Novel HCV vaccine antigens and nanoparticles

新型 HCV 疫苗抗原和纳米颗粒

• 批准号: 10557879
• 负责人: Jiang Zhu
• 金额: $ 56.97万
• 依托单位: SCRIPPS RESEARCH INSTITUTE, THE
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-02-01 至 2027-01-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10557879
• 关键词: Animal Model; Antibodies; Antibody Response; Antibody-mediated protection; Antigen Presentation; Antigens; Antiviral Agents; Artificial nanoparticles; B cell repertoire; B-Lymphocytes; Binding; Biological Assay; Cell Separation; Cirrhosis; Clinical Trials; Complex; Computer Models; Data; Developing Countries; Development; Engineering; Epitopes; Face; Genetic; Genotype; Glycoproteins; Goals; Hepatitis C Vaccine; Hepatitis C virus; Heterodimerization; Human; Immune system; Immunization; Immunize; Immunodominant Epitopes; In Vitro; Infection; Knowledge; Macaca mulatta; Modeling; Modification; Molecular Conformation; Mus; Mutagenesis; Outcome; Polysaccharides; Population; Predisposition; Primary carcinoma of the liver cells; Production; Property; Proteins; Public Health; Reaction; Recombinants; Scaffolding Protein; Scanning; Site; Structure; Surface; Transmembrane Domain; Vaccination; Vaccine Antigen; Vaccine Design; Vaccines; Viral; Viral Antigens; Viral Envelope Proteins; Virus; clinical development; combat; cost effective; design; flexibility; immunogenicity; improved; in vivo; in vivo evaluation; marginalization; mouse model; nanoparticle; neutralizing antibody; next generation sequencing; nonhuman primate; novel; pandemic virus; preference; protein folding; rational design; response; self assembly; social group; vaccine candidate; vaccine development; vaccine immunogenicity; vaccine-induced antibodies; virus envelope

Project Summary Hepatitis C virus (HCV) infects 1-2% of the world population and poses a significant threat to public health. Recent studies have identified a panel of broadly neutralizing antibodies (bnAbs) and their genetic preferences. The crystal structures of various HCV E2 constructs in complex with bnAbs and non-nAbs provide a structural basis for rational vaccine design. In Project 2 of this P01 proposal, we will combine structural optimization of HCV antigens, nanoparticle engineering, in vivo assessment, and next-generation sequencing (NGS) of B-cell repertoires to assist in rational design of HCV vaccines that can elicit a bnAb response. The Specific Aims in this project are: (1) To develop vaccine antigens to target multidonor class antibody responses. The major virus neutralizing site, the E2 neutralizing face (E2 NF), is a well-known multidonor class antibody target on HCV. E2 NF is conformationally flexible and is surrounded and protected by immunodominant variable loops and N-glycans. The antigenic surface at and around E2 NF will be optimized by computational modeling and mutagenesis scanning to “lock” E2 NF into desired neutralizing conformations. A rigid E2 NF, together with modifications to improve protein folding and to minimize the decoy effect of immunodominant epitopes, should improve the immunogenicity of vaccine antigens and as a result elicit multidonor class bnAbs to the conserved neutralizing epitopes. (2) To develop E1E2-based vaccine antigens. In addition to E2 NF, the native E1E2 complex also present other conserved bnAb epitopes. We will apply scanning mutagenesis to the interface of E1 and E2 ectodomains and design novel E1 and E2 fusion constructs to improve the stability and production of the soluble E1E2 complex for the elicitation of bnAbs targeting the quaternary structure of the complex. (3) To develop self-assembling antigen-presenting nanoparticle vaccines. The engineered E2 and E1E2 complex will be fused with the scaffold proteins of different nanoparticle platforms to identify a platform optimal for the multimeric display of HCV antigens to the immune system. Based on our preliminary data, this strategy will greatly improve the immunogenicity of vaccine antigens and elicit a rapid and potent nAb response. (4) To evaluate immunogenicity and antibody responses of vaccine candidates in the mouse and non-human primate (NHP) rhesus macaque models. The engineered E2, E1E2 antigens and nanoparticles will first be studied in mice to confirm their immunogenicity in vivo and their ability to elicit antibodies that can bind and neutralize HCV. The antigens and nanoparticles with the best properties in vitro and in mice will be studied further using the NHP model. We have recently shown that rhesus macaques react to E1E2 immunization in a manner highly reminiscent to that used by humans and develop bnAbs against E2 NF with genetic similarity to human bnAbs. Here, we will immunize NHPs, identify bnAbs, and perform repertoire NGS to evaluate selected antigen designs. The outcome of Project 2 would be a set of well-characterized HCV vaccine candidates.

项目概要 丙型肝炎病毒 (HCV) 感染世界人口的 1-2%，对公众健康构成重大威胁。 最近的研究已经确定了一组广泛中和抗体（bnAb）及其遗传偏好。 与 bnAb 和非 nAb 复合的各种 HCV E2 构建体的晶体结构提供了结构 为合理的疫苗设计奠定基础。在本次P01提案的项目2中，我们将结合结构优化 HCV 抗原、纳米颗粒工程、体内评估和 B 细胞下一代测序 (NGS) 有助于合理设计能够引发 bnAb 反应的 HCV 疫苗。具体目标 该项目是： (1) 开发针对多供体类抗体反应的疫苗抗原。这 主要病毒中和位点，E2 中和面 (E2 NF)，是众所周知的多供体类抗体靶点 关于丙肝病毒。 E2 NF 构象灵活，被免疫显性变量包围和保护 环和 N-聚糖。 E2 NF 处及其周围的抗原表面将通过计算模型进行优化 诱变扫描将 E2 NF“锁定”为所需的中和构象。严格的 E2 NF，以及 修饰以改善蛋白质折叠并尽量减少免疫显性表位的诱饵效应，应该 提高疫苗抗原的免疫原性，从而引发保守的多供体类 bnAb 中和表位。 (2)开发基于E1E2的疫苗抗原。除E2 NF外，原生E1E2 复合物还存在其他保守的 bnAb 表位。我们将扫描诱变应用于 E1 和 E2 胞外域并设计新型 E1 和 E2 融合构建体以提高稳定性和产量 检测可溶性 E1E2 复合物，以引发针对该复合物四级结构的 bnAb。 (3) 开发自组装抗原呈递纳米颗粒疫苗。工程设计的 E2 和 E1E2 复合物将与不同纳米颗粒平台的支架蛋白融合，以确定最佳平台 用于向免疫系统展示 HCV 抗原的多聚体。根据我们的初步数据，该策略 将大大提高疫苗抗原的免疫原性并引发快速有效的nAb反应。 (4) 至 评估候选疫苗在小鼠和非人类体内的免疫原性和抗体反应 灵长类动物（NHP）恒河猴模型。工程化的 E2、E1E2 抗原和纳米颗粒将首先被 在小鼠中进行研究，以确认它们的体内免疫原性以及它们引发可以结合和的抗体的能力 中和丙型肝炎病毒。将研究体外和小鼠体内具有最佳特性的抗原和纳米颗粒 进一步使用NHP模型。我们最近发现恒河猴对 E1E2 免疫产生反应 方式与人类使用的方式高度相似，并开发了针对 E2 NF 的 bnAb，其遗传相似性 人类 bnAb。在这里，我们将对 NHP 进行免疫，鉴定 bnAb，并执行全 NGS 来评估所选的 抗原设计。项目 2 的成果将是一组特征良好的 HCV 候选疫苗。