Investigating an interface between gp120 and gp41 for HIV entry inhibition

研究 gp120 和 gp41 之间的界面以抑制 HIV 进入

• 批准号: 8264744
• 负责人: MICHAEL B ZWICK
• 金额: $ 18.95万
• 依托单位: SCRIPPS RESEARCH INSTITUTE, THE
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-06-01 至 2014-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8264744
• 关键词: AIDS/HIV problem; Address; Affect; Affinity; Antiviral Agents; Binding; Binding Sites; Biological Assay; CCR5 gene; Cells; Chemicals; Complement; Complex; Data; Development; Discrimination; Disulfides; Drug Design; Drug resistance; Elements; Future; Genetic Polymorphism; HIV; HIV Entry Inhibitors; HIV Envelope Protein gp120; HIV Envelope Protein gp41; HIV Fusion Inhibitors; HIV-1; Health; Indium; Investigation; Kinetics; Label; Lead; Libraries; Link; Lipids; Mediating; Modeling; Molecular; Molecular Conformation; Molecular Weight; Mutation; Outcome; Peptides; Pharmaceutical Preparations; Pharmacotherapy; Phenotype; Resistance; Role; Site; Son of Sevenless Proteins; Specificity; Structure; Structure-Activity Relationship; Testing; Tracer; Ursidae Family; Variant; Virus; analog; arm; base; combat; design; dimer; drug development; env Glycoproteins; functional outcomes; high throughput screening; inhibitor/antagonist; mimetics; mutant; novel; pandemic disease; research study; resistance mutation; stoichiometry; tool; translational study

DESCRIPTION (provided by applicant): We recently described an HIV fusion inhibitor, PF-68742, that targets a novel site involving the fusion peptide (FP) and disulfide loop (DSL) region of gp41. We have since discovered mutations in the C5 region of gp120 that profoundly affect sensitivity of HIV to PF-68742. The results suggest that PF-68742 binds to native HIV Env in an interface between gp120 and gp41 involving FP, DSL and C5. Interestingly, antiviral activities of several other entry inhibitors to HIV show complex but poorly explained sensitivity to mutations involving the gp120-gp41 interface and/or FP. As examples, VIRIP is a recently described fusion inhibitor that targets FP but HIV resistance and escape to VIRIP has not been well studied, whereas mutations in FP have recently been shown to profoundly affect HIV sensitivity to CCR5-dependent entry inhibitors such as maraviroc (MVC). Interestingly, FP-mediated resistance or escape to these inhibitors has been associated with 'negative' inhibition, in which infectivity of particular variants of HIV is increased in the presence of low concentrations of inhibitor, followed by inhibition at higher concentrations. These commonalities in the functional outcome of different entry inhibitor activities involving mutations at the gp120-gp41 interface have implications for drug development and therefore warrant further investigation. To gain a better understanding of the fine specificity and mechanism of action of PF-68742, in Specific Aim 1, we will use mutagenic profiling to probe structural determinants of Env that affect HIV sensitivity to PF-68742 in comparison to VIRIP and MVC. The experiments will address the role of FP and its mutation in generating multi-class drug resistance, will help outline the functional relationship between FP and other regions of Env, and will inform downstream screens for new entry inhibitors. Potential for synergy of PF-68742 and VIRIP with other entry inhibitors will also be evaluated. In Specific Aim 2, we will prepare tracer labeled versions of PF-68742 and VIRIP to physically probe the exposure of specific elements of their binding sites in different activation states of native Env, as well as for use in probing relevant Env mimetic molecules that bear a gp120-gp41 interface. In Specific Aim 3, we will screen a diverse chemical compound library with the aim of identifying agents that inhibit HIV by binding to and perturbing the conserved subunit interfaces within Env that affect FP. Potential for 'hit' compounds to affect Env stability and complement or synergize with PF-68742, VIRIP or other existing fusion inhibitors will also be tested. Overall, the structure-function information on Env that will be gained, the tools and novel Env trimer- binding assays that we will develop, as well as the new entry inhibitor leads we will identify are relevant to the design and discovery of HIV entry inhibitors to a conserved gp120-gp41 interface in native HIV-1 Env. PUBLIC HEALTH RELEVANCE: New and better drugs are desired that can block HIV before it enters into host cells. To accelerate discovery and development of such drugs, we wish to understand the mechanisms of a recently described, first-in-class HIV entry inhibitor, and distinguish its unique features from those it shares with other key entry inhibitor drugs. We will produce valuable tools for probing its binding site, and then look for relevant new HIV drug leads.

描述（由申请人提供）：我们最近描述了HIV融合抑制剂PF-68742，该抑制剂针对涉及GP41的融合肽（FP）和二硫化物环（DSL）区域的新型位点。此后，我们在GP120的C5区域中发现了突变，这些突变深远影响HIV对PF-68742的敏感性。结果表明，PF-68742在涉及FP，DSL和C5的GP120和GP41之间的接口中与天然HIV ENV结合。有趣的是，其他几种艾滋病毒抑制剂的抗病毒活性表现出复杂但对涉及涉及GP120-GP41界面和/或FP的突变的敏感性。作为示例，VIRIP是一种最近描述的融合抑制剂，靶向FP，但抗HIV耐药性和逃生对VIRIP的研究尚未得到很好的研究，而FP中的突变最近显示出对CCR5依赖性进入抑制剂（如Maraviroc（MARAVIROC）（MVC）（MVC）的HIV敏感性。有趣的是，FP介导的抗药性或对这些抑制剂的逃脱性与“阴性”抑制有关，在低浓度的抑制剂存在下，特定艾滋病毒特定变异的感染性增加，然后在较高浓度下抑制。在GP120-GP41界面上涉及突变的不同进入抑制剂活性的功能结果中的这些共同点对药物开发有影响，因此值得进一步研究。为了更好地了解PF-68742的良好特异性和作用机理，在特定的目标1中，我们将使用诱变分析来探测ENV的结构决定因素，这些决定因素影响HIV对PF-68742的敏感性与VIRIP和MVC相比。该实验将解决FP的作用及其在产生多类耐药性中的突变，有助于概述FP与ENV的其他区域之间的功能关系，并将为下游屏幕提供新的进入抑制剂的信息。还将评估PF-68742和VIRIP与其他入口抑制剂的协同作用。在特定的目标2中，我们将准备示踪剂标记的PF-68742和VIRIP，以物理探测其结合位点在不同活化态的特定元素的暴露，以探测具有GP120-GP41接口的相关ENV模拟分子。在特定的目标3中，我们将筛选一个多样化的化学复合文库，目的是通过与影响FP的ENV结合并扰动保守的亚基界面来识别抑制HIV的药物。还将测试“命中”化合物的潜力，以影响ENV稳定性并与PF-68742，VIRIP或其他现有融合抑制剂进行补充或协同作用。总体而言，我们将开发的工具和新颖的结合测定法以及我们将确定的新进入抑制剂引线的结构功能信息，工具和新型ENV固定测定方法以及新的入口抑制剂引线与天然HIV HIV-1 Envy中保守的GP120-GP41界面的设计和发现有关。 公共卫生相关性：需要新的和更好的药物，可以在艾滋病毒进入宿主细胞之前阻止艾滋病毒。为了加速此类药物的发现和开发，我们希望了解最近描述的第一类HIV进入抑制剂的机制，并将其独特特征与具有其他关键入口抑制剂药物共享的特征区分开来。我们将生产有价值的工具来探测其结合部位，然后寻找相关的新艾滋病毒药物铅。