Basic and Comparative Studies of CCR5 Inhibition to Prevent HIV Transmission

抑制 CCR5 预防 HIV 传播的基础和比较研究

• 批准号: 7391001
• 负责人: MICHAEL MARCEL LEDERMAN
• 金额: $ 158.58万
• 依托单位: CASE WESTERN RESERVE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-06-06 至 2011-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7391001
• 关键词: Basic; Comparative; Studies; CCR5; Inhibition; Basic; Comparative; Studies; CCR5; Inhibition

DESCRIPTION (provided by applicant): Growth of the HIV pandemic that is largely transmitted through sex, gives a compelling need to develop strategies to limit its explosive spread. It is clear that there is not yet a single strategy that will accomplish this. Thus it is vital to continue research at multiple levels and disciplines to develop potentially useful prevention strategies that may provide attenuation of HIV transmission. We have assembled an outstanding team who propose three interlocking projects that will provide new information critical to the development of microbicide strategies in general, to strategies targeting CCR5 and to developing a better understanding of the human and non-human primate female genital tract. We have been developing RANTES analogues that block OCRS and inhibit HIV replication at subnanomolar concentrations. Our first lead, PSC-RANTES has protected all 10 of 10 rhesus macaques challenged with SHIV 162P3 thus providing the most potent protection against SHIV of any agent reported to date. Limitations to this strategy include an incomplete understanding of the fundamental mechanisms whereby different RANTES analogues block HIV access to CCR5, their potential agonist activity that may result in inflammation, a limited durability of protection, the costs of synthesis and finally an incomplete understanding of the similarities and differences between the human and rhesus female genital tracts that may limit generalization of findings in the one to application in the other. Here, we propose to address each of these issues, with three projects: Project 1: Defining inhibitory Mechanisms of Novel CCRS-targeted Microbicide Candidates - As we have developed several classes of RANTES analogues with discreetly different effects on CCR5 localization and signaling, these studies are designed to explore the cellular and molecular interactions that underlie the activities of these analogues. Project 2: Comparative gynecologic studies in humans and rhesus macaques - This will focus on defining the similarities and differences between the cervicovaginal epithelium of humans and non-human primates to establish the degree to which findings in these animals can be transposed to projections of activity in humans. Thus, the results of this work will be critical both to the development of RANTES analogues as well as to all other strategies for topical prevention of HIV transmission. Project 3: Developing RANTES analogues as topical strategies to prevent HIV transmission: will explore agonist activities of different analogues to identify inhibitory pathways of potential inflammatory effects, will examine synergistic activities of HIV inhibitor combinations and novel hydrogel formulations to enhance the durability of protection and will develop methods for large scale GMP synthesis of fully recombinant agents that will permit affordable application of this strategy. An experienced Administrative Core provides infrastructural support for these projects as well as statistical expertise for analyses of their results. PROJECT 1: Defining Inhibitory Mechanisms of Novel CCRS-targeted Microbicide Candidates, Mosier, D. PROJECT 1 DESCRIPTION (provided by applicant): The goal of Project 1 is to define the mechanism of action of three new chemokine analogues with potent activity in blocking HIV-1 entry via CCR5. These fully recombinant molecules display three distinct activity profiles: (group I) CCR5 blockade without signaling activity or receptor internalization; (group II), CCR5 rapid internalization with signaling activity; and (group III), moderate CCR5 internalization and blockade without signaling activity. These new molecules have significant potential advantages in terms of safety and cost of production over current inhibitors such as PSC-RANTES, but further improvements on these candidate microbicides requires more detailed knowledge of their mechanisms of action. We will define the route to intracellular sequestration for group II molecules, and compare with that of the group III molecules. We will examine a number of hypotheses to explain prolonged antiviral activity in the absence of intracellular receptor sequestration (group I) or with moderate internalization (group III), including changes in CCR5 dimer formation, altered receptor localization in the membrane, allosteric effects, and receptor internalization independent of G-protein-linked signaling. We will also examine the impact of CCR5, CCL5, and CCL3L1 genetic polymorphisms on CCR5 protein synthesis and turnover rate. These studies are designed to investigate variability in the susceptibility of primary target cells from normal human donors to each of the new inhibitors. We will also use a panel of mutant CCR5 molecules to examine structural correlates of activity. We will use this information on mechanism and target cell variability to develop new molecules with even better activity profiles, and we will perform coordinated experiments with other projects in this Program to relate our findings in cell-based models to the effects of current and new CCR5 inhibitors in tissue explant and whole animal models. This approach will generate better and safer CCR5 inhibitors that can be produced on a scale suitable for stopping the spread of HIV/AIDS in the most-impacted areas.

