Pasteurella multocida is the main cause of several infections of farm animals, and the immunity gained from commercial vaccines is for the short term only and needs to be routinely administered, so work on new vaccines against virulent P. multocida is crucial. In this study, the OmpH gene was amplified from ten P. multocida strains, and the PCR products were sequenced and analyzed. The results of RFLP analysis of OmpH gene digested by MspI enzyme showed that all of ten strains examined possessed one restriction site and two fragments, 350 and 650 bp. The OmpH sequence of strain No. 10 was cloned into bacterial expression vector pUCP24, and the recombinant pUCP24-OmpH was expressed in E. coli DH5α. Serum samples obtained from the ELISA test from a group of vaccinated rats indicate that the antibodies were present at high titer in immunized rats and can be tested as a vaccine candidate with a challenge. In rats infected with the DNA vaccine and inactivated vaccine, a significant increase in serum antibody levels was observed. In addition, the DNA vaccine provided the vaccinated rats with partial protection; however, the protective efficacy was greater than that offered by the live attenuated vaccine. This successful recombinant vaccine is immunogenic and may potentially be used as a vaccine in the future.

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一种针对多杀巴斯德氏菌的潜在 DNA 疫苗的免疫反应和保护功效

多杀巴斯德氏菌是农场动物多次感染的主要原因，商业疫苗获得的免疫力只是短期的，需要定期接种，因此开发针对多杀巴斯德氏菌的新疫苗至关重要。本研究从十个多杀疟原虫菌株中扩增了 OmpH 基因，并对 PCR 产物进行了测序和分析。MspI酶切OmpH基因的RFLP分析结果表明，检测的10株菌株均具有1个酶切位点和2个片段，分别为350和650bp。将10号菌株的OmpH序列克隆到细菌表达载体pUCP24中，重组pUCP24-OmpH在大肠杆菌DH5α中表达。从一组接种疫苗的大鼠的 ELISA 测试中获得的血清样本表明，这些抗体在免疫大鼠中以高滴度存在，可以作为候选疫苗进行测试。在感染了 DNA 疫苗和灭活疫苗的大鼠中，观察到血清抗体水平显着增加。此外，DNA疫苗为接种疫苗的大鼠提供了部分保护；然而，保护效力大于减毒活疫苗提供的保护效力。这种成功的重组疫苗具有免疫原性，未来有可能用作疫苗。DNA疫苗为接种疫苗的大鼠提供了部分保护；然而，保护效力大于减毒活疫苗提供的保护效力。这种成功的重组疫苗具有免疫原性，未来有可能用作疫苗。DNA疫苗为接种疫苗的大鼠提供了部分保护；然而，保护效力大于减毒活疫苗提供的保护效力。这种成功的重组疫苗具有免疫原性，未来有可能用作疫苗。