肠毒素性大肠杆菌CS3纤毛抗原在痢疾菌中的表达及其免疫效果研究  

Expression of CS3 from Enterotoxigenic Escherichia coli in Shigella flexneri 2a and Immunologenicity of the Recombinant Strain

作　　者：韩照中[1] 应天翼[1] 曹勇[1] 芮贤良[1] 张兆山[1] 苏国富[1] 黄翠芬[1] 

机构地区：[1]北京生物工程研究所,北京100071

出　　处：《中国生物化学与分子生物学报》1999年第5期718-723,共6页Chinese Journal of Biochemistry and Molecular Biology

摘　　要：首先通过体内外重组的方法,构建了福氏2a痢疾菌T32asd基因缺陷的突变体FaD,作为抗原载体菌;同时,构建包含asd基因的表达质粒pYX102,与FaD一起,构成宿主-载体平衡致死系统,用于在没有抗生素条件选择的情况下,稳定表达克隆在表达质粒上的外源抗原基因.将肠毒素性大肠杆菌的CS3菌毛抗原基因克隆至pYX102,构建成重组表达质粒pYX103,ELISA检测结果证实CS3在痢疾菌中可以很好地表达.免疫小鼠后可诱生相应的抗体,虽然口服免疫和注射免疫产生的CS3抗体效价有一定差别,但对痢疾菌的毒株攻击均可提供较好保护.该结果为细菌性腹泻疫苗的研制提供了候选株.A host plasmid balancing system was established based on asd gene in a candidate vaccine strain(T32) of Shigella flexirie 2a. Asd gene of T32 was amplified by polymerase chain reaction(PCR), and its structural gene fragment was replaced by human interleukin 2 gene. The mutated asd gene was introduced to T32 genome by homological recombination. The resulted bacteria strain (FaD) was used as antigen carrier to express E.coli surface antigen CS3 of enterotoxigenic E. coli, which was expressed on a complementory plasmid carrying asd gene from streptococcus mutans. The plasmid could stably be maintained and expressed CS3 in the host cell without any antibiotic selection. Antibodies against CS3 could be detected in sera of mice immunimized with recombinant bacteria either orally or subcutaneously, and mice immunimized by either route could be protected from challenging with virulent strain of the same serotype. All results indicate that the recombinant constructed can be used as bi valent vaccine candidate for prevention of bacterial diarrhea.

关 键 词：疫苗 痢疾福氏2a菌 CS3纤毛抗原 表达 

分 类 号：R378.2[医药卫生—病原生物学] R516.401[医药卫生—基础医学]