Effect Of Bar Transgenic Rice On Immunological Function In Mice

Four experiments were set up to explore whether the PAT enzyme from Bar genetically modified (Bar-GM) rice has potential allergenicity or not, and also conducted a preliminary exploration about the effect on immune systems of KM mice whose feedstuff contains Bar-GM rice for a long period of time.1. Protein bioinformatics detection:database SDAP, Farrp and NCBI were used to detect the homology between amino acid sequence of PAT and all the known antigenic determinants in these three databases, through the assessment of E-values, the length and consistency percentage. Three-dimensional conformation of PAT was formed in SWISS-MODEL, and then found out all the proteins whose spatial structures were highly similar to PAT through PDB and PHYRE. By analyzing the characteristics of known proteins, to speculate whether the PAT is allergenicity.2. Animal feeding experiment:60KM mice were divided randomly into two groups, rationed respectively by the feed contains Bar-GM rice and the same strain normal rice in the same dose. After90days,20of each group were sampled at random to detect the IgE and DAO content in their blood serums and sIgA in their small intestines mucus with ELISA, lasting for three generations, and based on which we could judge whether the mice had developped allergies, and the intestinal immune barrier system had suffered impairment or not. 3. Lysozyme determination:10of each group were sampled to collect serum from their blood, keep fresh at-20℃and tested the Lysozyme activity by the measure of nephelometery to detect the humoral immunity impact.4. Lymphocyte transformation test:another10mice from the two groups were sampled for assay of the splenic cell and the blood Lymphocyte transformation rate by CCK-8.Results:there is no positive match through the protein-bioinformatics comparison, PAT has no homology with any of the known allergens. The three-dimensional conformation inspection indicate that PAT has a similar structure with other members in NAT-SF. There is little or no possibility to cause anaphylactic reaction. The three test indexes of ELISA all show no significant difference between these two groups(P>0.05). The preliminary results indicated that there was no significant difference of lysozyme activity between these two groups(1.740±0.121vs1.830±0.098, P=0.0769>0.05), the same as the splenic cell and the blood lymphocyte testing results(0.7104±0.0118vs0.7279±0.0076, P=0.233>0.05;0.4465±0.0310vs0.4799±0.0264, P=0.171>0.05).Conclusion:under the experimental conditions supplied, a conclusion could arrived that forage with bar-transgenic rice is not sensitized to the mice. Lysozyme activity and the transformation rate neither of splenic cell nor the blood lymphocyte were abnormal, the immune system of mice has not been threatened.