文献类型： 外文期刊

作者： Wang, H. -M. ¹ ; Liu, Y. -G. ¹ ; Tang, Y. -D. ¹ ; Liu, T. -X. ¹ ; Zheng, L. -L. ¹ ; Wang, T. -Y. ¹ ; Liu, S. -G. ¹ ; Wang ¹ ;

作者机构： 1.Chinese Acad Agr Sci, Harbin Vet Res Inst, State Key Lab Vet Biotechnol, Harbin, Heilongjiang, Peoples R China

关键词： genetic diversity; NADC30-like PRRSV; pathogenicity; porcine reproductive and respiratory syndrome virus (PRRSV); recombination

期刊名称：TRANSBOUNDARY AND EMERGING DISEASES （ 影响因子：5.005； 五年影响因子：4.622 ）

ISSN： 1865-1674

年卷期： 2018 年 65 卷 4 期

页码：

收录情况： SCI

摘要： Porcine reproductive and respiratory syndrome virus (PRRSV) is a major economically significant pathogen that has adversely affected China's swine industry. Currently, a novel type 2 PRRSV, called the NADC30-like strain, is epidemic in numerous provinces of China, and commercial vaccines provide limited protection for infected animals. The extensive recombination phenomenon among NADC30-like PRRSVs is identified as a unique molecular characteristic of the virus. However, our understanding of how recombination influences NADC30-like PRRSVs is largely inadequate. In this study, we analysed the genetic characteristics of a recombinant NADC30-like PRRSV (SC-d) and examined its pathogenicity compared with a non-recombinant NADC30-like PRRSV (SD-A19) and a highly pathogenic PRRSV (HuN4). SC-d has three discontinuous deletions in nsp2, consistent with NADC30 isolated from the United States in 2008. Furthermore, we identified four recombination breakpoints in the SC-d genome, which separated the SC-d genome into four regions (regions A, B, C and D). Regions A and C are closely related to the JXA1-like strain, one of the earliest Chinese HP-PRRSV strains, and regions B and D are closely related to the NADC30 strain. Moreover, SC-d inoculated piglets exhibited a persistent fever, moderate weight loss, mild thymus atrophy and obvious microscopic lung lesions. In summary, the recombinant NADC30-like PRRSV SC-d strain displayed a higher pathogenicity than the non-recombinant NADC30-like PRRSV SD-A19 strain; however, the pathogenicity of the NADC30-like PRRSV SC-d was lower compared with the HP-PRRSV HuN4 strain in piglets. Our findings demonstrate that recombination is responsible for the enormous genetic diversity and pathogenicity variance of the NADC30-like PRRSV in China. This study provides a theoretical basis for developing a more reasonable PRRSV control and prevention strategy.