描述（由申请人提供）：在很大程度上通过性传播的艾滋病毒大流行的生长给出了迫切需要制定策略来限制其爆炸性传播的策略。显然，尚无单一策略可以实现这一目标。因此，继续在多个层次和学科上进行研究以制定可能提供艾滋病毒传播衰减的潜在有用的预防策略至关重要。我们组建了一个杰出的团队，该团队提出了三个互锁项目，这些项目将为一般的杀菌剂策略，针对CCR5的策略提供至关重要的新信息，并对人类和非人类灵长类动物女性生殖道有更好的了解。我们一直在开发类似物，以阻断OCR并抑制亚诺摩尔浓度下的HIV复制。我们的第一个领先优势PSC-Rantes保护了SHIV 162p3挑战的10个恒河猕猴中的所有10个，从而为迄今为止报道的任何代理商提供了最有效的SHIV保护。该策略的局限性包括对基本机制的不完全理解，在这种机制中，不同的类似物阻止了艾滋病毒对CCR5的访问，其潜在的激动剂活动可能导致炎症，有限的保护耐用性，合成的成本以及最终对人类和瑞典女性生殖器之间的相似性和差异的不完全理解，可以限制对人类生殖器之间的限制。在这里，我们建议通过三个项目解决这些问题：项目1：定义新型CCR靶向的杀微生物候选物的抑制作用机制 - 因为我们开发了几类对CCR5定位和信号谨慎影响的Rantes类似物，这些研究旨在探索细胞和分子相互作用，从而探索这些刻板的影响。项目2：人类和恒河猕猴的比较妇科研究 - 这将着重于定义人类和非人类灵长类动物的子宫颈阴道上皮之间的相似性和差异，以确定这些动物中人类发现的程度可以将其转化为活动投射的活动。因此，这项工作的结果对于rantes类似物的发展以及所有其他局部预防HIV传播的策略都至关重要。项目3：开发rantes类似物作为预防HIV传播的局部策略：将探索不同类似物的激动剂活动，以识别潜在炎症效应的抑制性途径，将检查HIV抑制剂组合和新型水文配方的协同活性，以增强保护的耐用性，并为大型GMP GGMP施加能力提供全面的策略，从而使该策略具有全面的构成能力。经验丰富的行政核心为这些项目提供了基础设施支持，以及分析其结果的统计专业知识。 项目1：定义新型CCR靶向菌心候选物的抑制作用机制，Mosier，D。 项目1描述（由申请人提供）：项目1的目的是定义三个新的趋化因子类似物的作用机理，并通过CCR5阻止HIV-1进入HIV-1。这些完全重组的分子显示出三个不同的活性曲线：（I组）CCR5阻断而没有信号活性或受体内在化； （II组），CCR5具有信号活性的快速内在化； （第三组），中等的CCR5内在化和阻塞而没有信号活性。这些新分子在安全性和生产成本方面具有显着的潜在优势，而不是当前的抑制剂，例如PSC-rantes，但是对这些候选菌皮剂的进一步改进需要对其作用机理的详细了解。我们将定义II组分子的细胞内螯合途径，并与III组分子的途径进行比较。我们将检查许多假设，以解释在没有细胞内受体固次（I组）或中度内在化（III组）的情况下，包括CCR5二聚体形成的变化，受体定位改变，膜上改变，分析性效应和受体内在化的受体定位改变了，独立于G-ProteIn信号透明的膜上。我们还将研究CCR5，CCL5和CCL3L1遗传多态性对CCR5蛋白合成和周转率的影响。这些研究旨在调查原代靶细胞从正常供体对每个新抑制剂的敏感性的变异性。我们还将使用一组突变的CCR5分子来检查活性的结构相关性。我们将使用有关机制和靶细胞变异性的此信息来开发具有更好活性曲线的新分子，我们将与该程序中的其他项目进行协调的实验，以将基于细胞模型的发现与当前和新的CCR5抑制剂在组​​织epplant和全动物模型中的影响相关联。这种方法将产生更好，更安全的CCR5抑制剂，该抑制剂可以以适合于在最受影响的地区停止艾滋病毒/艾滋病传播的尺度产生。