Rational design & optimization of new live-attenuated vaccines for alphaviral enc

合理设计

• 批准号: 7649158
• 负责人: KATHERINE D RYMAN
• 金额: $ 16.52万
• 依托单位: UNIVERSITY OF TEXAS MED BR GALVESTON
• 依托单位国家: 美国
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-03-01 至 2009-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7649158
• 关键词: Alphavirus; Antiviral Agents; Antiviral resistance; Attenuated; Attenuated Live Virus Vaccine; Categories; Dendritic Cells; Development; Disabled Persons; Eastern Equine Encephalitis Virus; Encephalitis Viruses; Equus caballus; Face; Family; Formalin; Genome; Goals; Human; Immune; Immune response; Inactivated Vaccines; Interferon-alpha; Interferon-beta; Lead; Life; Livestock; Mediating; Mus; Mutation; Pathway interactions; Population; Property; Relative (related person); Research; Residual state; Resistance; Sindbis Virus; Togaviridae; United States National Institutes of Health; Vaccine Production; Vaccine Therapy; Vaccines; Venezuelan Equine Encephalitis Virus; Viral Drug Resistance; Virulence; Virulent; Virus; attenuation; base; biodefense; design; immunogenicity; mutant; novel; pathogen; response

Eastern equine encephalitis virus (EEEV), an Alphavirus in the family Togaviridae, is classified in Category B of the NIH Priority Pathogens List, and as a high consequence livestock pathogen by the USDA because it is highly lethal for humans and equines, and because effective vaccines and therapies are lacking, EEEV. The formalin-inactivated vaccine strain of EEEV is not suitable for wide-scale human use due to poor immunogenicity and possible residual virulence. Clearly alternative strategies for vaccine production are required. Our long-term goal is to develop a live-attenuated virus vaccine with sufficient degree of attenuation to be safe for human populations. The objective of the proposed research is the rational design of attenuated strains via the selective deletion (or disabling) of innate immune evasion properties. This will be based on the hypothesis that EEEV possesses mechanism(s) to antagonize the interferon alpha/beta (IFN-a/¿) response elicited by infected dendritic cells (DCs) which can be disabled to attenuate the virus and enhance the immune response. Several key observations lead us to believe that the relative sensitivity of alphaviruses to IFN-a/¿-mediated antiviral activity is a primary determinant of virulence and attenuation. Our studies with Sindbis virus (SB) have revealed that this alphavirus with little or no ability to evade or antagonize mammalian IFN-a/¿ is extremely attenuated in mice whereas, a mousevirulent alphavirus, such as Venezuelan equine encephalitis virus (VEEV), is relatively much more resistant to the antiviral activity of IFN-a/¿. Mutants of VEEV with increased sensitivity to IFN-a/¿ are attenuated in mice. As EEEV also remains virulent in the face of a functional IFN-a/¿ response, and alphavirus virulence appears to be strongly correlated with IFN-a/¿ resistance, we hypothesize that EEEV evades and/or disables components of the IFN-a/¿ response. We propose to gain a better understanding of the way(s) in which EEEV overcomes the antiviral activity of IFN-a/¿ by comparison to SB with the goal of developing an IFN-a/¿ sensitive, live-attenuated EEEV strain by determining which IFN-a/¿-mediated pathway(s) are antagonized or evaded by EEEV. Specifically, we will (1) determine relative to SB the mechanisms by which EEEV nfection product(s) facilitate the evasion/antagonism of IFN-a/¿-mediated antiviral activity; and (2) characterize the effects of targeted mutations in the EEEV genome on antagonism/evasion of the IFN-a/pmediated response. We anticipate that these studies will allow the identification and disablement of EEEV encoded product(s) that antagonize/resist IFN-a/¿ activity. Anticipated product(s): Our long-term goal is the rational design of attenuated alphavirus strains with sufficient degree of attenuation to be safe for human populations via the selective inactivation of innate immune evasion properties.

东马脑炎病毒（EEEV）是togaviridae家族中的α病毒，分为B类 NIH优先病原体列表，作为USDA的高后果牲畜病原体，因为它是 对于人类和马来说，高度致命，并且由于缺乏有效的疫苗和疗法，所以EEEV。 福尔马林灭活的EEEV疫苗应变不适合大规模的人类使用，因为较差 免疫原性和可能的​​残留病毒。显然，疫苗生产的替代策略是 必需的。我们的长期目标是开发具有足够程度的活体衰减病毒疫苗 衰减对人口的安全。拟议研究的目的是理性设计 通过选择性删除（或禁用）先天免疫进化特性的衰减菌株的菌株。这会 基于以下假设：EEEV具有拮抗干扰素的机制 受感染的树突细胞（DC）引起的alpha/beta（IFN-a/¿）反应，可以禁用 减轻病毒并增强免疫响应。几个关键观察使我们相信 字母对IFN -A/®抗病毒活性的相对灵敏度是主要的确定 病毒和衰减。我们对信德比斯病毒（SB）的研究表明，这种α病毒很少或很少 在小鼠中，没有能力逃避或拮抗哺乳动物IFN-A/¿ α病毒，例如委内瑞拉马脑炎病毒（VEEV），耐药性相对较高 IFN-A/¿的抗病毒活性。 VEEV的突变体对IFN-A/€的敏感性增加被衰减 老鼠。由于EEEV在功能性IFN-A/€方面也保持着毒气，并且α病毒病毒 似乎与IFN-A/»抵抗密切相关，我们假设EEEV逃避和/或禁用 IFN-A/¿响应的组成部分。我们建议更好地了解 与SB相比，EEEV克服了IFN-A/¿的抗病毒活性，目的是开发IFN-A/¿ 通过确定哪种IFN-A/®介导的途径是敏感的，实时衰减的EEEV菌株 或由EEEV逃避。具体而言，我们将（1）确定相对于SB的EEEV的机制 NFection产物促进IFN -A/®介导的抗病毒活性的逃避/拮抗作用； （2） 表征靶向突变在EEEV基因组中对IFN-A/PSDIDED的拮抗/逃避的影响 回复。我们预计这些研究将允许识别和禁用EEEV 拮抗/抵抗IFN-A/活动的编码产品。预期产品：我们的长期目标是 衰减的α病毒菌株的合理设计具有足够程度的衰减，以对人类安全 通过选择性灭活先天免疫进化特性的种群。