The genc CPA and ETX encoding α and e toxins were amplified from the standard strain C60-2 of type D Clostridium perfingens by PCR, and then they were inserted into pet-Duct-1 vecto, respectively for the construction...The genc CPA and ETX encoding α and e toxins were amplified from the standard strain C60-2 of type D Clostridium perfingens by PCR, and then they were inserted into pet-Duct-1 vecto, respectively for the construction of co-expression plasmid pETDoet-1-CPA-ETX. The co-expression plasmid was transformed into BL21 （DE3） competent cells, at and e toxins proteins were induced by IPTG before analysis by SDS-PAGE. As a result, both of α and e toxins were detected at 43 and 34 KU by western-blot. Mice immunized with the co-expressed α and e toxins proteins produced high titers of neutralizing antibodies in the serum, which protected the mice against the attack of type D C. perfringens culture filtrate. In addition, mice immunized with the produced co-expressed α and e toxins proteins showed significantly higher surviving rate than with ε toxins protein alone when infected with culture filtrate of type D C. perfringens . These results indicated that co-expression of α and e toxins proteins could be used as a new method to prepare vaccines against the pathogens of multiple serotypes.展开更多
为获得腐败梭菌α毒素和D型产气荚膜梭菌ε毒素的共表达产物,并鉴定其致死活性和反应原性,评价其免疫保护效力,利用PCR扩增腐败梭菌α毒素和产气荚膜梭菌ε毒素基因Gcsa和Gcpe并克隆至pETDuet-1质粒,转化E.coli BL21(DE3),自诱导培养基...为获得腐败梭菌α毒素和D型产气荚膜梭菌ε毒素的共表达产物,并鉴定其致死活性和反应原性,评价其免疫保护效力,利用PCR扩增腐败梭菌α毒素和产气荚膜梭菌ε毒素基因Gcsa和Gcpe并克隆至pETDuet-1质粒,转化E.coli BL21(DE3),自诱导培养基诱导这2段基因共表达;用SDS-PAGE和Western-blot以及小鼠毒性试验、抗毒素血清中和试验对表达产物进行鉴定;将诱导后的大肠杆菌灭活,制成铝佐剂疫苗1 m L/只皮下注射免疫家兔2次,测定免疫血清中和抗体效价,用1 MLD的腐败梭菌毒素和D型产气荚膜梭菌毒素分别攻击。结果显示,所构建的E.coli BL21(pETDuet-Gcsa-Gcpe)可以同时表达Gcsa和Gcpe,表达产物能够与腐败梭菌和D型产气荚膜抗毒素血清反应;且具有小鼠致死毒性,只有用2种抗毒素一同作用,才能将其毒性中和;制成灭活疫苗免疫家兔,免疫血清对腐败梭菌毒素的中和抗体效价为2 MLD/0.1 m L,对D型产气荚膜梭菌毒素的中和抗体效价≥50 MLD/0.1 m L;用2种毒素攻击,免疫组家兔全部保护,对照组全部死亡,达到《中华人民共和国兽药典》(2015版)效力检验标准。结果表明,所构建的表达载体可以实现α毒素和ε毒素的活性共表达,本研究为腐败梭菌和产气荚膜梭菌的多联基因工程灭活疫苗的研究提供了实验基础。展开更多
基金Supported by the Basic Scientific Research Project of Nonprofit Central Research Institutions(1610322013028)
文摘The genc CPA and ETX encoding α and e toxins were amplified from the standard strain C60-2 of type D Clostridium perfingens by PCR, and then they were inserted into pet-Duct-1 vecto, respectively for the construction of co-expression plasmid pETDoet-1-CPA-ETX. The co-expression plasmid was transformed into BL21 （DE3） competent cells, at and e toxins proteins were induced by IPTG before analysis by SDS-PAGE. As a result, both of α and e toxins were detected at 43 and 34 KU by western-blot. Mice immunized with the co-expressed α and e toxins proteins produced high titers of neutralizing antibodies in the serum, which protected the mice against the attack of type D C. perfringens culture filtrate. In addition, mice immunized with the produced co-expressed α and e toxins proteins showed significantly higher surviving rate than with ε toxins protein alone when infected with culture filtrate of type D C. perfringens . These results indicated that co-expression of α and e toxins proteins could be used as a new method to prepare vaccines against the pathogens of multiple serotypes.
文摘为获得腐败梭菌α毒素和D型产气荚膜梭菌ε毒素的共表达产物,并鉴定其致死活性和反应原性,评价其免疫保护效力,利用PCR扩增腐败梭菌α毒素和产气荚膜梭菌ε毒素基因Gcsa和Gcpe并克隆至pETDuet-1质粒,转化E.coli BL21(DE3),自诱导培养基诱导这2段基因共表达;用SDS-PAGE和Western-blot以及小鼠毒性试验、抗毒素血清中和试验对表达产物进行鉴定;将诱导后的大肠杆菌灭活,制成铝佐剂疫苗1 m L/只皮下注射免疫家兔2次,测定免疫血清中和抗体效价,用1 MLD的腐败梭菌毒素和D型产气荚膜梭菌毒素分别攻击。结果显示,所构建的E.coli BL21(pETDuet-Gcsa-Gcpe)可以同时表达Gcsa和Gcpe,表达产物能够与腐败梭菌和D型产气荚膜抗毒素血清反应;且具有小鼠致死毒性,只有用2种抗毒素一同作用,才能将其毒性中和;制成灭活疫苗免疫家兔,免疫血清对腐败梭菌毒素的中和抗体效价为2 MLD/0.1 m L,对D型产气荚膜梭菌毒素的中和抗体效价≥50 MLD/0.1 m L;用2种毒素攻击,免疫组家兔全部保护,对照组全部死亡,达到《中华人民共和国兽药典》(2015版)效力检验标准。结果表明,所构建的表达载体可以实现α毒素和ε毒素的活性共表达,本研究为腐败梭菌和产气荚膜梭菌的多联基因工程灭活疫苗的研究提供了实验基础。
