Broad-range Inhibitors of Human Immunodeficiency Virus Entry

描述（由申请人提供）：人类免疫缺陷病毒（HIV-1）是获得性免疫缺陷综合征（AIDS）的病原。全球艾滋病毒-1大流行（约3500万人感染）每年有200万至300万新感染。要改变这一流行病的发展趋势，就必须预防艾滋病毒-1的传播，其中大多数是通过性行为传播的。在缺乏有效疫苗的情况下，迫切需要阻断HIV-1性传播的方式。最近，对特定抗逆转录病毒药物的使用进行了调查，并显示可部分保护高危性伴侣免受HIV-1感染。然而，部分疗效、药物副作用和耐药病毒的出现限制了这些特殊药物作为预防措施的普遍适用性。可以作为局部杀微生物剂的新型广泛活性抗病毒药物可以弥补这些缺陷。介导病毒进入靶细胞的HIV-1包膜糖蛋白（Envs）是这类预防药物的有吸引力的靶标。HIV-1 Envs暴露在病毒表面，可被水溶性抑制剂接触，并且在每个病毒粒子上数量较少。用作杀微生物剂的Env抑制剂不需要被宿主细胞全身吸收或吸收，从而限制了潜在的毒性。Env的保守元件介导受体结合、构象改变和膜融合，提供了几个潜在的抑制靶点。尽管已经确定了一些HIV-1进入抑制剂，但耐药HIV-1变体要么自然存在，要么在治疗过程中发展。我们设计了一种筛选策略，以确定新的广泛的HIV-1进入抑制剂。在我们的筛选实验中，HIV-1的Env功能导致表达Env的细胞与表达病毒受体的细胞融合。这种细胞-细胞融合试验和特异性控制试验将在NIH小分子文库的初级筛选中并行使用。排名最高的化合物将通过二次筛选进行验证，评估再现性、剂量反应、广度和特异性。三级分析涉及病毒与多种HIV-1和其他逆转录病毒包膜糖蛋白的单轮复制，可以以中等吞吐量进行，并将提供效力，广度和特异性的信息。评价作用机制的其他三级分析在美国已经建立

DESCRIPTION (provided by applicant): Human immunodeficiency virus (HIV-1) is the etiologic agent of acquired immunodeficiency syndrome (AIDS). The global HIV-1 pandemic (~35 million people infected) is sustained by 2-3 million new infections annually. Changing the course of this pandemic requires prevention of HIV-1 transmission, most of which occurs sexually. In the absence of an effective vaccine, modalities that block sexual HIV-1 transmission are desperately needed. Recently, the use of specific antiretroviral drugs has been investigated and shown to partially protect at-risk sex partners from HIV-1 infection. However, partial efficacy, drug side effects and the emergence of drug-resistant viruses limit the general applicability of these particular agents as prophylactic measures. New broadly active antiviral agents that can be used as topical microbicides could remedy these deficiencies. The HIV-1 envelope glycoproteins (Envs), which mediate virus entry into target cells, represent attractive targets for such prophylactic agents. The HIV-1 Envs are exposed on the viral surface, are accessible to water-soluble inhibitors and are present in low numbers on each virion. Env inhibitors used as microbicides need not be systemically absorbed or taken up by host cells, limiting potential toxicity. Conserved elements of Env mediate receptor binding, conformational changes, and membrane fusion, providing several potential targets for inhibition. Although some HIV-1 entry inhibitors have been identified, drug-resistant HIV-1 variants either exist naturally o develop during treatment. We have devised a screening strategy to identify new broad-range inhibitors of HIV-1 entry. In our screening assay, HIV-1 Env function leads to the fusion of Env-expressing cells with cells expressing the viral receptors. This cell-cell fusion assay and a specificity control assay will be used in parallel in a primary screen of the NIH small-molecule library. The highest-ranked compounds will be validated by a secondary screen that assesses reproducibility, dose-response, breadth and specificity. Tertiary assays involving single-round replication of viruses with multiple HIV-1 and other retroviral envelope glycoproteins can be performed at modest throughput and will provide information on potency, breadth and specificity. Additional tertiary assays to evaluate mechanism of action are well-established in the principal investigator's laboratory, and will be applied to selected compounds. Specific and broad-range inhibitors will be modified to improve potency while retaining breadth. The compounds identified in this study could potentially be useful as prophylactic microbicides, as treatments for already infected individuals, and as probes to understand the complex, multi-step process of HIV-1 entry.