NADC34-like porcine reproductive and respiratory syndrome virus(PRRSV),which first appeared in China in 2017,is currently one of the main epidemic strains in China.In this study,we found that a new variant of NADC34-l...NADC34-like porcine reproductive and respiratory syndrome virus(PRRSV),which first appeared in China in 2017,is currently one of the main epidemic strains in China.In this study,we found that a new variant of NADC34-like PRRSV evolved,named the L1A variant.The phylogenetics,epidemic status,and pathogenicity of the LA variants were subsequently comprehensively evaluated.Based on the results of the ORF5 phylogenetic analysis,the L1A variants were classified as NADC34-like PPRSV.All the strains had the same discontinuous 131-aa deletion in the NSP2 region(similar to that in the NADC30).Recombination analysis revealed that the L1A variants were recombinant viruses that contained an NADC30-like PRRSV skeleton,a nonstructural protein-encoding gene region obtained in part from JXA1-like PRRSV and a ORF2-ORF6 gene region partly obtained from NADC34-like PRRSV and that exhibited similar recombination patterns.We successfully isolated the L1A variant TZJ2756 from PAMs and Marc-145 cells.In animal experiments,TZJ2756 exhibited moderate pathogenicity in piglets,causing obvious clinical symptoms,namely,persistent fever,significantly reduced body weight,interstitial edema and severe interstitial pneumonia in the lungs,and prolonged high-load viremia.L1A variants have been detected in at least 12 provinces in China and share many similar epidemiological characteristics with the American L1C variant.This research will enhance our understanding of the prevalence of L1A variants and furnish valuable data for the ongoing monitoring of NADC34-like PRRSV in China.展开更多
猪繁殖与呼吸综合征(Porcine Reproductive and Respiratory Syndrome,PRRS)主要是由猪繁殖与呼吸综合征病毒(Porcine Reproductive and Respiratory Syndrome Virus,PRRSV)所引起的,该病症在母猪群体中,主要表现为流产、产出死胎、弱...猪繁殖与呼吸综合征(Porcine Reproductive and Respiratory Syndrome,PRRS)主要是由猪繁殖与呼吸综合征病毒(Porcine Reproductive and Respiratory Syndrome Virus,PRRSV)所引起的,该病症在母猪群体中,主要表现为流产、产出死胎、弱仔以及木乃伊胎;在仔猪群体里,则以呼吸功能出现障碍以及罹患败血症为显著特征。PRRSV有着较快的传播速度和较强的传染性,这使得PRRS在规模化养猪场中成为一种常见的接触性传染病。PRRSV的流行对养猪业造成严重的经济影响。科学防治PRRS需要对病原生物学,特别是病原感染机制的知识。因此,本文从PRRSV的基因组结构,各个病毒编码蛋白的功能、特别是病毒蛋白在感染中的作用机制等方面进行综述,旨在为PRRSV的研究以及制定相应的防控策略提供参考。展开更多
基金supported by grants from the National Natural Science Foundation of China(32172890 and 32002315)the National Key Research and Development Program of China(2022YFF0711004)+3 种基金the Natural Science Foundation of Heilongjiang Province,China(YQ2022C042)the State Key Laboratory of Veterinary Biotechnology Foundation of China(SKLVBF202208)the Postdoctoral Fellowship Program of CPSF,China(GZC20233062)the National Center of Technology Innovation for Pigs,China(NCTIP-XD/C09)。
文摘NADC34-like porcine reproductive and respiratory syndrome virus(PRRSV),which first appeared in China in 2017,is currently one of the main epidemic strains in China.In this study,we found that a new variant of NADC34-like PRRSV evolved,named the L1A variant.The phylogenetics,epidemic status,and pathogenicity of the LA variants were subsequently comprehensively evaluated.Based on the results of the ORF5 phylogenetic analysis,the L1A variants were classified as NADC34-like PPRSV.All the strains had the same discontinuous 131-aa deletion in the NSP2 region(similar to that in the NADC30).Recombination analysis revealed that the L1A variants were recombinant viruses that contained an NADC30-like PRRSV skeleton,a nonstructural protein-encoding gene region obtained in part from JXA1-like PRRSV and a ORF2-ORF6 gene region partly obtained from NADC34-like PRRSV and that exhibited similar recombination patterns.We successfully isolated the L1A variant TZJ2756 from PAMs and Marc-145 cells.In animal experiments,TZJ2756 exhibited moderate pathogenicity in piglets,causing obvious clinical symptoms,namely,persistent fever,significantly reduced body weight,interstitial edema and severe interstitial pneumonia in the lungs,and prolonged high-load viremia.L1A variants have been detected in at least 12 provinces in China and share many similar epidemiological characteristics with the American L1C variant.This research will enhance our understanding of the prevalence of L1A variants and furnish valuable data for the ongoing monitoring of NADC34-like PRRSV in China.
文摘猪繁殖与呼吸综合征(Porcine Reproductive and Respiratory Syndrome,PRRS)主要是由猪繁殖与呼吸综合征病毒(Porcine Reproductive and Respiratory Syndrome Virus,PRRSV)所引起的,该病症在母猪群体中,主要表现为流产、产出死胎、弱仔以及木乃伊胎;在仔猪群体里,则以呼吸功能出现障碍以及罹患败血症为显著特征。PRRSV有着较快的传播速度和较强的传染性,这使得PRRS在规模化养猪场中成为一种常见的接触性传染病。PRRSV的流行对养猪业造成严重的经济影响。科学防治PRRS需要对病原生物学,特别是病原感染机制的知识。因此,本文从PRRSV的基因组结构,各个病毒编码蛋白的功能、特别是病毒蛋白在感染中的作用机制等方面进行综述,旨在为PRRSV的研究以及制定相应的防控策略提供参考。
