Refinement of DNA-Launched NanoParticles decorated with Apex and CD4bs B cell lineage targeting Envs (DLNP-ACEs)

项目2--项目摘要 为了防止感染HIV-1，基于抗体的疫苗必须能够持续地诱导 广谱中和抗体(BNAbs)。事实证明，bNab在人类和非人类中都很难激发 灵长类(NHP)，部分原因是bNAb成熟所需的复杂发育途径， 来自HIV-1包膜糖蛋白(Env)和罕见前体B细胞的非靶向反应的竞争 频率在这个项目中，我们将开发候选免疫原，通过以下方式解决这些问题 各种各样的方法。首先，我们将使用基于结构和哺乳动物的展示技术来进一步 增强我们的领先候选人Q23.17 MD39的种系靶向能力。使用这些方法，我们 将开发能够靶向V2-顶端和CD4结合位点bNab表位的原生三聚体。这些 此外，还将设计三聚体免疫原，通过最大限度地减少竞争来限制偏离目标的反应 来自高度免疫优势的非中和抗体谱系。此外，我们将使用这些构造 开发新的针对SHIV的种系，并通过SHV感染识别增强免疫原 可以引导广度的发展。此外，通过对环境保护过程的结构分析，提出了一种新的环境保护模式。 AB共同进化，我们的目标是识别受感染的灵长类动物中bNab发育的决定因素，这将进一步 告知我们的免疫原设计流程。最后，我们将把这些与基因佐剂结合起来。 项目1和平台在项目3以及我们的新型DNA发射纳米颗粒(DLNP)方面取得了进展 站台。我们已经证明DLNPs在不需要复杂的cGMP的情况下提高了免疫原性 阻碍传统纳米疫苗临床开发步伐的过程。到时候我们会的 使用各种具有人类B细胞血统的创新小鼠模型，向下选择免疫原， 概括了人类B细胞竞争，并具有可调的bNab前体频率。这些老鼠会 为我们的主要候选者提供一个基准，使其进入GMP生产。我们将在一个 针对异源挑战的NHP模型，并通过这些组合方法，我们的目标是展示， 第一次，在NHP中保护免受异源第二层的挑战。

Project 2 - Project Summary In order to protect against HIV-1 acquisition, antibody-based vaccines must be able to consistently elicit broadly neutralizing antibodies (bnAbs). bnAb elicitation has proven difficult in humans and non-human primates (NHPs), in part because of the complex developmental pathways bnAbs require to mature, competition from off-target responses to the HIV-1 envelope glycoprotein (Env), and rare precursor B cell frequency. In this project we will develop candidate immunogens to address each of these problems through a variety of approaches. First, we will use structure-based and mammalian display techniques to further enhance the germline targeting ability of our lead candidate, Q23.17 MD39. Using these approaches, we will develop native-like trimers capable of targeting the V2-apex and CD4 binding site bnAb epitopes. These trimer immunogens will additionally be engineered to limit off-target responses by minimizing competition from highly immunodominant non-neutralizing antibody lineages. Furthermore, we will use these constructs to develop novel “germline targeting SHIVs”, and through SHIV-infection will identify boosting immunogens that can guide the development of breadth. Additionally, through structural analysis of the process of Env- Ab coevolution, we aim to identify determinants of bnAb development in infected primates, that will further inform our immunogen design process. Finally, we will complex these with genetic adjuvants developed in project 1 and platform advances in project 3, as well as with our novel DNA-Launched NanoParticle (DLNP) platform. We have shown DLNPs improve the immunogenicity while not requiring the complex cGMP processes that hamper the pace of clinical development for traditional nanoparticle vaccines. We will then down-select immunogens using a variety of innovative mouse models that harbor human B cell lineages, recapitulate human B cell competition and have tunable bnAb precursor frequencies. These mice will provide a benchmark for our lead candidates to be advanced into GMP production. We will test them in a NHP model for heterologous challenge, and through these combined approaches, we aim to demonstrate, for the first time, protection from heterologous tier-2 challenge in NHPs.