Abril-Gil Mar, Garcia-Just Alba, Pérez-Cano Francisco J, Franch Àngels, Castell Margarida
Departament de Fisiologia, Facultat de Farmàcia, Universitat de Barcelona, Barcelona, Spain; Institut de Recerca en Nutrició i Seguretat Alimentària, Universitat de Barcelona (INSA-UB), Barcelona, Spain.
PLoS One. 2015 Apr 29;10(4):e0125314. doi: 10.1371/journal.pone.0125314. eCollection 2015.
Food allergy (FA) is an adverse health effect produced by the exposure to a given food. Currently, there is no optimal animal model of FA for the screening of immunotherapies or for testing the allergenicity of new foods.
The aim of the present study was to develop an effective and rapid model of FA in Brown Norway rats. In order to establish biomarkers of FA in rat, we compared the immune response and the anaphylactic shock obtained in this model with those achieved with only intraperitoneal immunization.
Rats received an intraperitoneal injection of ovalbumin (OVA) with alum and toxin from Bordetella pertussis, and 14 days later, OVA by oral route daily for three weeks (FA group). A group of rats receiving only the i.p. injection (IP group) were also tested. Serum anti-OVA IgE, IgG1, IgG2a, IgG2b and IgA antibodies were quantified throughout the study. After an oral challenge, body temperature, intestinal permeability, motor activity, and mast cell protease II (RMCP-II) levels were determined. At the end of the study, anti-OVA intestinal IgA, spleen cytokine production, lymphocyte composition of Peyer's patches and mesenteric lymph nodes, and gene expression in the small intestine were quantified.
Serum OVA-specific IgG1, IgG2a and IgG2b concentrations rose with the i.p. immunization but were highly augmented after the oral OVA administration. Anti-OVA IgE increased twofold during the first week of oral OVA gavage. The anaphylaxis in both IP and FA groups decreased body temperature and motor activity, whereas intestinal permeability increased. Interestingly, the FA group showed a much higher RMCP II serum protein and intestinal mRNA expression.
These results show both an effective and relatively rapid model of FA assessed by means of specific antibody titres and the high production of RMCP-II and its intestinal gene expression.
食物过敏（FA）是由接触特定食物所产生的不良健康影响。目前，尚无用于免疫疗法筛选或新食物致敏性测试的最佳食物过敏动物模型。
本研究旨在建立一种有效且快速的棕色挪威大鼠食物过敏模型。为了确定大鼠食物过敏的生物标志物，我们将该模型中获得的免疫反应和过敏性休克与仅通过腹腔免疫获得的结果进行了比较。
大鼠腹腔注射卵清蛋白（OVA）与明矾及百日咳博德特氏菌毒素，14天后，连续三周每日经口给予OVA（食物过敏组）。另一组仅接受腹腔注射的大鼠（腹腔注射组）也进行了测试。在整个研究过程中对血清抗OVA IgE、IgG1、IgG2a、IgG2b和IgA抗体进行定量。经口激发后，测定体温、肠道通透性、运动活性和肥大细胞蛋白酶II（RMCP-II）水平。在研究结束时，对抗OVA肠道IgA、脾脏细胞因子产生、派尔集合淋巴结和肠系膜淋巴结的淋巴细胞组成以及小肠中的基因表达进行定量。
血清OVA特异性IgG1、IgG2a和IgG2b浓度随腹腔免疫而升高，但在经口给予OVA后大幅增加。抗OVA IgE在经口给予OVA灌胃的第一周增加了两倍。腹腔注射组和食物过敏组的过敏反应均使体温和运动活性降低，而肠道通透性增加。有趣的是，食物过敏组的RMCP II血清蛋白和肠道mRNA表达要高得多。
这些结果表明，通过特异性抗体滴度评估，该模型是一种有效且相对快速的食物过敏模型，并且RMCP-II产生量高及其肠道基因表达也很高。
