不同种属动物小肠上皮细胞与β-Conglycinin抗原表位结合受体表达与分布的比较研究

Soybean-induced allergic reaction is of common occurrence in animal production, and there occurs great different sensitivity to soybean between different animal species. However, its allergic mechanism is not clear to us. So finding out the relevant mechanism brings us economic significance and theoretical value for soybean protein feed utilization. In this study, different animal species (piglets, calves, chicken, mice) were selected to feed the dehulled soybean meal in order to compare the different sensitivity to soybean allergen by recording the diarrhea rate, sensitive skin test, sera IgG and specific IgE content. The β-Conglycinin epitope would be predicted and identified using the methods of bioinformatics, immunoaffinity mass spectrometry, and ELISA. The expression and distribution of epitope-binding receptor would be compared in the intestinal epithelium of different animal species by ELISA, western Blotting, and immunohistochemistry. These results would reveal the difference of β-Conglycinin–induced allergic reaction between species, which could provide the basis of antigen purification, quantity detection and seeking effective blocker, and further explore the allergic mechanism. Furthermore, it is significant to enrich the theory of comparative animal nutrition, improve feed utilization and food/feed safety.

畜禽生产中由大豆抗原引发的过敏现象普遍存在，且不同种属动物对大豆敏感性差异悬殊，但导致这些差异的相关机制尚不清楚，了解这些机理对于合理利用大豆蛋白饲料有重大经济价值和理论意义。本项目选取不同种属动物(仔猪、犊牛、雏鹅、鼠）饲喂去皮豆粕，通过检测腹泻率、皮肤试敏、血清总IgE和特异性IgG含量，来比较不同种属动物对大豆抗原致敏反应的差异；采用生物信息学法、免疫亲和质谱技术、ELISA等方法预测和鉴定大豆抗原蛋白β-Conglycinin的抗原表位；采用ELISA法，蛋白印迹法、免疫组化法检测小肠上皮与β-Conglycinin抗原表位结合受体的表达与分布情况。本项目将揭示不同种属动物对大豆抗原蛋白致敏差异的相关机制，这为日后抗原纯化、定量检测、寻求有效过敏阻断剂提供理论基础，并为深入揭示大豆过敏机理服务。另外，项目对于丰富比较动物营养学理论、优化动物饲料利用、保障饲料及食品安全均有重要意义。

畜禽生产中由大豆抗原引发的过敏现象普遍存在，且不同种属动物对大豆敏感性差异悬殊，但导致这些差异的相关机制尚不清楚。本项目选取不同种属动物饲喂去皮豆粕，通过检测特异性IgG含量及其抗体效价，来比较不同种属动物对大豆抗原致敏反应的差异。结果发现不同种属动物对大豆抗原蛋白敏感性存在差异，犊牛最敏感，仔猪次之，大鼠最不敏感。采用免疫亲和质谱技术、ELISA、斑点杂交等方法鉴定并比较了不同种属动物对大豆抗原蛋白β-Co nglycinin敏感的抗原表位区域。结果表明大豆抗原蛋白β-conglycinin与不同动物过敏血清发生特异性结合的的线性抗原表位敏感区域存在着显著差异。在选择的七个表位肽段中，α2（SPQLQNLR）、β2（LLQRF）、β3（QGFSHNILETSFHSEF）三个表位肽与仔猪致敏血清的结合能力最强。采用免疫组化法检测小肠上皮与β-Conglycin in抗原表位结合受体的表达与分布情况。结果表明不同种属动物肠上皮粘膜与β-Conglycinin抗原蛋白结合的分布情况存在差异。大豆致敏组仔猪和大鼠肠粘膜抗原结合蛋白明显高于非致敏组；β-Conglycinin与仔猪、大鼠和鹅肠粘膜结合蛋白在小肠前半段结合量高于后半段，而犊牛在空肠中段结合最多。本项目将揭示不同种属动物对大豆抗原蛋白致敏差异的相关机制。另外，项目结论对于合理利用大豆蛋白饲料有重大经济价值和理论意义。