The Research Of Safety Evaluation Method Of Genetically Modified Food

Parti Study on allergenicity model of primary generation of BN ratObjective To confirm the feasibility of BN rats as the protein allergy animal model. Method48female BN rats were randomly divided into6groups, control group, PAP group, HEWP group, OVA-Low group, OVA-middle group, OVA-high group, each group had8rats. The above groups were administrated1ml sterilized water,1mg/ml PAP,10mg/ml HEWP,0.1mg/ml OVA,1mg/ml OVA or l0mg/ml OVA solution, respectively daily for6weeks by gavage. Blood samples were taken on the14th,28th and42nd days from the orbital plexus, and centrifuged to obtain serum for analyzing specific IgG. On the21st and35th days, blood samples were taken to obtain the plasma for histamine analysis. In addition, the changes of blood pressure and gut permeability were determined. Result Different concentrations of allergen OVA could stimulate allergic reaction in BN rats, including elevated specific IgG, elevated histamine level. The allergic reactions to Weak allergens (HEWP) were weak, allergic reactions to non-allergen (PAP) were negative. Blood pressure had no obvious changes in different time of all groups. Gastrointestinal function had no obvious physiological changes for all groups.Inflammatory disease of heart, liver, spleen, lung, kidney was not caused by Allergen. Conclusion BN rat could be a suitable animal model to evaluate food protein allergy. Part2The experiment of three generations allergenicity of BN ratsObjective Observe the three-generation rats exposure under different conditions (OVA solution or sterilized water), the immune response rats induced by allergens, and further improve the sensitivity evaluation of animal model of BN rats. Methods Every generation had two sensitized model, F1generation (Modell, Model2), F2generation (Mode3, Mode14), F3generation (Model4, Mode15). Different models were exposure different background. Each model rats were randomly divided into OVA group and control group by weight and sex,8male and8female rats in each group. Each group was administrated1mg/ml OVA solution or1ml sterilized water, respectively daily for6weeks by gavage. Blood samples were taken on the14th.28th and42nd days from the orbital plexus, and centrifuged to obtain serum to analyzespecific IgG, IgE and total IgE. On the21st and35th days, blood samples were taken to obtain plasma for histamine analysis. In addition, the changes of biochemical Blood and pathology were determined. Results Each model of immune reaction level to allergen was different, while parental rats were exposure in different conditions.The IgG level in parental rats serum that was non-exposure to allergen was higher than first generation, second generation, third generation were exposure to the allergen. The high IgG levels were induced after parental first generation exposure to allergen, the parental second generation, the parental third generation of non-exposure to allergen.The specific IgE, total IgE and histamine levels of each models were no significant difference. Conclusion While parental rats decendent generations were exposure to allergens, the offspring of rats were tolerance to allergen, parental rats that non-exposured to allergens, their offspring had non-tolerance to allergen. If BN rats were not exposured with allergen one generation that can be used as a better sensitized animal model for genetically modified food allergic evaluation.