摘要
2023年11月,甘肃省临夏市某羊场羔羊死亡,根据临床症状、病理剖检及实时荧光定量RT-PCR结果诊断为小反刍兽疫病毒(PPRV)感染。采用RT-PCR扩增PPRV流行株全基因组序列,比对分析全基因组及其F基因、H基因和N基因序列,绘制进化树。为探讨不同效价PPRV疫苗毒株Nigeria75/1对绵羊外周血单个核细胞(PBMCs)增殖和分化的影响,采用CCK-8检测PBMCs的增殖情况,流式细胞术对CD4+和CD8+T淋巴细胞进行分型分析。结果显示:PPRV流行毒株基因组全长15954 bp,属于基因Ⅳ型;该流行毒株与2013—2014年小反刍兽疫疫情分离毒株China/XJYL/2013、China/3/2013及China/GS/2018的亲缘关系最近。另外,不同效价的PPRV疫苗毒株Nigeria75/1均抑制绵羊PBMCs体外增殖,且高效价的PPRV疫苗毒株抑制CD4^(+)和CD8^(+)T淋巴细胞的分化。以上结果表明,引起此次PPRV感染的毒株可能来源于2013—2014年小反刍兽疫疫情。PPRV疫苗重复免疫或高剂量免疫可能是造成我国PPRV疫苗免疫后仍然会感染和发病的原因。
A case of peste des petits ruminants(PPR)caused lamb death was found in a sheep farm in Linxia,Gansu Province,in November 2023.The disease was diagnosed by clinical symptoms,pathological autopsy observation and real-time RT-PCR detection.The whole genome sequence of the peste des petits ruminants virus(PPRV)epidemic strain was amplified by RT-PCR.Genetic analysis was carried out based on the whole genome,F gene,H gene and N gene sequences obtained in this study and reference sequences from GenBank.The effects of PPRV vaccine strain on the proliferation and differentiation of sheep peripheral blood mononuclear cells(PBMCs)were investigated by CCK-8 reagent and flow cytometry.The results showed that the epidemic strain China/GS/2023 responsible for the PPR case belonged to genotype IV,with a total length of 15954 bp.Phylogenetic analysis showed that the epidemic strain was closely related to China/XJYL/2013,China/3/2013,and China/GS/2018.In addition,different titers of live-attenuated PPRV vaccine strain Nigeria75/1 could inhibit the proliferation of sheep PBMCs in vitro,while high titers of PPRV vaccine strain Nigeria75/1 inhibited the differentiation of CD4^(+)and CD8^(+)in T lymphocytes.These results suggest that the infection of China/GS/2023 may be originated from the 2013-2014 PPR epidemic.In addition,application of the PPRV vaccine incorrectly including repeated immunization and over-dose of immunization may also be the causes of re-infection and outbreak of PPR cases in China.
作者
刘萍
杜国玉
柳周斌
聂帅帅
吴锦艳
曹小安
何继军
尚佑军
LIU Ping;DU Guoyu;LIU Zhoubin;NIE Shuaishuai;WU Jinyan;CAO Xiao'an;HE Jijun;SHANG Youjun(State Key Laboratory for Animal Disease Control and Prevention/Lanzhou Veterinary Research Institute,Chinese Academy of Agricultural Sciences,Lanzhou 730046,China;Animal Husbandry and Veterinary Station,Tonghua Town,Zhuanglang County,Pingliang 744600,China)
出处
《中国兽医科学》
北大核心
2025年第5期645-654,共10页
Chinese Veterinary Science
基金
国家现代农业产业技术体系专项(CARS-39-04B)
国家绒毛用羊产业技术体系专项(CARS-39-13)
甘肃省科技特派团专项(22CX8NA012)
国家重点研发计划项目(2021YFD1800504,2022YFD1602203,2022YFD1302101)。
关键词
小反刍兽疫病毒
病理剖检
遗传进化分析
流行病学
peste des petits ruminants virus
pathological necropsy
genetic analysis
epidemiology
