Primate Model Towards HIV Eradication Strategies

灵长类动物模型走向艾滋病毒根除策略

• 批准号: 7756368
• 负责人: THOMAS W NORTH
• 金额: $ 74.79万
• 依托单位: UNIVERSITY OF CALIFORNIA AT DAVIS
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-06-15 至 2013-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7756368
• 关键词: Animal Model; Anti-Retroviral Agents; Antiviral Agents; Antiviral Therapy; Biological Assay; Blood; CCR5 gene; CD4 Positive T Lymphocytes; Cells; Clinical; DNA; Detection; Development; Drug Combinations; Future; Goals; HIV; HIV-1; HIV-1 Reverse Transcriptase; Highly Active Antiretroviral Therapy; Human; Individual; Infection; Integrase Inhibitors; Latent Virus; Liquid substance; Macaca; Macaca mulatta; Measures; Modeling; Monitor; Organ; Outcome; Pharmaceutical Preparations; Pharmacotherapy; Plasma; Population; Primates; Protease Inhibitor; RNA; RNA-Directed DNA Polymerase; Relative (related person); Research; Residual state; Rest; Reverse Transcriptase Polymerase Chain Reaction; SIV; Sampling; T memory cell; T-Lymphocyte; Time; Tissues; Transcript; Treatment Protocols; Viral; Viral Genome; Viral load measurement; Viremia; Virus; Virus Latency; Virus Replication; analog; antiretroviral therapy; cell type; design; efavirenz; efficacy evaluation; improved; insight; macrophage; monocyte; non-nucleoside reverse transcriptase inhibitors; novel; nucleoside analog; pinacolyl methylphosphonic acid; prevent; public health relevance; success; viral DNA; viral RNA

DESCRIPTION (provided by applicant): The long-term goal of this project is to develop and evaluate strategies for eradication of HIV-1 from infected individuals. These studies will be performed with an animal model that enables comprehensive analyses of viral reservoirs and replication dynamics during HAART. This model utilizes rhesus macaques infected by a chimeric virus of SIVmac239 containing the HIV-1 reverse transcriptase (RT) in place of the SIV RT (RT-SHIV). In this model a three-drug combination that is widely used in humans [efavirenz + (-)-FTC + PMPA] mimics HAART in HIV- 1-infected humans with respect to virus load (VL) suppression and rebound upon cessation of drug therapy. In order to study eradication strategies in the RT-SHIV/macaque model, we have developed a sensitive VL assay with a limit of detection of 1-2 copies of viral RNA (vRNA) per ml of plasma, and have also developed sensitive RT-PCR and PCR assays to measure vRNA and viral DNA (vDNA) in tissues. The goal of this project is to evaluate enhanced HAART in combinations that may more fully suppress plasma and tissue VLs to levels below detection with our sensitive PCR assays. Because a potential limitation of current antiretroviral therapy is access of drugs to key reservoir tissues, we will also determine levels of drugs in target tissues and use that information to optimize drug regimens. In addition to virological endpoints, the impact of these drug combinations will be evaluated in RT-SHIV-infected resting CD4+ lymphocyte populations. Importantly, the highly manipulatable RT-SHIV/macaque model enables assessment of potential clinical impact by determining effects on delay or reduction of viral rebound upon cessation of therapy. The drug combinations we propose are designed to evaluate: i) optimization of DNA chain termination with combinations of four potent nucleoside analogs (NRTI) in combination with efavirenz (NNRTI) or an integrase inhibitor, raltegravir; ii) combinations of the most effective NRTIs with both efavirenz and raltegravir; and iii) enhancement of the most potent drug combination with a protease inhibitor or a CCR5 antagonist. The overall Hypothesis of this project is that an intensified HAART regimen has the potential to eliminate RT-SHIV from infected macaques. These studies will provide insight on the requirements for complete suppression of virus replication in tissues and specific cell types as well as in plasma. Thus, this project aims to determine whether there is a limitation to suppression of residual viremia with antiviral drug combinations and whether eradication will also require "induction" strategies for reactivation of latent virus. PUBLIC HEALTH RELEVANCE: It is likely that eradication of HIV-1 from infected individuals will require both full suppression of virus replication and the reactivation of latent virus during fully suppressive therapy. The focus of this project is elimination of residual virus replication in cells and tissues. The results will provide important information about the relative contributions of virus replication and other reactivation of latent virus to residual viremia during HAART, the relationship between drug levels and virus suppression in tissues and specific cell types, and the effect of enhanced therapy on latent reservoirs in resting CD4+ T lymphocytes. The results of this study will also contribute to future studies of strategies for eliminate the resting memory T cell reservoir of latent HIV-1. The success of such induction strategies will likely be dependent on the ability of fully suppressive HAART to prevent replication of reactivated virus.

