Characterization of alphavirus infection receptors

描述(申请人提供)：甲型病毒是节肢动物传播的病毒，可引起从轻度发烧到严重关节痛或致命脑炎的各种人类疾病。由于几个因素，包括它们易于隔离、长期稳定以及使用气雾剂时可能出现高发病率/死亡率，其中几种已被指定为B类精选制剂，有可能用于生物武器/生物恐怖主义。不幸的是，没有获得许可的疫苗或抗病毒药物来对抗这些感染。阻断病毒与细胞的初始相互作用是预防感染和疾病的最有效手段之一，了解病毒与感染受体的相互作用对于设计感染阻断药物至关重要。然而，对甲型病毒的受体相互作用知之甚少，因为甲型病毒尚未广泛适应细胞培养的生长。使用一种新的载体系统，我们建议同时检测代表新世界和旧世界毒株的多个非细胞适应甲型病毒的受体相互作用。在第一个目标中，我们将使用特征良好的细胞系来研究先前表征的细胞表面受体分子硫酸乙酰肝素和高亲和力的层粘连蛋白受体的利用。在第二个目标中，我们将利用我们的新型载体系统和最近在cDNA文库筛选中发现的甲型病毒受体阴性细胞系来鉴定能够介导甲型病毒感染细胞的新分子。这些实验的结果将提供对新世界和旧世界甲型病毒受体相互作用的全面了解，并为设计阻断感染的抗病毒药物提供框架。公共卫生相关性：我们的计划是使用一种新的嵌合甲型病毒复制子系统，在该系统中，将繁殖缺陷的委内瑞拉马脑炎病毒基因组包装在不同旧世界和新世界甲型病毒的结构蛋白中，以比较这些病毒低传代毒株的受体利用特征。这些比较将包括直接评估先前识别的受体(高亲和力层粘连蛋白受体)介导感染的能力，以及通过使用逆转录病毒表达文库和甲型病毒受体阴性细胞来表征新的受体。

DESCRIPTION (provided by applicant): Alphaviruses are arthropod-vectored viruses that can cause human diseases ranging from mild febrile illness to severe arthralgia or fatal encephalitis. Due to several factors including the ease of their isolation, long-term stability and potential for high morbidity/mortality when administered by aerosol, several have been designated Category B Select Agents with potential for biowarfare/bioterrorism use. Unfortunately, no licensed vaccines or antiviral medications are available to combat these infections. Interruption of the initial interactions of viruses with cells is one of the most effective means of preventing infection and disease and an understanding of virus-infection receptor interactions is vital to design of infection-blocking drugs. However, little is known about the receptor interactions of alphaviruses that have not been adapted extensively to growth in cell culture. Using a novel vector system, we propose to examine simultaneously, the receptor interactions of multiple non-cell adapted alphaviruses representative of both New World and Old World strains. In the first Aim, we will investigate the utilization of previously characterized cell surface receptor molecules heparan sulfate and the high affinity laminin receptor using well-characterized cell lines. In the second Aim we will utilize our novel vector system and a recently-identified alphavirus receptor-negative cell line in a cDNA library screen to identify new molecules that can mediate alphavirus infection of cells. The results of these experiments will provide a comprehensive understanding of the receptor interactions of New World and Old World alphaviruses and provide a framework for design of infection-blocking antiviral drugs. PUBLIC HEALTH RELEVANCE: Our plan is to use a novel chimeric alphavirus replicon system in which a propagation-defective Venezuelan equine encephalitis virus genome is packaged in the structural proteins of different Old World and New World alphaviruses to compare the receptor utilization characteristics of low passage strains of these viruses. These comparisons will include direct evaluation of the capacity of previously-identified receptors (heparan sulfate, the high affinity laminin receptor) to mediate infection as well characterization of new receptors through use of a retrovirus expression library and alphavirus receptor-negative cells.