Nebraska Center for Virology and School of Veterinary Medicine and Biomedical Sciences, University of Nebraska-Lincoln, Lincoln, NE 68583, USA.
Vaccine. 2013 Sep 13;31(40):4330-7. doi: 10.1016/j.vaccine.2013.07.020. Epub 2013 Jul 23.
DIVA (differentiating infected from vaccinated animals) vaccines have proven extremely useful for control and eradication of infectious diseases in livestock. We describe here the characterization of a serologic marker epitope, so-called epitope-M201, which can be a potential target for development of a live-attenuated DIVA vaccine against porcine reproductive and respiratory syndrome virus (PRRSV). Epitope-M201 is located at the carboxyl terminus (residues 161-174) of the viral M protein. The epitope is highly immunodominant and well-conserved among type-II PRRSV isolates. Rabbit polyclonal antibodies prepared against this epitope are non-neutralizing; thus, the epitope does not seem to contribute to the protective immunity against PRRSV infection. Importantly, the immunogenicity of epitope-M201 can be disrupted through the introduction of a single amino acid mutation which does not adversely affect the viral replication. All together, our results provide an important starting point for the development of a live-attenuated DIVA vaccine against type-II PRRSV.
DIVA（区分感染动物和接种疫苗动物）疫苗已被证明在控制和根除家畜传染病方面非常有用。我们在这里描述了一种血清学标记表位的特征，即所谓的表位-M201，它可能是开发针对猪繁殖与呼吸综合征病毒（PRRSV）的活疫苗的潜在目标。表位-M201 位于病毒 M 蛋白的羧基末端（残基 161-174）。该表位高度免疫显性，在 II 型 PRRSV 分离株中高度保守。针对该表位制备的兔多克隆抗体是非中和性的；因此，该表位似乎不会对 PRRSV 感染的保护性免疫产生贡献。重要的是，通过引入单个氨基酸突变可以破坏表位-M201 的免疫原性，而不会对病毒复制产生不利影响。总之，我们的研究结果为开发针对 II 型 PRRSV 的活疫苗提供了重要的起点。
