Xie Chang-Zhan, Zhang Ping, Wang Zheng, Tao Yi-Mo, Cui Zhuo-Dong, Nan Fu-Long, Zhang Fu-Chao, Ren Yun-Xin, Zhang He, Lu Hui-Jun
Institute of Urban Agriculture, Chengdu National Agricultural Science & Technology Center, Chinese Academy of Agricultural Sciences, Chengdu, China.
Key Laboratory of Special Animal Epidemic Disease, Institute of Special Animal and Plant Sciences, Chinese Academy of Agricultural Sciences, Changchun, China.
Front Vet Sci. 2024 Dec 17;11:1503526. doi: 10.3389/fvets.2024.1503526. eCollection 2024.
Porcine reproductive and respiratory syndrome virus (PRRSV) causes reproductive and respiratory diseases in sow herds and piglets. The emergence of ORF5 RFLP 1-7-4-like (NADC34-like) PRRSV strain in China has brought a new round of challenges to PRRSV prevention.
In addition, recombinant adenovirus vaccine candidates against the newly emerged NADC34-like strain were constructed in the study; the immunogenicity of the vaccine was investigated in piglets. After inoculation with PRRSV recombinant adenovirus, specific antibodies, neutralizing antibodies, and levels of IFN- and IL-4 cytokines were detected in serum.
Thirty-five days after immunization, the levels of IFN-γ and IL-4 cytokines in the pac-Ad5-34-GP3, pac-Ad5-34-GP5, and pac-Ad5-34-GP35 experimental groups were significantly higher ( < 0.05) than those of the PBS and the adenovirus group. All vaccines can cause corresponding Th1 and Th2 immune responses based on animal experimental results. After the challenge, no obvious clinical symptoms were observed in the immune groups compared with the control group, vaccinated animals could reduce the occurrence of viremia, and the occurrence of viremia was alleviated, with no obvious pathological changes in the lungs, indicating that recombinant adenovirus vaccine could provide a good protective immunity and produce a good humoral and cellular immune response at the same time.
It shows that the recombinant adenovirus vaccine group has better protection against the virus. Provide vaccine reserve and theoretical support for the emergence of new PRRSV subtypes in China.
猪繁殖与呼吸综合征病毒（PRRSV）可引起母猪群和仔猪的繁殖与呼吸疾病。中国ORF5 RFLP 1-7-4样（NADC34样）PRRSV毒株的出现给PRRSV的防控带来了新一轮挑战。
此外，本研究构建了针对新出现的NADC34样毒株的重组腺病毒候选疫苗；并在仔猪中研究了该疫苗的免疫原性。接种PRRSV重组腺病毒后，检测血清中的特异性抗体、中和抗体以及IFN-γ和IL-4细胞因子水平。
免疫35天后，pac-Ad5-34-GP3、pac-Ad5-34-GP5和pac-Ad5-34-GP35实验组的IFN-γ和IL-4细胞因子水平显著高于（P<0.05）PBS组和腺病毒组。基于动物实验结果，所有疫苗均可引发相应的Th1和Th2免疫反应。攻毒后，与对照组相比，免疫组未观察到明显临床症状，接种疫苗的动物可减少病毒血症的发生，且病毒血症的发生得到缓解，肺部无明显病理变化，表明重组腺病毒疫苗可提供良好的保护性免疫，同时产生良好的体液免疫和细胞免疫反应。
表明重组腺病毒疫苗组对病毒具有更好的保护作用。为中国新出现的PRRSV亚型提供疫苗储备和理论支持。
