源于亲本株PRV Fa的3个基因缺失病毒株PRV TK^-、PRV gE^-/gI^-和PRV TK^-/gE^-/gI^-抵抗强毒攻击的比较研究(英文)  

Evaluation of the vaccinations with three strains of gene-deleted mutants from pseudorabies virus,PRV TK^-,PRV gE^-/gI and PRV TK^-/gE^-/gI^-after exposure to the wild Fa strain

作　　者：颜其贵[1] 阳爱国[2] 郭万柱[1] 徐志文[1] 石谦[2] 殷华平[1] 

机构地区：[1]四川农业大学动物医学院,四川雅安625014 [2]四川省动物防疫监督总站,四川成都610041

出　　处：《中国人兽共患病学报》2008年第9期827-835,共9页Chinese Journal of Zoonoses

摘　　要：目的4周龄仔猪24头随机分成4个组(A、B、C和对照组),前3组中各5头分别对应接种对应的缺失毒力基因TK(A)、缺失毒力基因gE/gI(B)和缺失毒力基因TK/gE/gI(C)3个基因缺失株,接种剂量均为105PFU,留1头不接种作为同居猪。免疫14d后以107PFU PRV Fa株滴鼻攻毒所有试验猪,7d后屠宰猪只,采集大脑、小脑、心脏、肝脏、肺脏、脾脏、肾脏、扁桃体、下颌淋巴结和三叉神经节,用光镜和电镜技术观察PRV攻毒后仔猪的器官损伤程度。收集免疫接种后3d内和强毒攻击后5d内的所有猪只鼻腔拭纸,以Southern blots方法测定PRV的组织分布情况。结果表明,收集的10种组织中出现病变的组织比例分别为:对照组为9/10,免疫A组为4/10、B组为3/10、C组为4/10。病理学和超微病例观察表明,对照组和A组中肺脏损伤严重,其他组轻微;对照组中大脑、小脑、三叉神经损伤严重,免疫组轻微;A、B和C疫苗株对潜伏感染的主要靶器官扁桃体损伤程度依次加重。Southern blots分析表明,所有接种缺失病毒的试验猪均可通过鼻腔分泌物散毒,但是排出的病毒不能成功感染同居猪;A、B和C疫苗株免疫后均不能有效阻止PRV Fa攻击后的散毒,但在仔猪大脑和小脑中不能检出病毒。结论接种3个不同基因缺失株A、B和C均能阻止强毒株Fa感染后向大脑和小脑的入侵,并减少强毒对多个器官的损害作用,其中C株的抗强毒感染能力和抗强毒所致损伤能力更佳。To evaluate the value of the vaccinations with 3 strains of gene-deleted mutants from pseudorabies virus （PRV）, PRV TK^- , PRV gE^-/gI^- and PRV TK^-/gE^-/gI^- after to exposure to the wild Fa strain, these mutant strains from the PVR reference isolate Fa were used to vaccinate 4 weeks old PRV-free pigs with a dosage of 10^5 PFU each ,and followed by nasally challenged by the parental Fa strain with a dosage of 10^7 PFU at 14 days post vaccination. The pathological changes, virus discharge and distribution were evaluated after vaccination and challenge. It was found that the histopathological observations in the 10 collected samples including cerebrum, cerebellum, heart, liver, lungs, spleen, kidneys, tonsils, lymph nodes and trigeminal ganglion from these 3 mutant strains showed that the rates of occurrence of pathological changes in various organs were 4/10, 3/10 and 4/10 respectively, whereas that of the positive controls were 9/10. The damage in lungs was more serious in pigs vaccinated with PRV TK^- mutant and positive control in comparison with other groups of pigs inoculated, and the damages in cerebrum, cerebellum and trigeminal ganglion in positive controls were more serious than those of pigs vaccinated with the 3 gene-deleted mutants. However, the tonsils, the main organ for latent infection were damaged mildly in the pigs inoculated with these 3 gene-deleted mutants in comparison with that of the positive controls. As demonstrated by Southern blot analysis, all the vaccinated pigs could discharge viruses by secretion through nasal cavity, but the soldier pigs were not infected successively by the gene-deleted mutants and the gene-deleted mutants were also unable to establish infection in cerebrum and cerebellum. Nevertheless, they could not effectively block discharge of PRV Fa after exposure to Fa virus, but could block effectively the virulent Fa virus invading into cerebrum and cerebellum. From these observation, it is evident that the deleted mutants of the TK, gE/gI , TK/gE/gI genes can block

关 键 词：伪狂犬病毒 基因缺失疫苗株 免疫 病理 

分 类 号：S858.2[农业科学—临床兽医学]