宋内Ⅰ相O抗原及霍乱毒素B亚基在福氏2a痢疾菌中的表达及其免疫保护效果的观察

Expression of S.sonnei form Ⅰ Antigen Gene and V.cholerae Toxin B Subunit Gene in S. flexneri 2a Strain and Investigation of Their Immunoprotective Response in Mice

本文利用基因重组的方法，将宋内Ｉ相Ｏ抗原基因以及霍乱毒素Ｂ亚单位基因（ｃｔｘ－Ｂ）克隆至带链球菌的ａｓｄ基因的表达载体，然后转化至ａｓｄ－痢疾菌苗株福氏２ａＴ３２。脂多糖银染以及Ｗｅｓｔｅｒｎｂｌｏｔｔｉｎｇ实验证实以上两基因都能在宿主菌中稳定表达。动物（小白鼠）保护实验表明，该重组菌对福氏２ａ、宋内氏痢疾菌的保护效率达１００％，对霍乱弧菌的保护效率也达７０％。该菌具有稳定、无抗生素标记、多价的特点。

The genes encoding S.sonnei form I O antigen and V.cholerae B subunit were cloned into an expression vector containing as.gene of Streptococcus mutans by gene recombination.The final recombination plasmid was transformed into the asd mutant of S.flexneri 2a(strain T32).Analysis of LPS silver staining and western blotting indicated that the genes encoding CT-B and form I O antigen could stably express in the asd mutant T32 strain.Immune protection tests in mice showed that the recombinant strain constructed in this study could provide 100% protection against the challenge from S.flexneri 2a and S.sonnei and also showed a good immune protection(70%)against V.cholerae.This recombinant strain has the following adventages:trivalent,stable and no vector drug resistance markers.