Structure-guided immunogens to elicit pan-coronavirus B cell responses

结构引导免疫原引发泛冠状病毒 B 细胞反应

基本信息

批准号：
10420514
负责人：
Aaron Gregory Schmidt
金额：
$ 193.41万
依托单位：
WASHINGTON UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2022
资助国家：
美国
起止时间：
2022-09-02 至 2025-08-31
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10420514
关键词：
2019-nCoV ACE2 Antibodies Antigens Avidity B-Cell Antigen Receptor B-Lymphocytes Binding Biochemical Biological Assay Biophysics Cells Chad Complex Coronavirus Cryoelectron Microscopy Development Engineering Epitopes Evaluation Frequencies Future Genes Glycoproteins Humoral Immunities Immune Immune response Immunity Laboratories Link Masks Merbecovirus Middle East Respiratory Syndrome Coronavirus Molecular Molecular Conformation Monoclonal Antibodies Output Polysaccharides Protein Binding Domain Proteins Recombinants Recording of previous events Role SARS coronavirus Sarbecovirus Serology Site Structure Surface System Vaccinated Vaccinee Vaccines Variant Vesicular stomatitis Indiana virus Viral Viral Vaccines Virus X-Ray Crystallography base betacoronavirus coronavirus receptor cross reactivity crosslink design glycosylation human subject immunogenicity interest lumazine nanoparticle next generation non-Native novel coronavirus pandemic disease rational design receptor receptor binding reconstruction response scaffold universal coronavirus vaccine vaccine development vaccine formulation vaccine platform vector

项目摘要

Project Summary The global pandemic caused by Severe Acute Respiratory Syndrome virus 2 (SARS-CoV-2) coronavirus (CoV) has highlighted the need to develop next-generation viral vaccines that offer protection against future Sarbecoviruses and Merbecoviruses of concern. One approach is to implement structure-based immunogen design strategies that elicit humoral responses to conserved sites on the surface-exposed spike (S) viral glycoprotein. Potential sites include the receptor binding domain (RBD) and the receptor binding motif (RBM) required for viral entry. Other conserved sites on S, outside the RBD, may also be targets of both neutralizing and non-neutralizing responses offering broad CoV protection. Project 1 will combine computational, structural, biophysical, and single B cell analyses to design S and RBD immunogens that elicit broad-spectrum humoral immunity against CoVs. Based on evolutionary analysis of CoV sequences, it is unlikely that a single antigen will confer broad enough immunity against the entire Betacoronavirus genus; we therefore anticipate generating a polyvalent S or RBD containing vaccine (with Project 3). Initially, we prioritize ACE2-receptor using CoVs as a proof-of-concept but envision that our design principles can be extended to other emerging CoVs where ACE2 is not the receptor. The Schmidt laboratory will implement structure-guided immunogen design strategies to focus immune responses towards conserved epitopes on the RBM and RBD. We will use heterologous CoV RBDs as molecular scaffolds to present selected ACE2-binding CoV RBMs and further immune focus using engineered glycans to mask non-conserved epitopes. The Scheuermann laboratory will use ancestral reconstructions to identify extant CoVs as additional S-based immunogens. The Ellebedy laboratory will isolate monoclonal antibodies (mAbs) from naturally infected, vaccinated, or naïve human subjects to define CoV cross- reactive, conserved epitopes on S recognized by neutralizing and non-neutralizing mAbs. We will define the breadth of mAb cross-reactivity, cross-neutralization, and effector functions (with Project 3). The Fremont laboratory will perform structural analyses by X-ray crystallography and cryo-electron microscopy (Fremont laboratory) of the isolated mAbs to define targeted epitopes on S; this information will aid in iterative immunogen optimization to elicit responses to these newly defined, cross-reactive epitopes. The output of Project 1 will be optimized RBD and S genes to transfer to Project 3 for vaccine formulation in VSV or ChAd vaccine platforms.

项目概要由严重急性呼吸系统综合症病毒 2 (SARS-CoV-2) 冠状病毒 (CoV) 引起的全球大流行强调需要开发下一代病毒疫苗来预防未来值得关注的 Sarbecoviruses 和 Merbecoviruses 的一种方法是实施基于结构的免疫原。设计策略，引发对表面暴露的刺突（S）病毒保守位点的体液反应糖蛋白的潜在位点包括受体结合域（RBD）和受体结合基序（RBM）。 RBD 之外的 S 上的其他保守位点也可能是两者中和的目标。项目 1 将结合计算、结构、生物物理和单 B 细胞分析，设计可引发广谱体液免疫的 S 和 RBD 免疫原根据对冠状病毒序列的进化分析，单一抗原不太可能产生针对冠状病毒的免疫力。赋予针对整个β冠状病毒属的足够广泛的免疫力；因此，我们预计会产生一种含有多价 S 或 RBD 的疫苗（项目 3）最初，我们优先考虑使用 CoV 作为 ACE2 受体。概念验证，但设想我们的设计原则可以扩展到其他新兴的冠状病毒，其中 ACE2 不是受体。施密特实验室将实施结构引导的免疫原设计策略我们将使用异源 CoV 将免疫反应集中在 RBM 和 RBD 上的保守表位。 RBD 作为分子支架来呈现选定的 ACE2 结合 CoV RBM 并使用进一步的免疫焦点 Scheuermann 实验室将使用祖先的工程聚糖来掩盖非保守表位。 Ellebedy 实验室将进行重建，以将现有的 CoV 识别为额外的基于 S 的免疫原。来自自然感染、肺炎或幼稚人类受试者的单克隆抗体 (mAb)，用于定义 CoV 交叉抗体我们将定义中和性和非中和性单克隆抗体识别的 S 上的反应性保守表位。 mAb 交叉反应性、交叉中和和效应器功能的广度（与项目 3 一起）。实验室将通过 X 射线晶体学和冷冻电子显微镜（弗里蒙特）进行结构分析实验室）分离的单克隆抗体以确定 S 上的目标表位；该信息将有助于迭代免疫原优化以引发对这些新定义的交叉反应表位的反应项目 1 的输出将是。优化 RBD 和 S 基因，转移至项目 3，用于 VSV 或 ChAd 疫苗平台中的疫苗配制。