猪布鲁菌S2 omp10基因缺失株的构建及特性

Construction and characterization of a omp10-deficient Brucella suis S2 strain

现有的布鲁菌减毒活疫苗存在一定毒力,且野强毒株和减毒活疫苗株间缺少可供鉴别的抗原,导致在血清学检测上自然感染与疫苗接种很难区分,限制了现有的减毒活疫苗的广泛应用。本文拟对布鲁菌的减毒活疫苗株S2进行遗传改造,克服上述缺陷。本研究利用同源重组的方法,得到了布鲁菌S2株omp10基因缺失株。分别用基因缺失株和疫苗株感染小鼠,比较基因缺失株小鼠体内的存活能力。结果成功构建了布鲁菌S2株omp10基因缺失株,动物试验结果表明,基因缺失株仍能在小鼠体内存活,具备作为减毒活疫苗的特性。与原始S2株比较,基因缺失株的感染力进一步减弱。表明omp10基因在布鲁菌的毒力及体内生存方面发挥了作用,为基因标记疫苗的研制奠定了基础。

The wide application of live attenuated vaccine strains is limited because of drawbacks of residual virulence,similar antigenicity to virulent strain and the difficulty to differentiate vaccination and natural infection in serology detection.In this study,we modified the vaccine suis S2 strain to prevent the drawbacks.By using homologous recombination,we replaced the omp10 gene in a live attenuated vaccine strain S2.The omp10-deficient Brucella suis S2 strain and S2 were used to infect mice to compare their survival capability.A omp10-deficient Brucella suis S2 strain was success fully constructed.Results from mice infection showed that the new strain could survive in mice,indicating the feasibility as live attenuated vaccine strain and infection capability decreased.The conclusion is that the gene omp10 may be impact on Brucella virulence and survival capability in vivo.The study provide a new candidate for further tagged vaccine development.