Epitope focusing using structure-based immunogen design approaches

项目概要/摘要 自从新型严重急性呼吸道综合征病毒2型（SARS-CoV-2）冠状病毒出现以来， 需要更好的框架，以迅速开发疫苗，应对新出现的病毒威胁，包括其他 冠状病毒的潜在大流行的关注，是明确的。一种方法是开发免疫原设计 利用病毒表面糖蛋白和其宿主细胞之间通常保守的界面的平台 受体。对于SARS-CoV-2，引发的抗体将靶向其“刺突”糖蛋白之间的相互作用， 和人血管紧张素转换酶2（ACE-2）受体。其他冠状病毒如SARS-CoV-1和 普通引起感冒NL 63也使用ACE-2，因此干扰这种保守相互作用的抗体 也可能防止未来新的冠状病毒也使用这种受体。这项拟议工作的目标是 是使用结构导向的、合理设计的新型免疫原，将免疫反应集中于ACE-2， SARS-CoV-2的受体结合界面。这可能为免疫原设计提供一个可推广的框架 这些策略可以在未来迅速用于对抗新出现的病毒。我将使用以下两个 设计方法：1）我将使用与SARS-CoV-2结构同源的分子支架 受体结合结构域（RBD），并用来自SARS的ACE-2受体结合基序（RBM）“重新浮现”它们- 二型冠状病毒因此，抗原性不同的支架将均匀地呈递保守的SARS-CoV-2 RBM 并将免疫反应集中于保守的界面。2)我会用高糖基化 SARS-CoV-2 RBD上的免疫显性非保护性表位，以指导针对 SARS-CoV-2 RBM。对于这两种方法，我将分析引发的免疫反应，以确定 免疫聚焦于SARS-CoV-2 RBM，获得中和谱和结构表征， 选择引发的抗体。总的来说，这些数据将提供深入了解如何掩盖和表面重塑， 决定性地将免疫应答导向保守的病毒表位。虽然我用SARS-CoV-2作为模型 病毒，这可以为未来的病毒病原体提供一个疫苗设计框架， 部署.

Project Summary/Abstract Since the emergence of the novel severe acute respiratory syndrome virus 2 (SARS-CoV-2) coronavirus, the need for better frameworks to rapidly develop vaccines in response to emerging viral threats, including other coronaviruses of potential pandemic concern, is clear. One approach is to develop an immunogen design platform that leverages the often-conserved interface between viral surface glycoproteins and their host cellular receptor(s). For SARS-CoV-2, elicited antibodies would target the interaction between its “spike” glycoprotein and the human angiotensin-converting enzyme 2 (ACE-2) receptor. Other coronaviruses like SARS-CoV-1 and the common cold-causing NL63 also use ACE-2, thus antibodies that interfere with this conserved interaction might also protect against future novel coronaviruses that also use this receptor. The goal of this proposed work is to use structure-guided, rational design of novel immunogens to focus the immune response to the ACE-2 receptor binding interface of SARS-CoV-2. This may provide a generalizable framework of immunogen design strategies that can be rapidly used to combat novel emerging viruses in the future. I will use the following two design approaches: 1) I will use molecular scaffolds that are structurally homologous to the SARS-CoV-2 receptor binding domain (RBD) and “resurface” them with the ACE-2 receptor binding motif (RBM) from SARS- CoV-2. As a result, the antigenically distinct scaffolds will uniformly present the conserved SARS-CoV-2 RBM and will focus the immune response to the conserved interface. 2) I will use hyperglycosylation to mask immunodominant, non-protective epitopes on the SARS-CoV-2 RBD to direct the immune response to the SARS-CoV-2 RBM. For both approaches, I will analyze the elicited immune response to determine the extent of immune focusing to the SARS-CoV-2 RBM, obtain neutralization profiles and structurally characterize down- selected elicited antibodies. Collectively, these data will provide insight into how masking and resurfacing can determinatively direct the immune response to a conserved viral epitope. While I use SARS-CoV-2 as a model virus, this could provide a vaccine design framework for future viral pathogens with the potential for rapid deployment.