SFTSV nonstructural protein NSs-mediated immunopathogenesis

SFTSV 非结构蛋白 NSs 介导的免疫发病机制

• 批准号: 10441349
• 负责人: Jae U Jung
• 金额: $ 60.42万
• 依托单位: CLEVELAND CLINIC LERNER COM-CWRU
• 依托单位国家: 美国
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-07-01 至 2024-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10441349
• 关键词: 2 year old; 4 year old; Age; Animal Model; Animals; Anti-Inflammatory Agents; Antiviral Agents; Autophagosome; Characteristics; China; Clinical; Code; Complex; Country; Dangerousness; Disease; Family; Far East; Fatality rate; Ferrets; Fever; Genes; Genome; Genus Phlebovirus; Host Defense; Human; Immune; Immune Evasion; Immunosuppression; In Vitro; Inclusion Bodies; Infection; Interferon Type I; Interferons; Interleukin-10; Leukocytes; Lipids; MAP3K8 gene; Mediating; Modeling; Molecular; Morbidity - disease rate; Mus; Nonstructural Protein; Nucleoproteins; Pathogenesis; Pathway interactions; Patients; Phosphotransferases; Play; Production; Protein Kinase; RNA; Recombinants; Reporting; Risk Factors; Role; Severe Fever with Thrombocytopenia Syndrome Virus; Signal Pathway; Signal Transduction; Source; Symptoms; TBK1 gene; TRIM25 gene; Therapeutic; Thrombocytopenia; Ticks; Time; Treatment Efficacy; Vaccines; Viral; Viral Pathogenesis; Virus; Virus Diseases; World Health Organization; age related; aged; base; clinical diagnosis; cytokine; in vivo; kinase inhibitor; mortality; mouse model; mutant; neutralizing antibody; novel; pathogen; protein kinase inhibitor; response; reverse genetics; transmission process; young adult

Project Summary/Abstract Severe fever with thrombocytopenia syndrome virus (SFTSV) listed in the World Health Organization 9 most dangerous pathogens is an emerging Phlebovirus in the Phenuiviridae family. Due to the lack of therapy and vaccine against SFTSV infection, there is a pressing need to understand the pathogenesis of SFTSV to develop effective antiviral agents. Designated as Biosafety level 3 agent, SFTSV contains a genome comprised of three segments of negative or ambisense RNA designated as large, medium, and small. The S segment encodes a nucleoprotein and a nonstructural protein (NSs) via an ambisense coding strategy. (Aim 1) We have discovered that NSs targets the Vps15-Vps34 lipid kinase complex to form virus-induced autophagosome-like inclusion bodies (IB), subsequently sequestrating IFN signaling effectors (RIG-I, TRIM25, and TBK1) to the IB and thereby suppressing IFN production. (Aim 2) We have also found that SFTSV NSs plays an essential role in viral immunopathogenesis by targeting the TPL2-ABIN2-p105 kinase complex to robustly induce expression of immune suppressive genes, specifically IL-10 cytokine. (Aim 3) We combined viral reverse genetics, a TPL2 kinase inhibitor, Tpl2-/- and il10-/- mouse models to show that the NSs-mediated activation of TPL2 signaling pathway robustly induced IL-10 production that was essential for viral pathogenesis. For the first time, we developed an age- dependent ferret model: young adult ferrets (<2 years old) did not show any clinical symptoms and mortality; however, SFTSV-infected aged ferrets (>4 years old) demonstrated severe thrombocytopenia, reduced white blood cells, and high fever with ~90% mortality rate, fully recapitulating human clinical manifestation. With well-established in vitro experimental conditions and novel in vivo animal models, the proposed study not only demonstrates the critical role of SFTSV NSs in viral immune evasion and pathogenesis, but also identifies potential therapeutic approaches to treat SFTSV-infected patients.

项目摘要/摘要 在世界健康中列出的血小板减少综合征病毒（SFTSV）严重发烧 组织9最危险的病原体是苯依维氏菌家族中新兴的静脉病毒。 由于缺乏治疗和针对SFTSV感染的疫苗，因此需要迫切需要 了解SFTSV的发病机理以开发有效的抗病毒药。指定为 生物安全3级代理，SFTSV包含一个基因组，该基因组由三个片段或负面或 Ambisense RNA指定为大，中和小。 S段编码核蛋白 以及通过Ambisense编码策略的非结构蛋白（NSS）。 （目标1）我们发现了 NSS靶向VPS15-VPS34脂质激酶复合物，形成病毒诱导的自噬体样 纳入体（IB），随​​后隔离IFN信号效应子（RIG-I，TRIM25和 TBK1）到IB，从而抑制了IFN生产。 （AIM 2）我们还发现SFTSV NSS通过靶向TPL2-ABIN2-P105激酶在病毒免疫发作中起着至关重要的作用 复合物至强诱导免疫抑制基因的表达，特别是IL-10细胞因子。 （AIM 3）我们将病毒反向遗传学，TPL2激酶抑制剂TPL2 - / - 和IL10 - / - 小鼠组合 模型表明NSS介导的TPL2信号通路的激活可鲁棒诱导IL-10 对病毒发病机理必不可少的产生。我们第一次开发了一个年龄 - 依赖雪貂模型：年轻的成年雪貂（<2岁）没有显示任何临床症状， 死亡;但是，SFTSV感染的老年雪貂（> 4岁）表现出严重的 血小板减少症，白细胞降低和高烧死亡率约为90％，完全 概括人类的临床表现。在良好的体外实验条件下 和新型的体内动物模型，拟议的研究不仅证明了 SFTSV NSS在病毒免疫逃避和发病机理中，但也鉴定出潜在的治疗性 治疗SFTSV感染患者的方法。