The Innate Immune Response in the Marmoset Model of GBV-B Infections: A Surrogate

GBV-B 感染狨猴模型中的先天免疫反应：替代

• 批准号: 8676647
• 负责人: Robert E LANFORD
• 金额: $ 55.27万
• 依托单位: TEXAS BIOMEDICAL RESEARCH INSTITUTE
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-07-15 至 2016-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8676647
• 关键词: Address; Affect; Animal Model; Area; Biology; Callithrix; Cells; Characteristics; Chronic; Cirrhosis; Collaborations; Data; Dendritic Cells; Development; Disease Progression; Event; Failure; Feedback; GB virus B; Gene Expression; Gene Targeting; Genes; Genetic Polymorphism; Hepatitis; Hepatitis C; Hepatitis C virus; Hepatocyte; IFNAR1 gene; IRF3 gene; Immune response; Immune system; In Vitro; Individual; Infection; Interferons; Kinetics; Lead; Liver; Malignant neoplasm of liver; MicroRNAs; Modeling; Mus; Oligonucleotides; Outcome; Pan Genus; Pathway interactions; Patients; Peptide Hydrolases; Pharmaceutical Preparations; Phenotype; Play; Population; Primates; Production; Research; Research Project Grants; Role; Saguinus; Series; Source; Stimulus; System; TLR3 gene; TLR7 gene; Technology; Viral; Viral Load result; Viremia; Virus; Virus Activation; Virus Diseases; in vivo; innovation; locked nucleic acid; man; nonhuman primate; novel strategies; receptor; response; sensor; success; tissue culture; viral RNA

DESCRIPTION (provided by applicant): Hepatitis C virus infections affect approximately 2% of the population and often progress to cirrhosis and liver cancer. Some of the characteristics associated with a failed adaptive immune response in chronic infection have been identified, yet the events that precede and determine the failed immune response are less clear and may involve the innate immune response. Research on HCV has been impeded by the lack of a small animal model. In this proposal, we will use GBV-B infected marmosets in an innovative approach to evaluate knockdown of a series of target genes involved in the innate immune response. GBV-B is the virus most closely related to HCV and it induces hepatitis in marmosets and tamarins. The central hypothesis of this project is that the innate immune response is essential for limiting viral spread in the liver and for orchestrating the adaptive immune response for the successful clearance of infected cells. Knockdown of critical components of the innate response may lead to extended duration of viremia and potentially persistent infections. In collaboration with Santaris Pharma, we recently demonstrated the ability of systemically administered LNA (locked nucleic acid) oligos to knockdown genes in a primate model; the knockdown of microRNA-122 in chimpanzees effectively reduced HCV viral load. Chimpanzees are too large and expensive for use in most research projects. Marmosets are ideal for this project due to the small size and the fact that they normally clear GBV-B infection, one of the few differences from HCV. Persistent infections beyond one year have been observed, thus the capacity for persistence clearly exists. In aim 1, we will target miR122 using the same LNA antisense oligo as the Santaris drug, SPC3649. This will serve as a positive control to evaluate the kinetics and magnitude of LNA knockdown in the marmoset. In aim 2, we will knockdown IL28B and its receptor IL28RA. In man polymorphisms in IL28B are highly predictive of persistent infection with HCV, yet we have little understanding of how IL28B influences HCV infection. In aim 3, we will knockdown TLR7, the primary receptor on plasmacytoid dendritic cells sensing viral RNA and triggering IFN production. We will also knockdown BST2, the receptor that provides negative feedback to pDCs and controls IFN production. In aim 4, we will knockdown the sensors of viral RNA in the liver leading to IFN production including RIG-I, TLR3 and IRF3. Although, HCV protease subverts both these pathways, the role this plays in vivo in the spread of virus and induction of ISGs in the liver is poorly understood. Collectively, these studies will help define the role of various components of the innate immune response in viral clearance and potentially new approaches to therapies for chronic infections. In addition, persistent GBV-B infections would represent a new primate model for HCV disease progression. Furthermore, development of a primate model of targeted gene knockdown would be of great value in a number of research areas.

描述（由申请人提供）：丙型肝炎病毒感染影响了大约2％的人群，并且经常发展为肝硬化和肝癌。已经确定了与慢性感染中自适应免疫反应失败有关的某些特征，但是在免疫反应之前和确定失败的免疫反应之前的事件尚不清楚，可能涉及先天免疫反应。缺乏小型动物模型阻碍了HCV的研究。在此提案中，我们将在一种创新的方法中使用GBV-B感染的Marmosets来评估与先天免疫反应有关的一系列靶基因的敲低。 GBV-B是与HCV最密切相关的病毒，它诱导了桃花子和tamarins的肝炎。该项目的核心假设是，先天免疫反应对于限制肝脏的病毒传播至关重要，并为成功清除感染细胞而策划适应性免疫反应。先天反应的关键成分的敲低可能导致病毒血症的持续时间延长和潜在的持续感染。与Santaris Pharma合作，我们最近证明了系统施用的LNA（锁定的核酸）寡核酸寡氯乙醇在灵长类动物模型中敲低基因的能力。黑猩猩中microRNA-122的敲低有效地降低了HCV病毒载量。黑猩猩太大且昂贵，用于大多数研究项目。由于尺寸较小，而且它们通常清除GBV-B感染，这是该项目的理想选择，这是与HCV少数几个差异之一。已经观察到了一年以上的持续感染，因此显然存在持久性的能力。在AIM 1中，我们将使用与Santaris药物SPC3649相同的LNA反义寡素靶向miR122。这将是评估果果棒中LNA敲低的动力学和幅度的阳性对照。在AIM 2中，我们将击倒IL28B及其受体IL28RA。在IL28B中的人类多态性中，高度预测了HCV持续感染，但我们对IL28B如何影响HCV感染的了解很少。在AIM 3中，我们将击倒TLR7，这是浆细胞类树突状细胞上的主要受体感测病毒RNA并触发IFN产生。我们还将敲除BST2，这是对PDC和控制IFN产生的负反馈的受体。在AIM 4中，我们将击倒肝脏中病毒RNA的传感器，导致IFN产生，包括RIG-I，TLR3和IRF3。尽管HCV蛋白酶颠覆了这两种途径，但该途径在体内在病毒传播中及其在肝脏中的ISG诱导中扮演的作用很差。总的来说，这些研究将有助于定义先天免疫反应的各种组成部分在病毒清除中的作用，以及用于慢性感染疗法的新方法。此外，持续的GBV-B感染将代表HCV疾病进展的新灵长类动物模型。此外，在许多研究领域的靶向基因敲低的灵长类动物模型的发展将具有很大的价值。