Host Genetic Factors to Combat Lassa Hemorrhagic Fever

对抗拉沙出血热的宿主遗传因素

基本信息

批准号：
8711266
负责人：
MICHAEL B OLDSTONE
金额：
$ 47.38万
依托单位：
SCRIPPS RESEARCH INSTITUTE, THE
依托单位国家：
美国
项目类别：
财政年份：
2013
资助国家：
美国
起止时间：
2013-08-01 至 2017-07-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8711266
关键词：
Affect Africa African Air Alleles Alternative Splicing Animal Model Applications Grants Area Arenavirus Binding Biological Assay Biological Warfare Categories Cell Line Cells Cellular biology Centers for Disease Control and Prevention (U.S.)Cessation of life Code Complex Defect Dendritic Cells Disease Enzymes Europe Evolution Fibroblasts Fruit Functional RNA Generations Genes Genetic Genetic Markers Genetic Polymorphism Genetic Transcription Genetic Variation Grant Hand Heart Human ITGAX gene Immigrant Immune response Immune system Implant In Vitro Individual Infection Laboratories Lassa fever virus Learning Letters Life Link Lymphocytic choriomeningitis virus Measures Mediating Messenger RNA Molecular Molecular Biology Molecular Conformation Mus Mutant Strains Mice Mutate Mutation Natural Selections Nigeria Persons Play Population Post-Translational Protein Processing Predisposition Public Health RNA Interference RNA Splicing Receptor Cell Recombinants Recovery Reporting Resistance Role Sampling Serum Shapes Sierra Leone Skeletal Muscle Source Surrogate Markers Surveys Survivors Technology Testing Tissues Transgenes Transgenic Mice United States Viral Viral Hemorrhagic Fevers Viremia Virus Virus Diseases Virus Receptors Virus Replication Western Africa alpha Dystroglycan biosafety level 4 facility combat design genetic selection genome sequencing glycosylation glycosyltransferase in vitro testing in vivo killings mRNA Expression microbial monocyte mouse model mutant novel prevent promoter public health relevance receptor recombinant virus sugar virus pathogenesis weapons

项目摘要

DESCRIPTION (provided by applicant): This grant focuses on arenavirus pathogenesis (how viruses cause disease) and why during infection some hosts become severely ill and die while others remain relatively unscathed. Lessons learned from lymphocytic choriomeningitis virus (LCMV) are applied to Lassa fever virus (LASV). LASV infects over 300,000 individuals per year resulting in over 20,000 deaths. LASV has been transported by travelers from Western Africa to the USA. Its potential as a weapon of biowarfare is a source of national concern. LASV is placed on the Category A list of microbial agents. My laboratory identified alpha-dystroglycan (¿-DG) as the host cell receptor for LCMV and LASV and demonstrated preferential localization of ¿-DG on dendritic cells (DCs). We then showed that post- translational modification of ¿-DG by the glycosyltransferase LARGE is absolutely critical for the functional maturation of ¿-DG as a receptor for LASV and LCMV binding, entry and replication. P. Sabeti and colleagues found that mutations in LARGE were common in West African populations of Nigeria and Sierra Leone where LASV infection is endemic, but absent in those populations in West Africa where LASV is not endemic. Polymorphisms of the LARGE allele are present in about 35% of the population where LASV is endemic with about 45% of individuals heterozygous and 16% homozygous for it. Mutations in LARGE are found in LASV survivors. Since high viremia (> 9 logs of plaque forming units [PFU/ml of sera]) is routinely associated with signs of severe LASV infection and death, whereas lower viremia (< 8 logs of PFU/ml or less) with recovery, and the ¿-DG/LARGE complex controls LASV entry and subsequent replication, it is likely that mutations in LARGE shape evolution by favoring survival of the host against this virus. Limiting the amount of virus made provides the host's immune system a window of opportunity to mount an effective anti-LASV immune response thereby preventing severe disease and promoting virus clearance. This grant's purpose is to determine if LARGE mutations are responsible for survival to LASV infection. We will assay cells permissive to LASV infection (DCs/monocytes) that contain LARGE mutations in a functional LARGE enzyme assay, and for virus binding, entry and replication using a LASV Gp/LCMV recombinant virus. The recombinant virus can be used in BSL/2 laboratory and has been shown to bind, enter and replicate in permissive human and mouse cells. Thereafter those DCs and monocytes from individuals having LARGE mutations and displaying altered LASV binding, entry or replication or enzymatic activity will be tested at CDC with wtLASV. The fruits of these studies provide the opportunity to identify forces shaping human evolution in that individuals possessing LARGE mutant alleles are likely selected for resistance to LASV. Further, these studies may also identify surrogate markers to classify susceptible or resistant individuals to this viral infection.

描述（由申请人提供）：这项资助的重点是沙粒病毒发病机制（病毒如何引起疾病）以及为什么在感染过程中一些宿主会严重患病并死亡，而其他宿主则相对毫发无伤。从淋巴细胞脉络膜脑膜炎病毒（LCMV）中吸取的经验教训适用于拉沙热。 LASV 病毒每年感染超过 300,000 人，导致 20,000 多人死亡。它作为生物战武器的潜力引起了全国关注，我的实验室将 α-肌营养不良聚糖 (¿-DG) 确定为 LCMV 和 LASV 的宿主细胞受体。展示了 ¿ 的优先本地化-DG 对树突状细胞（DC）的影响随后我们证明了 ¿糖基转移酶 LARGE 产生的 -DG 对于 ¿ 的功能成熟绝对至关重要-DG 作为 LASV 和 LCMV 结合、进入和复制的受体，P. Sabeti 及其同事发现 LARGE 突变在 LASV 感染流行的西非人群中很常见，但在西非这些人群中不存在。其中 LASV 不是地方性的，大约 35% 的人群中存在 LARGE 等位基因的多态性，而 LASV 是地方性的，其中大约 45% 的个体是杂合的，16% 的个体是纯合的。在 LASV 幸存者中发现了 LARGE 突变，因为高病毒血症（> 9 个噬菌斑形成单位 [PFU/ml 血清]）通常与严重 LASV 感染和死亡的迹象相关，而较低的病毒血症（< 8 个噬菌斑形成单位 [PFU/ml 血清]）通常与严重 LASV 感染和死亡的迹象相关。 PFU/ml 或更少）与恢复，以及 ¿ -DG/LARGE 复合物控制 LASV 的进入和随后的复制，LARGE 中的突变很可能通过有利于宿主针对这种病毒的生存而形成进化，从而为宿主的免疫系统提供了一个机会之窗，以建立有效的病毒。抗 LASV 免疫反应严重疾病并促进病毒清除。这项资助的目的是确定大突变是否导致 LASV 感染的存活。我们将检测包含 LASV 感染的细胞（DC/单核细胞）。功能性 LARGE 酶测定中的 LARGE 突变，以及使用 LASV Gp/LCMV 重组病毒进行病毒结合、进入和复制。重组病毒可用于 BSL/2 实验室，并已被证明可以在允许的人类中结合、进入和复制。此后，来自具有较大突变并表现出改变的 LASV 结合、进入或复制或酶活性的个体的 DC 和单核细胞将在 CDC 中用 wtLASV 进行测试。提供了确定影响人类进化的力量的机会，因为具有大突变等位基因的个体可能被选择对 LASV 具有抵抗力。此外，这些研究还可以确定替代标记来对这种病毒感染的易感性或抵抗性个体进行分类。