Characterisation and therapeutic manipulation of Flaviviridae innate immune evasion

黄病毒科先天免疫逃避的特征和治疗操作

• 批准号: MR/S023380/1
• 负责人: Gregory Towers
• 金额: $ 53.68万
• 依托单位: University College London
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2019
• 资助国家: 英国
• 起止时间: 2019 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=MR%2FS023380%2F1
• 关键词: Characterisation; therapeutic; manipulation; Flaviviridae; innate

Flavirviridae include hepatitis C virus (HCV) and the insect transmitted viruses dengue virus (DV) and Zika virus (ZV). DV and ZV are emerging infections, spreading to new regions of the world, in part due to climate change expanding insect vector ranges. Currently around 60 million people suffer symptomatic DV infection each year with 10,000 deaths. It will be increasingly important to understand how to develop new antivirals as new infectious agents emerge and old agents spread. Cyclophilins (Cyps) are host enzymes that alter the shape of target proteins, but have poorly understood cellular functions. Critically, Cyps are widely found to act as cofactors for viral infection and HCV, DV and ZV all depend on Cyps for replication. Cells are very good at protecting themselves from infection using a variety of mechanisms termed cell autonomous innate immunity. This complex system detects incoming and replicating viruses using sensors that detect molecular patterns that are specific to the pathogen. Sensor triggering activates production interferon, which is secreted and induces expression of a whole host of antiviral proteins and pathways that potently suppress infection in nearby cells. Successful viruses must evade or antagonise these protective systems. Typically viruses hide from the sensors in a process we term cloaking. Flaviviridae hide by subverting the intracellular membrane system, cloaking their replication complexes in a membranous web. This excludes key sensors allowing unhindered RNA and viral protein production and viral assembly. Our preliminary data demonstrate that inhibiting Cyps uncloaks HCV revealing it to sensors including the RNA sensor RIG-I. This is evidenced by production of interferon when Cyp use by the virus is disturbed. Cyp inhibition is a powerful approach to developing antivirals because the antiviral effect is mediated by the host innate immune system, which is potent and difficult for the virus to escape. Targeting host factors makes the virus behave like a virus which doesn't infect humans because it activates and succumbs to innate immune defences.Our key discovery was to find that HCV doesn't require Cyps if its target cells have a defective innate immune system. This revealed that the virus uses Cyps to evade innate immunity. Here we aim to understand exactly how Flaviviridae use Cyps to evade innate immune protective systems. We will identify the specific Cyps used and test whether our novel Cyp inhibitors can suppress replication. We will identify the viral proteins targeted by Cyps and work out what Cyps do structurally to the virus proteins to help the virus hide. Our drug series distinguishes between different viruses and we will work out how. We will test which Cyps are targeted by the active drugs to explain the antiviral specificity that we see. We will study the membranous web and viral replication compartment and see how it changes when we disturb Cyp activity. Do the sensors enter the replication compartment and get activated when Cyps are disturbed? We will also study the innate immune system and identify the active sensors that detect the virus when we reveal it. All of these aims use tried and tested techniques in use in our or collaborators' laboratories. Our work will generate critical understanding of how host factors can protect viruses from innate immunity and how this interaction can be disturbed as a novel therapeutic or prophylactic strategy. Our goal is to generate new knowledge detailing the molecular mechanisms of the process of innate immune evasion by Flaviviridae and the consequences of disturbing it. We propose that this new knowledge and the demonstration of the tractability of host targeting strategies will be necessary before such strategies can be taken to the clinic as effective therapeutics.

