Heat Stable Filoviral Diagnostics

热稳定丝病毒诊断

• 批准号: 7472837
• 负责人: ANDREW HAYHURST
• 金额: $ 25.65万
• 依托单位: TEXAS BIOMEDICAL RESEARCH INSTITUTE
• 依托单位国家: 美国
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-02-15 至 2010-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7472837
• 关键词: Africa; Antibodies; Antigens; Biological; Biological Assay; Bioterrorism; Cold Chains; Communities; Complement; Country; Data; Democratic Republic of the Congo; Detection; Development; Diagnosis; Diagnostic; Diagnostic tests; Disease; Disease Outbreaks; Disruption; Ebola virus; Environment; Epitopes; Filovirus; Force of Gravity; Frankfurt-Marburg Syndrome Virus; Heating; High temperature of physical object; Immunoassay; Immunoglobulins; Individual; Ivory Coast; Life; Llama; Methods; Molecular; Nucleic Acids; Performance; Phage Display; Proteins; Public Health; Quarantine; RNA Viruses; Rate; Reagent; Refrigeration; Reporter; Resources; Reston; Risk; Route; Sampling; Sensitivity and Specificity; Serum; Shipping; Ships; Site; Sudan; System; Temperature; Testing; Therapeutic; Vaccines; Viral Antigens; Viral Hemorrhagic Fevers; Virus; antigen binding; assay development; base; coping; cross reactivity; design; disease transmission; extreme temperature; improved; molecular recognition; mortality; nonhuman primate; novel; portability; rapid diagnosis; response; thermostability; transmission process

DESCRIPTION (provided by applicant): The broad long-term objectives of this proposal are to develop heat stable immunoassay reagents for Marburg and Ebola viruses and begin elucidating the molecular requirements for effective antigen capture assay performance. Both filoviruses continue to cause devastating outbreaks of hemorrhagic fever in Africa and threaten non-endemic countries, through the return of infected travelers, the importation of infected non-human primates and the threat of bioterrorism. The absence of vaccines and effective therapeutics means that rapid diagnosis is essential to contain an outbreak wherever it may occur. Current diagnostics are limited in terms of durability, portability and availability especially in resource poor settings and our aim is to augment these capabilities to help safeguard public health. We hypothesize that carefully chosen llama single domain antibody (sdAb) proteins specific for each of the five filovirus species will enable the assembly of rapid, accurate yet robust diagnostics. We base this hypothesis upon our studies that: 1. sdAbs selected to diverse antigens retain specific antigen binding activity when exposed to high temperatures unlike conventional immunoglobulins and 2. sdAbs selected to Marburg virus enable rapid antigen capture assays to be established that match nucleic acid based detection methods in terms of sensitivity and specificity. Our specific aims are to: 1. Characterize pre-existing sdAbs that have been selected against Marburg virus for their thermostability and requirements for molecular recognition; 2. Characterize sdAbs selected on Ebola Zaire, Sudan, Ivory Coast and Reston to determine if the degree of assay sensitivity-specificity is conserved and if the sdAbs are thermostable; 3. Begin to rationalize the molecular recognition of the Ebola sdAb and, in concert with the Marburg sdAb data, understand the rules and requirements for effective antigen capture assay development. These studies will guide the way to formulating inexpensive, simple yet ultrasensitive filoviral diagnostics with potentially infinite shelf lives even in the absence of refrigeration. PUBLIC HEALTH RELEVANCE: The filoviruses Marburg and Ebola continue to cause unpredictable outbreaks of transmissible and highly lethal hemorrhagic fevers in Africa. Other countries are also at risk through the importation of infected non-human primates, the return of infected tourists from endemic regions, and the threat of bioterrorism. Since no vaccines or therapeutics are currently available for these viruses, it is imperative to rapidly identify infected individuals on-site and quarantine them to reduce disease transmission. We aim to develop novel, durable antibodies specific for filoviral species to aid the development of inexpensive, rapid diagnostic tests to meet this urgent need. We also wish to study the mechanism of how these novel anti-filoviral antibodies can equal nucleic acid based detection limits to understand how to formulate improved virus antigen capture assays.

描述（由申请人提供）：该提案的广泛长期目标是开发针对马尔堡病毒和埃博拉病毒的热稳定免疫测定试剂，并开始阐明有效抗原捕获测定性能的分子要求。这两种丝状病毒继续在非洲造成毁灭性的出血热疫情，并通过受感染旅行者的回返、受感染的非人类灵长类动物的输入以及生物恐怖主义的威胁，威胁非流行国家。由于缺乏疫苗和有效的治疗方法，无论在哪里发生疫情，快速诊断对于遏制疫情都至关重要。当前的诊断在耐用性、便携性和可用性方面受到限制，特别是在资源匮乏的环境中，我们的目标是增强这些能力以帮助保障公众健康。我们假设，精心挑选的对五种丝状病毒中的每一种具有特异性的美洲驼单域抗体 (sdAb) 蛋白将能够实现快速、准确且稳健的诊断。我们的这一假设基于我们的研究：1. 与传统免疫球蛋白不同，针对不同抗原选择的 sdAb 在暴露于高温时保留特异性抗原结合活性；2. 针对马尔堡病毒选择的 sdAb 能够建立与基于核酸相匹配的快速抗原捕获测定法。检测方法的敏感性和特异性。我们的具体目标是： 1. 表征针对马尔堡病毒而选择的现有 sdAb 的热稳定性和分子识别要求； 2. 对埃博拉扎伊尔、苏丹、科特迪瓦和雷斯顿选择的 sdAb 进行表征，以确定测定敏感性-特异性的程度是否保守以及 sdAb 是否具有热稳定性； 3. 开始合理化埃博拉 sdAb 的分子识别，并结合马尔堡 sdAb 数据，了解有效抗原捕获测定开发的规则和要求。这些研究将指导制定廉价、简单但超灵敏的丝状病毒诊断方法，即使在没有冷藏的情况下也可能具有无限的保质期。公共卫生相关性：马尔堡病毒和埃博拉病毒继续在非洲引发不可预测的传染性和高致命性出血热疫情。其他国家也面临着受感染的非人类灵长类动物输入、受感染游客从流行地区返回以及生物恐怖主义威胁的风险。由于目前还没有针对这些病毒的疫苗或治疗方法，因此必须在现场快速识别感染者并对其进行隔离，以减少疾病传播。我们的目标是开发针对丝状病毒物种的新型、持久的特异性抗体，以帮助开发廉价、快速的诊断测试，以满足这一迫切需求。我们还希望研究这些新型抗丝状病毒抗体如何达到基于核酸的检测限的机制，以了解如何制定改进的病毒抗原捕获测定法。