Small-molecule inhibitors of HIV-induced receptor downmodulation

描述（由申请方提供）：多条证据表明，HIV感染细胞中病毒受体的下调是体内调节发病机制的基本功能。我们之前已经进行了概念验证研究，证明干扰这种功能会导致产生无法在允许细胞中复制的非感染性颗粒。在这里，我们建议筛选一个小分子库，以确定抑制剂的CD 4下调。我们将使用一个简单的筛选试验，概括生理条件和使用天然的感染靶细胞。我们提出以下目标：（1）优化HIV感染PBMC中CD 4下调的测定;（2）筛选20，000种药物样化合物的文库;和（3）验证和表征命中的效力、细胞毒性和特异性。将进行研究，以优化筛选条件，降低检测试剂盒间变异性，并进行统计分析，以设定命中识别的阈值。假阳性和伪影将在二次测定中区分，并且将基于效价、特异性和缺乏细胞毒性对真正的命中化合物进行优先级排序。将进行初步研究，以验证作用机制，并测试化合物的抗病毒活性与实验室适应的艾滋病毒株和主要分离株。在这一阶段I应用的成功被定义为一个或多个真正的铅系列的药物样化合物的里程碑识别与IC 50低于5 5 M在HIV复制试验和最小的细胞毒性（CC 50 10倍大于IC 50）。具有这些特征的先导化合物将在旨在推进这些化合物的临床前开发以支持人体试验的II期项目中针对效力、特异性和生物利用度进行优化。这些研究将构成药物发现计划的基础，该计划可能导致抗逆转录病毒药物新家族的一流药物的表征。公共卫生相关性：截至2007年底，全世界有3 300万人感染艾滋病毒。尽管在抗逆转录病毒疗法方面取得了进展，但副作用和出现对现有药物具有抗药性的病毒给艾滋病毒的治疗带来了重大问题。我们建议通过一种新的机制来鉴定和表征阻断HIV的抗逆转录病毒化合物。这些独特的化合物可用于治疗HIV感染。

DESCRIPTION (provided by applicant): Multiple lines of evidence suggest that down-modulation of the viral receptor in HIV- infected cells is an essential function modulating pathogenesis in vivo. We have previously performed proof-of-concept studies demonstrating that interference with this function results in the production of non-infectious particles unable to replicate in permissive cells. Here we propose to screen a library of small molecules to identify inhibitors of CD4 down-modulation. We will use a simple screening assay that recapitulates physiological conditions and use natural target cells of infection. We propose the following aims: (1) to optimize an assay for CD4 down-modulation in HIV-infected PBMC; (2) to screen a library of 20,000 drug-like compounds, and; (3) to validate and characterize the potency, cytotoxicity and specificity of hits. Studies will be implemented to optimize screening conditions, reduce assay-to-assay variability and perform statistical analysis to set thresholds for hit identification. False positives and artifacts will be discriminated in secondary assays, and true hit compounds will be prioritized based on potency, specificity, and lack of cytotoxicity. Preliminary studies will be performed to validate the mechanism of action and test the compounds antiviral activity with laboratory adapted HIV strains and primary isolates. Success in this Phase I application is defined as the milestone identification of one or more bona fide lead series of drug-like compounds with IC50s below 5 5M in HIV replication assays and minimal cytotoxicity (CC50 10-fold greater than IC50). Lead compounds with these profiles will be optimized for potency, specificity and bioavailability in a Phase II project aimed at advancing the preclinical development of these compounds to support human trials. These studies will constitute the foundation of a drug discovery program that may result in the characterization of first-in-class drugs of a novel family of antiretrovirals. PUBLIC HEALTH RELEVANCE: As of the end of 2007, 33 million people worldwide are infected with HIV. Despite advances in antiretroviral therapies, side-effects and the emergence of viruses resistant to currently available drugs pose important problems for the treatment of HIV. We propose to identify and characterize antiretroviral compounds that block HIV through a novel mechanism. These unique compounds could be used for the treatment of HIV infection.