黄病毒科包括丙型肝炎病毒（HCV）和昆虫传播病毒登革热病毒（DV）和寨卡病毒（ZV）。DV和ZV是新出现的感染，传播到世界新的地区，部分原因是气候变化扩大了昆虫病媒的范围。目前，每年约有6 000万人患有有症状的DV感染，其中1万人死亡。随着新的传染性病原体的出现和旧病原体的传播，了解如何开发新的抗病毒药物将变得越来越重要。亲环素（Cyps）是改变靶蛋白的形状的宿主酶，但对细胞功能知之甚少。重要的是，广泛发现Cyps作为病毒感染的辅因子，HCV、DV和ZV都依赖Cyps进行复制。细胞非常善于使用称为细胞自主先天免疫的各种机制来保护自己免受感染。这个复杂的系统使用传感器检测传入和复制的病毒，传感器检测病原体特有的分子模式。传感器触发激活干扰素的产生，干扰素被分泌并诱导整个宿主的抗病毒蛋白和途径的表达，这些蛋白和途径有效地抑制附近细胞的感染。成功的病毒必须避开或对抗这些保护系统。典型的病毒隐藏在传感器的过程中，我们称之为伪装。黄病毒科通过破坏细胞内膜系统，将它们的复制复合物隐藏在膜网中。这排除了允许不受阻碍的RNA和病毒蛋白质生产和病毒组装的关键传感器。我们的初步数据表明，抑制Cyps使HCV暴露于包括RNA传感器RIG-I在内的传感器。当病毒对Cyp的利用受到干扰时，干扰素的产生就证明了这一点。CYP抑制是开发抗病毒药物的有效方法，因为抗病毒作用是由宿主先天免疫系统介导的，这是有效的，并且病毒难以逃脱。靶向宿主因子使病毒表现得像一种不会感染人类的病毒，因为它会激活并屈服于先天免疫防御。我们的关键发现是发现，如果HCV的靶细胞具有缺陷的先天免疫系统，HCV就不需要Cyps。这表明该病毒使用Cyps来逃避先天免疫。在这里，我们的目标是确切地了解黄病毒科如何使用Cyps来逃避先天免疫保护系统。我们将确定使用的特定Cyps，并测试我们的新型Cyp抑制剂是否可以抑制复制。我们将识别Cyps靶向的病毒蛋白质，并找出Cyps在结构上对病毒蛋白质的作用，以帮助病毒隐藏。我们的药物系列区分不同的病毒，我们将研究如何区分。我们将测试活性药物靶向哪些Cyps，以解释我们所看到的抗病毒特异性。我们将研究膜网和病毒复制区室，看看当我们干扰Cyp活性时它是如何变化的。当Cyps受到干扰时，传感器是否进入复制室并被激活？我们还将研究先天免疫系统，并识别在我们发现病毒时检测病毒的活性传感器。所有这些目标都使用我们或合作者实验室中使用的经过验证的技术。我们的工作将对宿主因素如何保护病毒免受先天免疫以及如何干扰这种相互作用作为一种新的治疗或预防策略产生重要的理解。我们的目标是产生新的知识，详细介绍了先天免疫逃避的过程中的分子机制，黄病毒科和干扰的后果it. We建议，这种新的知识和展示的宿主靶向策略的易处理性将是必要的，这样的策略可以被带到临床作为有效的治疗方法。

项目成果

In Vivo Emergence of a Novel Protease Inhibitor Resistance Signature in HIV-1 Matrix.

• DOI: 10.1128/mbio.02036-20
• 发表时间: 2020-11-03
• 期刊: mBio
• 影响因子: 6.4
• 作者: Datir R;Kemp S;El Bouzidi K;Mlchocova P;Goldstein R;Breuer J;Towers GJ;Jolly C;Quiñones-Mateu ME;Dakum PS;Ndembi N;Gupta RK
• 通讯作者: Gupta RK

Disrupting HIV-1 capsid formation causes cGAS sensing of viral DNA.

• DOI: 10.15252/embj.2019103958
• 发表时间: 2020-10-15
• 期刊: The EMBO journal
• 作者: Sumner RP;Harrison L;Touizer E;Peacock TP;Spencer M;Zuliani-Alvarez L;Towers GJ
• 通讯作者: Towers GJ

ChromaClade: combined visualisation of phylogenetic and sequence data.

ChromaClade：系统发育和序列数据的组合可视化。

• DOI: 10.1186/s12862-019-1518-9
• 发表时间: 2019
• 期刊: BMC evolutionary biology
• 影响因子: 3.4
• 作者: Monit C

Synthetic PROTACs based on a depsipeptide macrocycle selectively degrade cyclophilin A and inhibit HIV-1

基于缩酚肽大环化合物的合成 PROTAC 选择性降解亲环蛋白 A 并抑制 HIV-1

• DOI: 10.21203/rs.3.rs-2639894/v1
• 发表时间: 2023
• 作者: Gathmann C

SARS-CoV-2 sensing by RIG-I and MDA5 links epithelial infection to macrophage inflammation

• DOI: 10.1101/2020.12.23.424169
• 发表时间: 2020-12
• 期刊: bioRxiv
• 作者: Lucy G. Thorne;Ann-Kathrin Reuschl;L. Zuliani-Alvarez;M. Whelan;M. Noursadeghi;C. Jolly;G. Towers