Lin Tao, Li Xiangrui, Yao Huochun, Wei Zuzhang, Tan Feifei, Liu Runxia, Sun Lichang, Zhang Rong, Li Wenliang, Lu Jiaqi, Tong Guangzhi, Yuan Shishan
College of Veterinary Medicine, Nanjing Agricultural University, No. 1 Weigang Street, Xuanwu District, Nanjing, People's Republic of China.
Virus Genes. 2012 Dec;45(3):548-55. doi: 10.1007/s11262-012-0812-z. Epub 2012 Aug 31.
Nucleocapsid (N) protein of porcine reproductive and respiratory syndrome virus (PRRSV) is the most abundant viral structural protein with high immunogenicity. Previously, the nonessential sequences for virus infectivity were identified at both N and C terminal ends of N protein. Here, by means of reverse genetics, a marker virus (v7APMa) was generated with a mutant N protein that differs from the wild-type strains (vAPRRS, type 2 PRRSV). v7APMa shows stable inheritance in cell culture and the virologic characteristics of the marker virus in vitro showed that v7APMa replicates well as its parental strain. In the pig model, the v7APMa marker virus induced a similar level of anti-N protein antibodies and robust antibodies against the marker peptide, from 14 days post infection. In addition, a peptide-based ELISA was developed to detect the specific antibodies for the introduced 7APMa peptide. This approach, using a rationally designed marker virus, provides a new potential mutant basis for further development of PRRSV novel vaccines.
猪繁殖与呼吸综合征病毒（PRRSV）的核衣壳（N）蛋白是最丰富的具有高免疫原性的病毒结构蛋白。此前，已在N蛋白的N端和C端鉴定出病毒感染性的非必需序列。在此，通过反向遗传学方法，构建了一种标记病毒（v7APMa），其N蛋白发生了突变，与野生型毒株（vAPRRS，2型PRRSV）不同。v7APMa在细胞培养中表现出稳定的遗传特性，且该标记病毒在体外的病毒学特征表明，v7APMa与其亲本毒株一样能良好复制。在猪模型中，v7APMa标记病毒从感染后14天起诱导产生了类似水平的抗N蛋白抗体以及针对标记肽的强抗体。此外，还开发了一种基于肽的ELISA方法来检测针对引入的7APMa肽的特异性抗体。这种利用合理设计的标记病毒的方法为PRRSV新型疫苗的进一步研发提供了新的潜在突变基础。
