Arenavirus entry and it's inhibition

沙粒病毒会导致高死亡率的出血热。有效疗法针对 拉沙热病毒（LASV）和阿根廷出血热病毒（Junin、JUNV）感染刻不容缓 需要解决公共卫生和国家安全问题。针对的干预策略 沙粒病毒包膜糖蛋白（GPC）为新型抗病毒药物的开发提供了合理的基础 代理。我们最近证明了 GPC 融合的胞外域之间的相互作用 亚基 (G2) 和不寻常的稳定信号肽 (SSP) 对于 GPC 介导的 pH 依赖性激活至关重要 膜融合。有趣的是，我们的初步结果强烈表明这种相互作用是有针对性的 由小分子化合物（SIGA Technologies）制成，可稳定融合前 GPC 复合物 低pH值激活，从而防止病毒进入。重要的是，原型抑制剂 ST-193 已被展示 防止豚鼠致命的 LASV 感染。我们与 SIGA 建立了合作关系 利用我们对 GPC 和这些有前途的先导化合物的知识，以确定广谱 用于临床开发的沙粒病毒治疗剂。本提案的具体目标是： 1. 识别并表征 SSP-G2 界面的分子决定因素，这些因素负责 SIGA融合抑制剂的抗病毒活性。我们将研究各个侧链对 膜融合活性及其抑制。我们将探讨序列变异在 JUNV 和 LASV 中的作用 赋予这些化合物物种特异性。细胞培养中产生的耐药分离株将 用于识别对于抗病毒活性重要的侧链。 2.表征SIGA的结构特征 有助于其抗病毒活性的抑制剂。我们将研究铅的化学衍生物 化合物来定义结构-活性关系，从而确定抑制的效力和广度。我们会 还利用四种不同化学类别的 SIGA 抑制剂的结构多样性来模拟 使用计算方法计算常见药效团。 3. 疗效评价 选定的抑制剂。优化的类药化合物将用于豚鼠症状前模型 JUNV和LASV感染以确定治疗效果。这些研究对于选择很重要 根据 FDA 两种动物规则进行 IND 申请，用于非人类灵长类动物研究的化合物 和临床开发。这项工作适合 RMRCE IRF 病毒治疗，并与 RP 3.4 相互作用。

Arenaviruses are responsible for hemorrhagic fevers with high mortality. Effective therapies against Lassa fever virus (LASV) and Argentine hemorrhagic fever virus (Junin, JUNV) infections are urgently needed to address public health and national security concerns. Intervention strategies directed at the arenavirus envelope glycoprotein (GPC) provide a rational basis for the development of novel antiviral agents. We have recently demonstrated that an interaction between the ectodomains of the GPC fusion subunit (G2) and the unusual stable signal peptide (SSP) is essential for pH-dependent activation of GPCmediated membrane fusion. Interestingly, our preliminary results strongly suggest this interaction is targeted by small-molecule compounds (SIGA Technologies) that act to stabilize the pre-fusion GPC complex against low pH activation, thereby preventing virus entry. Importantly, a prototype inhibitor ST-193 has been shown to protect against lethal LASV infection in guinea pigs. We have established a collaboration with SIGA to capitalize on our knowledge of GPC and these promising lead compounds, in order to identify a broadspectrum arenavirus therapeutic for clinical development. The specific aims of this proposal are: 1. To identify and characterize molecular determinants of the SSP-G2 interface that are responsible for the antiviral activity of SIGA fusion inhibitors. We will examine the contributions of individual sidechains to membrane-fusion activity and its inhibition. We will explore the role of sequence variation in JUNV and LASV in imparting species specificity to these compounds. Drug-resistant isolates derived in cell culture will be used to identify sidechains important for antiviral activity. 2. To characterize structural features of SIGA inhibitors that contribute to their antiviral activity. We will investigate chemical derivatives of lead compounds to define structure-activity relationships that determine potency and breadth of inhibition. We will also capitalize on the structural diversity of four distinct chemical classes of SIGA inhibitors to model a common pharmacophore using computational methods. 3. To evaluate the therapeutic efficacy of selected inhibitors. Optimized, drug-like compounds will be used in guinea pig models of pre-symptomatic JUNV and LASV infection to determine therapeutic efficacy. These studies will be important in the selection of a compound for non-human primate studies in accordance with the FDA Two-Animal Rule for IND filing and clinical development. This work fits within the RMRCE IRF-Viral Therapeutics, and interacts with RP 3.4.