1株类NADC30 PRRSV三谱系重组株的分离鉴定及遗传分析  

Isolation,identification and genetic analysis of a three-lineage NADC30 PRRSV recombinant strain

作　　者：蔡丙严[1] 乔洋洋 刘天昕 左伟勇[1] 王永娟[1] 张凯[1] 陆辉[1] 王海明 CAI Bingyan;QIAO Yangyang;LIU Tianxin;ZUO Weiyong;WANG Yongjuan;ZHANG Kai;LU Hui;WANG Haiming(Jiangsu Agri-animal Husbandry Vocational College,Taizhou,Jiangsu 225300,China;Harbin Veterinary Research Institute of Chinese Academy of Agricultural Sciences,Harbin 15000l,China)

机构地区：[1]江苏农牧科技职业学院,江苏泰州225300 [2]中国农业科学院哈尔滨兽医研究所,黑龙江哈尔滨150001

出　　处：《中国兽医学报》2025年第3期420-426,共7页Chinese Journal of Veterinary Science

基　　金：江苏农牧科技职业学院校内基金资助项目(NSF2023CB17,NSF2023CB06)。

摘　　要：2018年6月黑龙江佳木斯某猪场的母猪出现了大量流产,随后该场的断奶仔猪在35日龄左右开始出现持续高烧症状,部分猪体温超过41.5℃。为确定此次疫情的病因,本研究对来自本养殖场送检的63份临床样品进行检测。结果显示,63份样品中有60份样品呈现猪繁殖障碍与呼吸综合征病毒(porcine reproductive and respiratory syndrome virus,PRRSV)抗原阳性。随后将PRRSV抗原阳性病料接种于非洲绿猴胚胎肾细胞(Marc-145),盲传3代后,进行IFA(indirect immunofluorescence assay),结果显示,成功分离获得1株PRRSV,命名为HLJ38株。随后对HLJ38株进行了全基因组测序,并利用生物信息学软件对其基因组进行了详细分析,结果显示HLJ38株Nsp2基因的推导氨基酸序列中存在3处、共计131(323~433 aa、483 aa和504~522 aa)个氨基酸的缺失,符合类NADC30 PRRSV的分子遗传标志;进化树分析结果显示,HLJ38与GenBank中的类NADC30 PRRSV同属于谱系1亚群,与国内代表毒株CH-1a、HuN4亲缘关系较远,其核苷酸同源性仅为85.2%和84.6%;重组分析结果显示,HLJ38是1株重组的类NADC30 PRRSV,且重组的基因片段来源于多个毒株,其中1~201 nt片段由VR2332毒株提供,而6641~8061 nt来源于HP-PRRSV毒株。结果表明,该猪场此次疫情的原因可能是由不同谱系间PRRSV毒株发生重组所致,重组后的流行毒株不仅具有一定的致病性,而且现有的商品化疫苗对其交叉保护性较弱;不同谱系间的重组增加了PRRSV的基因多样性,也加剧了猪场PRRS防控的难度。因此,有必要持续监控猪场中PRRSV的流行动态,及时采取有效措施,遏制PRRS疫情的扩散。In June 2018,sows at a pig farm in Jiamusi,Heilongjiang Province,suffered a large number of miscarriages,and subsequently weaned piglets at the farm began to show persistent high fever symptoms at around 35 days of age,with some pigs having a fever of more than 41.5℃.In order to determine the cause of this outbreak,63 clinical samples from this farm were tested.The results showed that 60 out of 63 samples were positive for the porcine reproductive and respiratory syndrome virus(PRRSV)antigen.Subsequently,PRRSV antigen-positive plasmid was transfected into African green monkey embryonic kidney cells(Marc-145),and after three generations of blind transmission,indirect immunofluorescence assay(IF A)was performed.The results showed that one PRRSV strain,named HLJ38,was successfully isolated.Then the whole genome of HLJ38strain was sequenced and then analyzed in detail by bioinformatics software.Sequence analysis showed that there were three deletions of 131 amino acids(323-433 aa,483 aa and 504-522 aa)in the derived sequence of Nsp2 gene of HLJ38 strain,which was consistent with the molecular genetic marker of NADC30 PRRSV.The phylogenetic tree analysis showed that HLJ38 and NADC30 PRRSV in GenBank belong to lineage 1 subgroup,and the nucleotide homology of HLJ38and NADC30 PRRSV in GenBank was only 85.2%and 84.6%.Recombinant analysis showed that HLJ38 was a recombinant NADC30-like PRRSV,and the recombinant gene fragments were derived from multiple strains,among which the fragment of 1-201 nt was provided by VR2332strain and fragment of 6641-8061 nt derived from the HP-PRRSV strain.In summary,the results showed that the outbreak in this pig farm may be caused by the recombination of PRRSV strains among different lineages,and the recombinant circulating strains not only have certain pathogenicity but also suggest that the existing commercial vaccines provide limited cross-protection against them.Recombination between different lineages increases the genetic diversity of PRRSV and aggravates the difficulty of preventi

关 键 词：猪繁殖与呼吸综合征病毒 类NADC30 PRRSV HLJ38 重组分析 

分 类 号：S852.65[农业科学—基础兽医学]