抗禽流感或传染性喉气管炎两种重组鸡痘病毒疫苗联合免疫的相互影响

INFLUENCE ON IMMUNE EFFICACY OF TWO RECOMBINANT FOWLPOX VIRUS VACCINES AT DIFFERENT COMBINATION

"表达H5N1禽流感病毒HA和NA基因的重组鸡痘病毒(rFPV-AI)疫苗"以及"表达传染性喉气管炎病毒gB基因的重组鸡痘病毒(rFPV-ILT)疫苗"均已在实现商业化生产。由于两种疫苗使用了相同的载体病毒,如何使用才能减少相互干扰而产生最好的免疫效果。本研究设计了三个试验组:1)免疫rFPV-AI后间隔4周接种rFPV-ILT;2)rFPV-AI和rFPV-ILT混合后接种;3)将rFPV-AI和rFPV-ILT分别在两个翅膀同时免疫。结果表明,试验鸡接种rFPV-AI后4周接种rFPV-ILT,对传染性喉气管炎病毒WG株攻击的保护率为60%(6/10),低于rFPV-ILT单独免疫组的保护率(100%,10/10);rFPV-AI和rFPV-ILT混合后免疫组对禽流感病毒强毒攻击的保护率为80%(8/10),对传染性喉气管炎病毒强毒攻击的保护率为70%(7/10),而rFPV-AI和rFPV-ILT分两点同时接种对两种病毒攻击均能产生完全保护。本试验结果建议将这两种相同载体的重组病毒疫苗分两点同时接种以避免相互之间的干扰。

In China, two recombinant fowlpox viruses expressing either HA/NA of avian H5N1 influenza virus （rFPV-AI） or glycoprotein B of infectious laryngotracheitis virus （rFPV- ILT） have been commercialized. As the two vaccines shared the same vector （fowlpox virus）, we must apply them properly in order to reduce maximally the interference with each other. In this study,we designed three experiments： 1） chickens were initially immunized with rFPV- AI and subsequently immunized with rFPV- ILT after four weeks; 2） chickens were immunized with the mixture of two vaccines; 3） chickens were immunized at the left wing with rFPV- AI and at the right wing with rFPV- ILT simultaneously. The protective rate of chickens inoculated with two vaccines （4 weeks apart） against infectious laryngotracheitis virus WG strain is 60% （6/10）, which is lower than that of chickens inoculated with rFPV- ILT alone （100%, 10/10）; the group immunized with the mixed vaccine achieved 80% （8/10） and 70% （7/10） protection after challenges with H5N1 avian influenza virus and virulent infectious laryngotracheitis virus, respectively. However, the group inoculated with rFPV-AI and rFPV-ILT at different wings induced full protection against corresponding virus challenge. The results showed that immunization with the two recombinant fowlpox viruses at different points could avoid their mutual interference caused by vector virus.