致病性F18大肠杆菌黏附素受体易感性仔猪的体外鉴定

在PCR-RFLP方法分析了不同猪个体FUT1基因M307位点等位基因多态性的基础上，制备M307位点为GG和AG2种类型仔猪小肠上皮细胞分别与表达F18ab菌毛的野生型大肠杆菌、表达F18ac菌毛含fed操纵子全基因的重组大肠杆菌及表面分泌表达F18ab菌毛FedF亚单位的重组大肠杆菌进行体外黏附和黏附抑制试验。结果表明，上述野生菌或重组菌对GG和AG2种基因型的30～35日龄断奶仔猪小肠上皮细胞均具有较好的黏附能力。上述3种大肠杆菌分别与抗F18ab纯菌毛血清、F18ac纯菌毛血清及抗F18ab菌毛FedF亚单位单因子血清作用后．则丢失黏附小肠上皮细胞能力。而GG基因型的3日龄仔猪小肠上皮细胞不能很好的黏附上述野生菌或重组菌．但是可以很好地黏附表达987P菌毛的大肠杆菌。

Genetically Susceptible Piglets of Small Intestinal Epithelium Receptors to Pathogenic F18 Fimbrial Escherichia coli Adhesin in Vitro

By the method of PCR-RFLP, the FUT1 M307 polymorphisms different pigs have been analysed, and base on the results of DNA polymorphisms, two types of small intestinal epithelium cells with the genotypes of FUT1 M307GG and M307AG have been selected to test the adhesion capability with the wide type Escherichia coli expressing F18ab fimbriae, the recombinant Escherichia coli expressing F18ac fimbriae or the recombinant Escherichia coli secreting and surface displaying the FedF subunit of F18ab fimbriae, respectively. The results showed that all these wide type and recombinant Escherichia coli mentioned above have the good capabilities to adhere to the post-weaning small intestinal epithelium cells with the genotypes of FUT1 M307GG and M307AG. All of these adhesion capability can be inhibited after the incubation between each bacteria and the corresponding anti-serium (Escherichia coli expressing F18ab fimbriae for the anti-serium against F18ab fimbriae, the recombinant Escherichia coli expressing F18ac fimbriae for the anti-serium against F18ac fimbriae),the recombinant Escherichia coli secreting and surface displaying the FedF subunit of F18ab fimbriae for the anti-serium against FedF subunit of F18ab fimbriae). On the other hand, the 3-days-old piglet small intestinal epithelium cells with FUT1 M307GG can not adhere to these wide type and recombinant Escherichia coli well, while they can very well adhere to the Escherichia coli expressing 987P fimbriae.