Sirard J C, Weber M, Duflot E, Popoff M R, Mock M
Unité des Toxines et Pathogénie Bactériennes, URA1858, Centre National de la Recherche Scientifique, Institut Pasteur, Paris,
Infect Immun. 1997 Jun;65(6):2029-33. doi: 10.1128/iai.65.6.2029-2033.1997.
The Bacillus anthracis toxinogenic Sterne strain is currently used as a live veterinary vaccine against anthrax. The capacity of a toxin-deficient derivative strain to produce a heterologous antigen by using the strong inducible promoter of the B. anthracis pag gene was investigated. The expression of the foreign gene ibp, encoding the Ib component of iota toxin from Clostridium perfringens, was analyzed. A pag-ibp fusion was introduced by allelic exchange into a toxin-deficient Sterne strain, thereby replacing the wild-type pag gene. This recombinant strain, called BAIB, was stable and secreted large quantities of Ib protein in induced culture conditions. Mice given injections of live BAIB spores developed an antibody response specific to the Ib protein. The pag-ibp fusion was therefore functional both in vitro and in vivo. Moreover, the immunized animals were protected against a challenge with C. perfringens iota toxin or with the homologous Clostridium spiroforme toxin. The protective immunity was mediated by neutralizing antibodies. In conclusion, B. anthracis is promising for the development of live veterinary vaccines.
炭疽芽孢杆菌产毒素斯特恩菌株目前用作预防炭疽的兽用活疫苗。研究了一种毒素缺陷衍生菌株利用炭疽芽孢杆菌pag基因的强诱导型启动子产生异源抗原的能力。分析了编码产气荚膜梭菌埃塔毒素Ib组分的外源基因ibp的表达。通过等位基因交换将pag-ibp融合基因导入毒素缺陷型斯特恩菌株，从而取代野生型pag基因。这种重组菌株称为BAIB，在诱导培养条件下稳定且分泌大量Ib蛋白。注射活BAIB孢子的小鼠产生了针对Ib蛋白的特异性抗体反应。因此，pag-ibp融合基因在体外和体内均具有功能。此外，免疫动物对产气荚膜梭菌埃塔毒素或同源螺旋体梭菌毒素的攻击具有抵抗力。保护性免疫由中和抗体介导。总之，炭疽芽孢杆菌在兽用活疫苗的开发方面很有前景。