描述（由申请人提供）：该项目的长期目标是制定和评估从感染者中根除HIV-1的策略。这些研究将使用动物模型进行，该模型能够全面分析HAART期间的病毒储库和复制动力学。该模型利用被含有HIV-1逆转录酶（RT）代替SIV RT（RT-SHIV）的SIVmac 239嵌合病毒感染的恒河猴。在该模型中，广泛用于人类的三种药物组合[依法韦仑+（-）-FTC + PMPA]在病毒载量（VL）抑制和药物治疗停止后反弹方面模拟HIV- 1感染者的HAART。为了研究RT-SHIV/猕猴模型中的根除策略，我们开发了一种灵敏的VL测定法，其检测限为每ml血浆中1-2个病毒RNA（vRNA）拷贝，还开发了灵敏的RT-PCR和PCR测定法来测量组织中的vRNA和病毒DNA（vDNA）。该项目的目标是评估增强的HAART组合，这些组合可以更充分地将血浆和组织VL抑制到低于我们灵敏的PCR检测方法检测的水平。由于目前抗逆转录病毒治疗的一个潜在限制是药物进入关键储库组织，我们还将确定靶组织中的药物水平，并利用这些信息优化药物治疗方案。除病毒学终点外，还将在RT-SHIV感染的静息CD 4+淋巴细胞群中评价这些药物组合的影响。重要的是，高度可操作的RT-SHIV/猕猴模型能够通过确定对治疗停止后病毒反弹延迟或减少的影响来评估潜在的临床影响。我们提出的药物组合旨在评估：i）四种有效核苷类似物（NRTI）与依法韦仑（NNRTI）或整合酶抑制剂雷特格韦组合的DNA链终止优化; ii）最有效的NRTI与依法韦仑和雷特格韦的组合; iii）与蛋白酶抑制剂或CCR 5拮抗剂的最有效药物组合的增强。该项目的总体假设是，强化的HAART方案有可能从受感染的猕猴中消除RT-SHIV。这些研究将提供关于完全抑制组织和特定细胞类型以及血浆中病毒复制的要求的见解。因此，本项目旨在确定抗病毒药物组合抑制残留病毒血症是否存在局限性，以及根除是否还需要“诱导”策略以重新激活潜伏病毒。公共卫生相关性：从感染个体中根除HIV-1可能需要完全抑制病毒复制和在完全抑制治疗期间重新激活潜伏病毒。该项目的重点是消除细胞和组织中残留的病毒复制。这些结果将提供重要的信息，相对贡献的病毒复制和其他再活化的潜伏病毒残留病毒血症在HAART，药物水平和病毒抑制之间的关系，在组织和特定的细胞类型，以及增强治疗的作用，潜伏水库休息的CD 4 + T淋巴细胞。这项研究的结果也将有助于未来的研究策略，消除潜伏的HIV-1的静息记忆T细胞库。这种诱导策略的成功可能取决于完全抑制性HAART防止再活化病毒复制的能力。