Inhibiting Immune Evasion by HIV-1 Nef to Facilitate Eradication

抑制 HIV-1 Nef 的免疫逃避以促进根除

基本信息

批准号：
8770025
负责人：
John C. Guatelli
金额：
$ 18.9万
依托单位：
VETERANS MEDICAL RESEARCH FDN/SAN DIEGO
依托单位国家：
美国
项目类别：
财政年份：
2013
资助国家：
美国
起止时间：
2013-12-01 至 2016-09-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8770025
关键词：
Amino Acids Bioinformatics Biological Assay Cause of Death Cell Death Cell membrane Cell model Cell surface Cells Clathrin Adaptors Complex Computing Methodologies Cytoplasmic Tail Cytotoxic T-Lymphocytes Data Drug Targeting Engineering Failure Gene Expression HIV HIV-1 Host Defense Human Immune Immunity In Vitro Infection Infection Control Knowledge Latent Virus Lead MHC Class I Genes Mediating Modeling Molecular Mus Mutate Patients Peptides Pharmacotherapy Phase Proteins Resistance Roentgen Rays Structure Surface T memory cell T-Cell Receptor T-Lymphocyte Testing Transcription Factor AP-1 Viral Viral Antigens Viral Genes Virus adaptive immunity base design drug discovery empowered high throughput screening in vitro Model in vivo in vivo Model inhibitor/antagonist killings nef Protein novel peptidomimetics prevent prototype public health relevance reactivation from latency scaffold small molecule treatment strategy viral resistance

项目摘要

DESCRIPTION (provided by applicant): Immune evasion by HIV-1 accessory proteins likely contributes to the failure of host immunity to control the infection and may complicate approaches to eradication. We will test the hypothesis that inhibiting viral evasion of host immunity can contribute to a curative treatment strategy. Recent data suggest that reactivation of viral gene expression is not sufficient to cause the death of cells latently infected with HIV-1 cell-death requires the killing-activity of cytotoxic T lymphocytes (CTL). Consequently, our strategy focuses on HIV-1 Nef, which provides viral evasion of CTL-activity. Nef prevents class I MHC from reaching the plasma membrane, decreasing the concentration of viral antigens at the cell surface and inhibiting the killing of infected cells by CTL. Interference with this activity o Nef should empower CTL and facilitate the eradication of infected cells from the host. In principle, this strategy applies to "reservoir" cells expressing low levels of viral antigens as well as to CD-positive memory T cells in which latent virus is reactivated pharmacologically. During the R21 phase of this proposal, we will validate the importance of Nef in viral resistance to eradication by showing that primary T cells in which virus is reactivated from latency display reduced surface levels of MHC-I and that this reduction is Nef-dependent and associated with resistance to CTL-mediated killing. Concurrently, we will use our recent knowledge of how Nef modulates MHC-I at the molecular and structural levels to identify small molecules capable of inhibiting this activity. We will exploit our X-ray crystallographic model of the complex formed by Nef, the cytoplasmic domain of the MHC-I α-chain, and the μ subunit of the endosomal clathrin adaptor AP1 to design prototypic peptide inhibitors and to devise a high throughput screen capable of identifying small molecule lead compounds. During the R33 phase, we will broaden our approach to drug discovery by including a novel computational method that matches semi-rigid scaffold molecules displaying amino acid R groups to the structure of the complex. We will evaluate leads from this approach as well as from our high throughput screen using cell- based secondary screens and optimize them structurally. Lastly, we will use these small molecules in in vitro, ex vivo, and in vivo settings o establish that inhibiting Nef-mediated immune evasion can facilitate viral eradication.

描述（由适用提供）：HIV-1辅助蛋白的免疫进化可能导致宿主免疫学控制感染，并可能使根除方法复杂化。我们将检验以下假设：抑制宿主免疫学的病毒进化可以有助于治疗治疗策略。最近的数据表明，病毒基因表达的重新激活不足以导致受HIV-1细胞死亡感染的细胞死亡，因此我们的策略侧重于HIV-1 NEF，这提供了CTL活性的病毒演化。 NEF可防止I类MHC到达质膜，从而降低细胞表面病毒抗原的浓度，并抑制CTL杀死感染细胞的杀伤。干扰这种活性O NEF应赋予CTL能力，并促进从宿主中消除感染细胞。原则上，该策略适用于表达低水平病毒抗原的“储层”细胞，以及在药理学上重新激活潜在病毒的CD阳性记忆T细胞。在该提案的R21阶段中，我们将通过表明从潜伏期重新激活病毒的原代T细胞显示MHC-I的表面水平降低，并且这种降低与NEF依赖性并与对CTL介导的杀伤的抗性相关，从而验证NEF在病毒抗性中的重要性。同时，我们将使用我们最近对NEF调节MHC-I在分子和结构水平上如何调节能够抑制这种活性的小分子的知识。我们将利用由由 NEF，MHC-Iα链的细胞质结构域以及内体网旋蛋白适配器AP1的μ亚基，以设计原型肽抑制剂，并设计能够鉴定小分子铅化合物的高吞吐量。在R33阶段，我们将通过包括一种与半刚性支架分子相匹配的新计算方法来扩展我们的药物发现方法，显示氨基酸R基团与复合物的结构。我们将使用基于细胞的辅助屏幕从这种方法以及高吞吐量屏幕中评估潜在客户，并在结构上优化它们。最后，我们将在体外使用这些小分子，体内和体内环境o确定抑制NEF介导的免疫避免可以促进病毒逃避。