猪繁殖与呼吸综合征病毒NADC30-like株的分离鉴定及基因组分析OA北大核心CSTPCD

Porcine reproductive and respiratory syndrome(PRRS)is becoming a global epidemic,causing significant economic losses to the global pig industry.In order to improve the selection of PRRSV isolation cell types and understand the current genetic variation status of porcine reproductive and respiratory syn-drome virus(PRRSV)in Xinjiang,this study used freshly prepared pig bone marrow cells to induce differ-entiation into porcine bone marrow derived macrophages.A PRRSV virus strain named XJYQ-2021 was i-solated from the lungs of a suspected PRRSV infected pig farm in Xinjiang,and the entire genome was ob-tained through sequencing,homology,genetic evolution,and recombination analysis on the NSP2 amino acid sequence deletion,ORF5,and whole genome sequence of the virus strain;Identification was conducted using indirect immunofluorescence assay,and growth curves were plotted for the 10th,15th,and 20th gen-eration virus solutions.The results showed that the purity of induced differentiation of porcine bone mar-row-derived macrophages reached over 90％,and the XJYQ-2021 isolate grew well in this cell type,show-ing obvious cytopathic effects;Through the growth curve,it can be observed that the virus content increa-ses with the increase of generations,and the virus titer reaches its peak around 48 hours after infection;The total genome length of this isolate is 15 030 nt,with 90％homology with the American type NADC30;Compared with VR2332,the XJYQ-2021 isolate showed the same discontinuous deletion(111+1+19)in the amino acid sequence of NSP2 as the American type NADC30;The results of whole gene recombination analysis indicated that the XJYQ-2021 isolate is a recombinant virus with a recombinant fragment,among which NADC30 is a parent virus strain that was obtained through recombination with JXA1.The results of this study provide optimal cells for the isolation of PRRSV virus,as well as the genetic evolution of PRRSV epidemic strains in the Xinjiang region.