Potent broadly neutralizing antibody development against the HIV-1 fusion peptide epitope

项目总结/摘要 针对人类免疫缺陷病毒-1（HIV-1）的疫苗和抗体干预措施已使 取得了巨大的进展，但尚未准备好广泛的临床应用。预防新感染的疫苗可以 通过阻断传播，为结束HIV-1大流行提供了重大推动力。HIV-1融合肽（FP） 已经显示出作为广泛中和抗体（bNAb）导向的疫苗靶位点的前景， 抗原可以有效地引发和扩增靶向FP的B细胞应答。然而，HIV-1基因多样性在 FP和已知抗体在FP位点的有限的效力和中和宽度已经减缓了FP的进展。 FP指导的干预措施。更好地了解抗FP抗体如何实现精确中和 针对HIV-1的效力和广度将使改进的疫苗和治疗开发成为可能。该项目将 探索抗FP抗体的关键突变途径，为 更好的抗HIV-1 FP抗体和疫苗解决方案。 该项目的目标1将应用精确的突变扫描和定向进化来设计精致的 靶向HIV-1 FP的抗体的中和效力。我们将实施一种新的基于单细胞液滴的 我们实验室建立的筛选平台，可根据中和作用直接鉴定抗体变体 功能目标1将增强抗FP抗体的广度和效力，超越目前同类最佳的例子，并通过 研究这些抗体，我们将了解更多关于有效保护的结构和分子要求。 在FP。对于目标2，我们将探索可以增加交叉反应性和广度的亲和力突变景观 对照FP，并将这些数据与目标1中的中和概况进行比较，以了解 亲和力增强和中和增强突变。最后，在目标3中，我们将探讨抗体如何可变 区域突变也可以影响Fc效应器功能，以及HIV-1 Fc效应器蛋白参与如何共同影响Fc效应器功能。 与给定突变对不同HIV-1病毒分离株的亲和力和中和作用相关。数据来自Aim 3将加速我们对bNAb Fc效应子募集机制的理解，并与平行的 Fab介导的中和效力的改善。 该项目阐明了中和效力、抗原亲和力和效应子之间的重要关系 在靶向FP位点的抗体中起作用。我们的多平台方法可实现最全面的 迄今为止，抗FP抗体的功能研究，具有遗传、生物物理和 功能特性，导致精致的抗HIV-1活性。产生新的bNAb并获得知识 该项目将为开发全球相关疫苗提供关键信息和资源， 抗HIV-1 FP的治疗剂。

Project Summary/Abstract Vaccines and antibody interventions against human immunodeficiency virus-1 (HIV-1) have made tremendous progress, but are not yet ready for broad clinical use. A vaccine that prevents new infections could provide a major boost to ending the HIV-1 pandemic by blocking transmissions. The HIV-1 fusion peptide (FP) has shown promise as a broadly neutralizing antibody (bNAb)-directed vaccine target site because vaccine antigens can effectively prime and expand B cell responses targeting FP. However, HIV-1 genetic diversity at FP and the limited potency & neutralization breadth of known antibodies at the FP site has slowed progress for FP-directed interventions. A better understanding of how anti-FP antibodies can attain exquisite neutralization potency and breadth against HIV-1 will enable improved vaccines and therapeutic development. This project will explore critical mutational pathways for anti-FP antibodies, providing new molecular and functional insights for better antibody & vaccine solutions against HIV-1 FP. Aim 1 of the project will apply precision mutational scanning and directed evolution to engineer exquisite neutralization potency for antibodies targeting HIV-1 FP. We will implement a new single-cell droplet-based screening platform established by our laboratory to directly identify antibody variants based on neutralization function. Aim 1 will enhance anti-FP antibody breadth & potency beyond current best-in-class examples, and by studying these antibodies we will learn more about the structural & molecular requirements for potent protection at FP. For Aim 2, we will explore the affinity mutational landscapes that can increase cross-reactivity and breadth against FP, and compare those data with neutralization profiles in Aim 1 to understand the connections between affinity-enhancing and neutralization-enhancing mutations. Finally, in Aim 3 we will explore how antibody variable region mutations can also influence Fc-effector function, and how HIV-1 Fc effector protein engagement co- correlates with affinity and neutralization of a given mutation against diverse HIV-1 viral isolates. Data from Aim 3 will accelerate our understanding of bNAb Fc effector recruitment mechanisms, and synergize with parallel improvements in Fab-mediated neutralization potency. This project elucidates the critical relationships between neutralization potency, antigen affinity, and effector function in antibodies targeting the FP site. Our multi-platform approach enables the most comprehensive functional study of anti-FP antibodies to date, with layered characterization of the genetic, biophysical, and functional features that lead to exquisite anti-HIV-1 activity. The new bNAbs generated and knowledge gained by this project will provide critical information and resources to develop globally relevant vaccines and therapeutics against HIV-1 FP.