti-Allergic Lactobacillus in Murine Model of Peanut Allergy / 소아알레르기및호흡기학회지

PURPOSE: To evaluate the anti-allergic effects of intragastric treatment with various strains of lactobacillus, we undertook this study in the murine model of peanut allergy. METHODS: Ten groups of mice were sensitized and boosted with 1 mg/dose of crude peanut intragastricly at day 1, 2, 3, 7 and 21. Also, each groups of mice was treated with various strains of lactobacillus or PBS starting on the 1st day of sensitization, for 3 weeks daily. During the experiment, peanut specific serum IgE, IgG1, IgG2a were measured at weekly intervals, and compared at week four which is one week after the end of lactobacillus treatment. RESULTS: By treatment with various strains of lactobacillus, peanut specific IgE levels were decreased in all treated groups of mice compared to sham-treated mice. And at least six of the 10 groups of mice treated with various strains of L. casei or L. acidophilus showed remarkable down-regulatory effects on the production of peanut specific IgE antibodies, while the regulatory effects on specific IgG1, and IgG2a antibodies were variable. Especially, L. casei IBS041 showed harmonized regulatory effect on the productions of peanut specific IgE, IgG1 and IgG2a. CONCLUSION: We selected and partly confirmed several strains of lactobacillus which showed anti-allergic effects in the production of antigen specific IgE in the murine model of peanut allergy.

Effect of Cosensitization with Buckwheat Flour Extract on the Production of House Dust Mite-specific IgE

There are studies reporting food sensitization in infancy increases the risk of sensitization to inhalants later in life. We performed a study to evaluate whether cosensitization with buckwheat (BW) has an effect on the production of house dust mite-IgE. C3H/HeJ mice (4 weeks, female) were sensitized with house dust mite (HDM)/Al (OH)3, intraperitoneally on day 0, followed by 4 intranasal sensitizations (on days 14, 15, 16, and 21). Group 1 was cosensitized intragastrically with BW/cholera toxin (CT) (on days 0, 1, 2, 7, and 18) during sensitization with HDM, group 2 was cosensitized intragastrically with CT only (on days 0, 1, 2, 7, and 18), and group 3 was used as controls. HDM- and BW-IgE and antigen-specific T-cell proliferation and cytokine production were evaluated. In Group 1, BW-IgE levels were highest at week 4, and the HDM-IgE at week 3 (98.45+/-64.37 ng/mL and 169.86+/-55.54 ng/mL, respectively). In Group 2, HDM-IgE levels reached a peak at week 3, remarkably higher (810.52+/-233.29 ng/mL) compared to those of Group 1 (169.86+/-55.54 ng/mL). The interleukin (IL)-4 and interferon (IFN)-gamma in the HDM-stimulated culture supernatants of splenocytes were not significantly different among groups. We postulate that the cosensitization with BW may down-regulate the specific IgE response to HDM.

Murine Model of Buckwheat Allergy by Intragastric Sensitization with Fresh Buckwheat Flour Extract

Food allergies affect about 4% of the Korean population, and buckwheat allergy is one of the most severe food allergies in Korea. The purpose of the present study was to develop a murine model of IgE-mediated buckwheat hypersensitivity induced by intragastric sensitization. Young female C3H/HeJ mice were sensitized and challenged intragastricly with fresh buckwheat flour (1, 5, 25 mg/dose of proteins) mixed in cholera toxin, followed by intragastric challenge. Anaphylactic reactions, antigen-specific antibodies, splenocytes proliferation assays and cytokine productions were evaluated. Oral buckwheat challenges of sensitized mice provoked anaphylactic reactions such as severe scratch, perioral/periorbital swellings, or decreased activity. Reactions were associated with elevated levels of buckwheatspecific IgE antibodies. Splenocytes from buckwheat allergic mice exhibited significantly greater proliferative responses to buckwheat than non-allergic mice. Buckwheat-stimulated IL-4, IL-5, and INF-gamma productions were associated with elevated levels of buckwheat-specific IgE in sensitized mice. In this model, 1 mg and 5 mg dose of sensitization produced almost the same degree of Th2-directed immune response, however, a 25 mg dose showed blunted antibody responses. In conclusion, we developed IgE-mediated buckwheat allergy by intragastric sensitization and challenge, and this model could provide a good tool for future studies.