Dissecting the Conformational Flexibility of HIV-1 Envelope Glycoproteins

剖析 HIV-1 包膜糖蛋白的构象灵活性

• 批准号: 10646287
• 负责人: Alon Herschhorn
• 金额: $ 57.08万
• 依托单位: UNIVERSITY OF MINNESOTA
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-06-15 至 2027-05-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10646287
• 关键词: Adopted; Affect; Amino Acids; Antibodies; Antibody Therapy; Antigens; Archives; Binding; Binding Sites; Biology; Cells; Complex; Cryoelectron Microscopy; Development; Electrons; Elements; Epitopes; Evolution; Generations; Glycoproteins; Goals; HIV; HIV Envelope Protein gp120; HIV Infections; HIV envelope protein; HIV-1; HIV-1 vaccine; Heterogeneity; Inpatients; Kinetics; Knowledge; Maps; Measures; Mediating; Modeling; Molecular; Molecular Conformation; Mutation; Pathway interactions; Patients; Persons; Preventive vaccine; Probability; Publishing; Resolution; Shapes; Source; Spectrum Analysis; Structure; Testing; Therapeutic Intervention; Time; Translating; V3 Loop; Vaccine Design; Vaccines; Variant; Viral; Virus; Work; design; flexibility; improved; in vivo; insight; latent HIV reservoir; neutralizing antibody; pandemic disease; preventive intervention; resistant strain; single-molecule FRET; targeted treatment; therapeutic development; transmission process; working group

ABSTRACT HIV-1 envelope glycoproteins (Envs) mediate viral entry into host cells and are the sole target of neutralizing antibodies. HIV-1 Envs of most primary HIV-1 strains typically exist in a closed conformation (State 1) and occasionally transit to downstream, more open conformations (State 2 and State 3). Thus, current knowledge guides immunogen design towards mimicking the Env closed conformation as the preferred target for eliciting broadly neutralizing antibodies (bnAbs) to block HIV-1 entry. However, Env preferred conformations of more than 37 million different circulating HIV-1 strains are unlikely to adopt exactly the same closed conformation. And we still do not know how different State 1 conformations of diverse natural HIV-1 variants are. Our hypothesis: State 1 Envs form a heterogenous group of Envs that exist in similar but not identical conformations. Accordingly, improved ability of bnAbs to recognize multiple Env conformations will broaden their neutralization activity. To test our hypothesis, we will assess the conformational heterogeneity of Envs from different strains and build mechanistic models for 1) Envs transitions, 2) generation and transmission of Envs that exist in specific conformations, and 3) broad recognition of different Env states. In Specific Aim 1 we will study the conformational diversity of transmitted/founder (T/F) HIV-1 strains, which can establish HIV-1 in vivo and are the only target of a preventive vaccine. We will study the mechanisms by which T/F Envs expose internal elements and how they transit to downstream conformations. In Specific Aim 2 we will investigate the generation and evolution of incompletely closed Env conformation. We will reconstruct the evolution pathway of T/Fs in patients by using available viral sequences to build evolved viruses at different time point followed by investigating changes in their conformational states over time. In parallel, we will study Env conformational diversity among HIV-1 strains that are archived in the latent HIV-1 reservoir of people living with HIV-1 and identify potential targets for therapeutic interventions. These approaches will allow us to build a mechanistic model for how incompletely closed Envs are generated, evolved, and transmitted. In Specific Aim 3 we will define important parameters for broad recognition of CD4-binding site (CD4-bs) on different Env conformations of diverse primary strains. We will study how the exceptionally broad N6 (CD4-bs) bnAb recognizes different Env conformations, will identify critical interactions with residues on open and closed Env conformations, and will solve cryo-EM structures of HIV-1 Envs in complex with N6 to define the mechanism of broad recognition. Overall, our study will provide high-resolution and comprehensive view on the biology of HIV-1 entry pathway, will refine the knowledge on HIV-1 Env conformations, and will form a strong basis for the development of new strategies for HIV-1 cure and vaccine design.

抽象的 HIV-1 包膜糖蛋白 (Envs) 介导病毒进入宿主细胞，是中和病毒的唯一目标 抗体。大多数主要 HIV-1 毒株的 HIV-1 包膜通常以闭合构象（状态 1）存在，并且 偶尔会过渡到下游、更开放的构象（状态 2 和状态 3）。因此，目前的知识 指导免疫原设计模仿 Env 闭合构象作为引发的首选目标 广泛中和抗体 (bnAb) 可阻止 HIV-1 进入。然而，Env 更喜欢的构象 超过 3700 万种不同的流行 HIV-1 毒株不太可能采用完全相同的闭合构象。和 我们仍然不知道不同天然 HIV-1 变异体的 1 态构象有何不同。 我们的假设：状态 1 Env 形成一组异质的 Env，它们存在于相似但不相同的环境中 构象。因此，bnAb 识别多种 Env 构象的能力的提高将 扩大其中和活动。 为了检验我们的假设，我们将评估不同菌株的 Envs 的构象异质性并构建 1）环境转换的机械模型，2）存在于特定环境中的环境的生成和传输 构象，以及3）对不同Env状态的广泛认可。在具体目标 1 中，我们将研究构象 传播/创建 (T/F) HIV-1 毒株的多样性，可以在体内建立 HIV-1，并且是感染的唯一目标 预防性疫苗。我们将研究 T/F Env 暴露内部元素的机制以及它们如何 过渡到下游构象。在具体目标 2 中，我们将研究 不完全封闭的 Env 构象。我们将利用以下方法重建患者 T/F 的进化路径 可用病毒序列在不同时间点构建进化病毒，然后调查 随着时间的推移它们的构象状态。与此同时，我们将研究 HIV-1 毒株之间的 Env 构象多样性 存档于 HIV-1 感染者的潜在 HIV-1 库中，并确定潜在的目标 治疗干预。这些方法将使我们能够建立一个机制模型来了解如何不完全地 封闭环境是生成、演化和传播的。在具体目标 3 中，我们将定义重要参数 广泛识别不同初级菌株的不同 Env 构象上的 CD4 结合位点 (CD4-bs)。我们 将研究极其广泛的 N6 (CD4-bs) bnAb 如何识别不同的 Env 构象，将识别 与开放和封闭 Env 构象上的残基的关键相互作用，并将解决 HIV-1 Envs 与 N6 复合，定义了广泛识别的机制。 总的来说，我们的研究将为 HIV-1 进入途径的生物学提供高分辨率和全面的观点， 将完善有关 HIV-1 Env 构象的知识，并将为开发新的药物奠定坚实的基础 HIV-1 治疗和疫苗设计策略。