New Inhibitors of HIV Replication

描述(申请人提供)：艾滋病毒进入潜伏状态的能力对通过抗逆转录病毒疗法根除艾滋病毒-1感染造成了根本障碍，并重新引起了人们对开发阻止潜伏前病毒重新出现的抑制剂的兴趣。本研究项目的目标是发现新的抗病毒药物，这些药物针对人类免疫缺陷病毒(HIV)Tat蛋白和TAR RNA之间的基本相互作用，TAR RNA是积极调节HIV-1启动子转录延伸所必需的。TAT-TAR相互作用的抑制剂将能够阻止病毒在急性和慢性感染细胞中的复制，并选择性地靶向在高效抗逆转录病毒疗法(HAART)存在下持续缓慢复制的病毒储存库。在之前的资助期间，我们使用了一种基于结构设计的模拟多肽的方法来发现TAT-TAR相互作用的有效抑制剂。通过TAT依赖的机制，模拟肽化合物可穿透细胞膜，抑制TAT依赖的人细胞反式激活，并抑制病毒在原代淋巴细胞中的复制。我们现在建议：1.优化TAT蛋白环肽模拟物的活性，以抑制HIV-1 TAT-TAR相互作用和细胞提取物中的TAT活性。2.扩展多肽，以额外靶向Cyclin T1与TAR RNA顶端环的相互作用，从而通过两种机制同时阻止TAT-TAR-CycT1三元复合体的形成和PTEF-b激酶的募集3.优化模拟肽的摄取和细胞定位，并在基于功能细胞的检测中评价先导化合物的活性4.评价先导化合物抑制病毒复制的活性，并研究在模拟肽抑制剂存在的情况下病毒出现抗药性。该项目将提供指导这些化合物的药理开发所需的信息。我们非常有信心，在这项计划的过程中，可以开发出ICSOS远低于100纳米的高选择性化合物。

DESCRIPTION (provided by applicant): The ability of HIV to enter a latent state creates a fundamental obstacle to the eradication of HIV-1 infection by anti-retroviral therapy and has prompted renewed interest in developing inhibitors that block the re-emergence of latent proviruses. The goal of this research project is to discover new antiviral drugs that target the essential interaction between the Human Immunodeficiency Virus (HIV) Tat protein and TAR RNA, which is required to positively regulate transcriptional elongation from the HIV-1 promoter. An inhibitor of the Tat-TAR interaction would be able to block viral replication both in acutely and in chronically infected cells and selectively target the reservoir of slowly replicating viruses that persists in the presence of Highly Active Anti Retroviral Therapy (HAART). In the previous funding period, we utilized a peptidomimetic approach grounded in structure-based design to discover potent inhibitors of the Tat-TAR interaction. The lead peptidomimetic compounds penetrate cellular membranes, inhibit Tat-dependent transactivation in human cells and inhibit viral replication in primary lymphocytes for a variety of strains through a Tat-dependent mechanism. We now propose to: 1. Optimize the activity of the cyclic peptide mimetics of the Tat protein to inhibit the HIV-1 Tat-TAR interaction and Tat activity in cell extracts 2. Extend the peptide to additionally target the interaction of cyclin T1 with the apical loop of TAR RNA, thereby preventing formation of the Tat-TAR-cycT1 ternary complex and recruitment of the Ptef-b kinase by two mechanisms simultaneously 3. Optimize the uptake and cellular localization of the peptidomimetics and evaluate the activity of the lead compounds in functional cell-based assays 4. Evaluate the activity of the lead compounds in inhibiting viral replication and study the emergence of resistance in the virus in the presence of the peptidomimetic inhibitors. The project will provide the information required to guide the pharmacological development of these compounds. We are very confident that highly selective compounds with ICSOs well below 100 nM can be developed in the course of this program.