Structural and functional characterization of the chemokine enhancing activity ofvaricella zoster virus (VZV) glycoprotein C

水痘带状疱疹病毒 (VZV) 糖蛋白 C 趋化因子增强活性的结构和功能表征

• 批准号: 405772731
• 负责人: Professor Dr. Thomas Krey
• 金额: --
• 依托单位: Institut für Virologie
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2018
• 资助国家: 德国
• 起止时间: 2017-12-31 至 2021-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/405772731?language=en
• 关键词: Structural; functional; characterization; chemokine; enhancing

Varicella zoster virus (VZV) is a highly prevalent human pathogen that establishes latency in peripheral neurons. VZV causes varicella during primary infection and zoster following reactivation. Zoster is characterized by acute pain and may be followed by post herpetic neuralgia (PHN), the second most common type of neuropathic pain worldwide. Despite the existence of licensed vaccines, VZV associated pain still represents a major health problem that causes an important economic burden. Moreover, VZV can also cause pathologies associated with high mortality and morbidity such as encephalitis and vasculitis when infecting the central nervous system.During natural infection VZV productively infects leukocytes and this infection event is essential for VZV spread throughout the host to the skin and neurons and also for subsequent pathogenesis. Leukocyte migration to the site of infection is orchestrated by chemokines and several viruses express viral chemokine binding proteins (vCKBP) to modulate chemokine activity. We have recently shown that VZV glycoprotein C (gC) is a vCKBP that enhances chemokine activity resulting in increased leukocyte migration - a phenotype that likely contributes to VZV spread, in contrast to the majority of vCKBP that inhibit leukocyte migration. Crystal structures have been reported for inhibitory vCKBP in complex with chemokines, but no such structural information is available for enhancing vCKBP. Finally, chemokines and viral proteins that interact with the chemokine/chemokine receptor pair induce pain. Therefore, in view of its chemokine-enhancing activity it is plausible to assume that gC plays an important role in VZV associated pain.The goal of this project is to further investigate the role of VZV gC in viral pathogenesis and in particular in the development of VZV associated pain. For this purpose, we will employ a combination of protein biochemistry and cell biology approaches. We will first set out to crystallize the minimal functionally-active soluble gC ectodomain alone and in complex with a chemokine and determine its X-ray structure(s). As glycoproteins are often difficult to crystallize and antibody fragments often facilitate crystallization in such difficult cases (i.e., they serve as "crystallization chaperones"), we will generate an antibody library targeting gC. In parallel, we will determine the mechanistic role of gC by analyzing its impact on chemokine receptor usage, clustering and signalling. Eventually, we will investigate the role of gC in the development of chemokine-mediated pain using an animal model and α-gC antibodies targeting the gC-chemokine interaction as specific control. Our results will contribute to understanding of the differences between inhibitory and enhancing vCKBP, to determine the role of gC in VZV pathogenesis and pave the way for novel therapeutic approaches to inhibit VZV spread and to combat VZV associated pain.

水痘带状疱疹病毒（VZV）是一种高度流行的人类病原体，在外周神经元中建立潜伏期。VZV在初次感染期间引起水痘，并在重新激活后引起带状疱疹。带状疱疹的特征是急性疼痛，随后可能出现疱疹后神经痛（PHN），这是全球第二种最常见的神经性疼痛。尽管存在许可的疫苗，VZV相关的疼痛仍然是一个主要的健康问题，导致重要的经济负担。此外，VZV感染中枢神经系统时，还可引起与高死亡率和发病率相关的病理，如脑炎和血管炎，在自然感染过程中，VZV可有效地感染白细胞，这种感染事件对于VZV在整个宿主中扩散到皮肤和神经元以及随后的发病机制是必不可少的。白细胞迁移到感染部位是由趋化因子协调的，并且几种病毒表达病毒趋化因子结合蛋白（vCKBP）以调节趋化因子活性。我们最近已经表明，VZV糖蛋白C（gC）是一种vCKBP，增强趋化因子活性，导致白细胞迁移增加-一种可能有助于VZV传播的表型，而大多数vCKBP抑制白细胞迁移。已经报道了与趋化因子复合的抑制性vCKBP的晶体结构，但是没有这样的结构信息可用于增强vCKBP。最后，与趋化因子/趋化因子受体对相互作用的趋化因子和病毒蛋白诱导疼痛。因此，鉴于其趋化因子增强活性，它是合理的假设，gC在VZV相关pain.The的目标是进一步研究VZV gC在病毒发病机制中的作用，特别是在VZV相关的疼痛的发展中起着重要的作用。为此，我们将采用蛋白质生物化学和细胞生物学方法的结合。我们将首先着手使最小功能活性可溶性gC胞外域单独结晶以及与趋化因子复合结晶，并确定其X射线结构。由于糖蛋白通常难以结晶并且抗体片段通常在这种困难的情况下促进结晶（即，它们充当“结晶分子伴侣”），我们将产生靶向gC的抗体文库。同时，我们将通过分析其对趋化因子受体使用、聚集和信号传导的影响来确定gC的机制作用。最后，我们将通过动物模型和靶向gC-趋化因子相互作用的α-gC抗体作为特异性对照，研究gC在趋化因子介导的疼痛发生中的作用，为理解vCKBP的抑制和增强作用之间的差异，明确gC在VZV发病机制中的作用，为抑制VZV传播和对抗VZV相关疼痛的新治疗方法奠定基础。