Plum Island Animal Disease Center, Agricultural Research Service, USDA, Greenport, NY, 11944, USA; Kansas State University, Manhattan, KS, 66506, USA.
Plum Island Animal Disease Center, Agricultural Research Service, USDA, Greenport, NY, 11944, USA.
Biologicals. 2023 Aug;83:101685. doi: 10.1016/j.biologicals.2023.101685. Epub 2023 Jun 3.
African swine fever (ASF) is a devastating disease that is currently producing a panzootic significantly impacting the swine industry worldwide. One of the major challenges for advancing the development of ASF vaccines has been the absence of international standards for ASF vaccine purity, potency, safety, and efficacy. To date, the most effective experimental vaccines have been live attenuated strains of viruses. Most of these promising vaccine candidates have been developed by deleting virus genes involved in the process of viral pathogenesis and disease production. This approach requires genomic modification of a parental virus field strain through a process of homologous recombination followed by purification of the recombinant attenuated virus. In this scenario, it is critical to confirm the absence of any parental virulent virus in the final virus stock used for vaccine production. We present here a protocol to establish the purity of virus stock using the live attenuated vaccine candidates ASFV-G-ΔMGF, ASFV-G-Δ9 GLΔUK and ASFV-G-ΔI177L. Procedures described here includes inoculation in susceptible pigs followed by the assessment of the obtained material by differential qPCRs that allows the identification of vaccine virus from ASFV field isolates. This protocol is proposed as a model to ensure that master seed virus stock used for vaccine production does not contain residual parental virulent virus. Procedures described here includes a passage in susceptible pigs followed by the assessment of the obtained material by differential qPCRs that allows the identification of vaccine virus from ASFV field isolates.
非洲猪瘟（ASF）是一种破坏性疾病，目前正在全球范围内引发一场大流行，对养猪业造成重大影响。推进 ASF 疫苗开发的主要挑战之一是缺乏 ASF 疫苗纯度、效力、安全性和功效的国际标准。迄今为止，最有效的实验疫苗是减毒活病毒株。这些有前途的候选疫苗大多是通过删除病毒在病毒发病和疾病产生过程中涉及的基因来开发的。这种方法需要通过同源重组对亲本病毒田间株进行基因组修饰，然后纯化重组减毒病毒。在这种情况下，必须确认最终用于疫苗生产的病毒储备中没有任何亲本毒病毒。我们在这里提出了一个使用活减毒疫苗候选株 ASFV-G-ΔMGF、ASFV-G-Δ9 GLΔUK 和 ASFV-G-ΔI177L 来确定病毒储备纯度的方案。这里描述的程序包括在易感猪中接种，然后通过差异 qPCR 评估获得的材料，允许从 ASF 田间分离株中鉴定疫苗病毒。该方案旨在确保用于疫苗生产的主种子病毒储备不含有残留的亲本毒病毒。这里描述的程序包括在易感猪中传代，然后通过差异 qPCR 评估获得的材料，允许从 ASF 田间分离株中鉴定疫苗病毒。
