Canadian Science Center for Human and Animal Health, Public Health Agency of Canada, 1015 Arlington Street, Winnipeg, Manitoba, Canada R3E 3P6.
Virus Res. 2012 Feb;163(2):431-8. doi: 10.1016/j.virusres.2011.11.002. Epub 2011 Nov 12.
Kyasanur Forest Disease Virus (KFDV) is a tick-borne, hemorrhagic fever-causing member of the Flaviviridae virus family. With infections annually ranging from 50 to 1000 people in south-west India and the lack of effective treatments, a better understanding of this virus is needed. The development of a reverse genetics system (RGS) for KFDV would provide the opportunity to address these issues. The KFDV genome sequence was elucidated and the RGS was created. Utilizing this system, live infectious KFDV particles were produced from mammalian cell culture, thereby validating the success of the RGS. Flaviviruses have the ability to suppress the type 1 interferon response and indications are that the non structural (NS) proteins serve this role. Using luciferase bioassays, the NS5 protein of KFDV was determined to be the primary antagonist of the IFN response when compared to the other NS proteins, specifically NS4B and NS4B-2k. Moreover, our results indicate that this is attributed to a region, beginning before and including the RNA-dependent RNA polymerase (RdRp). With evasion of the interferon response by KFDV established, the further implementation of the reverse genetics system will enable investigation into pathogenesis and disease progression of KFDV with respect to the innate immune response, at the IFN and the NS5 protein levels.
基孔肯雅热病毒（KFDV）是一种由蜱传播的、引起出血热的黄病毒科病毒。在印度西南部，每年有 50 到 1000 人感染该病，而且目前缺乏有效的治疗方法，因此我们需要更好地了解这种病毒。建立基孔肯雅热病毒的反向遗传学系统（RGS）将为解决这些问题提供机会。我们阐明了 KFDV 的基因组序列并创建了 RGS。利用该系统，我们从哺乳动物细胞培养物中产生了活的传染性 KFDV 颗粒，从而验证了 RGS 的成功。黄病毒具有抑制 I 型干扰素反应的能力，有迹象表明非结构（NS）蛋白发挥了这一作用。通过荧光素酶生物测定，与其他 NS 蛋白（特别是 NS4B 和 NS4B-2k）相比，KFDV 的 NS5 蛋白被确定为 IFN 反应的主要拮抗剂。此外，我们的结果表明，这归因于一个区域，该区域始于 RNA 依赖性 RNA 聚合酶（RdRp）之前并包含 RdRp。KFDV 逃避干扰素反应的机制已经建立，进一步实施反向遗传学系统将能够研究 KFDV 对固有免疫反应的发病机制和疾病进展，包括 IFN 和 NS5 蛋白水平。
