Structure, antigenicity, and function of HCMV fusogen gB

HCMV融合剂gB的结构、抗原性和功能

• 批准号: 10424572
• 负责人: Ekaterina Heldwein
• 金额: $ 75.86万
• 依托单位: TUFTS UNIVERSITY BOSTON
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-06-08 至 2026-05-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10424572
• 关键词: Antibodies; Antibody Response; Antigens; B-Lymphocytes; Binding; Biochemical; CMV glycoprotein B; Cell membrane; Cells; Closure by clamp; Complex; Cryoelectron Microscopy; Cytomegalovirus; Cytomegalovirus Infections; Cytomegalovirus Vaccines; Cytoplasmic Tail; Data; Development; Disease; Engineering; Epitopes; Fetus; Frequencies; Glycoproteins; Goals; Herpesviridae; Host Defense; Human; Human Herpesvirus 4; Immune response; Immunocompromised Host; Infection; Knowledge; Lead; Life; Mediating; Membrane; Membrane Fusion; Memory B-Lymphocyte; Molecular Conformation; Molecular Machines; Mothers; Nature; Passive Immunization; Penetration; Population; Preparation; Prevent viral transmission; Property; Proteins; Reagent; Regulatory Element; Research; Resolution; Role; Side; Simplexvirus; Site; Sorting - Cell Movement; Structure; Testing; Time; Translational Research; Transplant Recipients; Vaccines; Viral; Work; design; human pathogen; immunogenic; innovation; knowledge of results; neonate; neutralizing antibody; novel; prophylactic; receptor; research and development; response; seropositive; stem; tool; vaccination strategy; vaccine candidate; vaccine development

PROJECT SUMMARY/ABSTRACT Human cytomegalovirus (HCMV) is a highly successful human pathogens that infects much of the world’s population for life. While often asymptomatic, HCMV infections can cause severe disseminated disease in immunocompromised patients, e.g., transplant recipients, and developmental abnormalities in neonates. Hence, there is an urgent need for prophylactics to prevent viral transmission, especially from mother to fetus. HCMV glycoprotein B (gB) is both a key viral penetration protein and a dominant antigen for host defense. Unsurprisingly, gB is a component of all current HCMV vaccine candidates. However, vaccine efforts are stymied, at least in part, by an incomplete understanding of gB-specific immune responses. Moreover, the mechanistic contributions of gB to membrane fusion require further clarification. These gaps in our knowledge of both gB function and antigenicity largely stem from the reliance of research on the inactive, postfusion form of gB that cannot adequately recapitulate the active, prefusion form. We have successfully engineered soluble HCMV gB ectodomain in a prefusion form. Here, we propose to characterize its structure, antigenicity, and the mechanisms that control its activity. In Aim 1, we will determine the high-resolution structures of the prefusion HCMV gB and its complexes with known neutralizing antibodies. We will also stabilize prefusion gB for downstream applications (biochemical research and immunogen development). In Aim 2, we will isolate and characterize prefusion-gB-specific neutralizing antibodies from HCMV-seropositive donors. In Aim 3, we will investigate the regulatory mechanism that may restrain gB in its prefusion form. The proposal is innovative because, to our knowledge, this is the first time the soluble prefusion form of HCMV gB was successfully engineered. The proposal is significant because it will yield new mechanistic knowledge and provide new reagents that could aid in the development of optimal vaccines and passive immunization strategies against HCMV.

项目摘要/摘要 人类巨细胞病毒（HCMV）是一种非常成功的人类病原体，感染了世界的大部分 人口终身。虽然通常渐近造成HCMV感染，可能会引起严重的传播疾病 免疫功能低下的患者，例如，移植受者和新生儿的发展异常。 因此，迫切需要预防药物来防止病毒传播，尤其是从母亲到胎儿。 HCMV糖蛋白B（GB）既是一种关键的病毒渗透蛋白，也是用于宿主防御的主要抗原。 毫不奇怪，GB是所有当前HCMV疫苗候选物的组成部分。但是，疫苗的努力是 至少部分是由于对GB特异性免疫反应的不完全理解所困扰。而且， GB对膜融合的机械贡献需要进一步澄清。根据我们的知识这些差距 GB功能和抗原性都在很大程度上源于对灌肠后形式的研究的依赖 无法充分概括活跃的，预选形式的GB的GB。我们已经成功地设计了 可溶性HCMV GB外生域的诱发形式。在这里，我们建议表征其结构， 抗原性以及控制其活性的机制。在AIM 1中，我们将确定高分辨率 诱发HCMV GB及其复合物的结构具有已知中和抗体的结构。我们也会 稳定下游应用（生化研究和免疫原）的预选GB。在 AIM 2，我们将隔离并表征来自HCMV阳性的预灌注GB特异性中和抗体 捐助者。在AIM 3中，我们将调查可能以其预选形式限制GB的调节机制。这 提案具有创新性 成功地设计了。该提议很重要，因为它将产生新的机械知识和 提供可以帮助开发最佳疫苗和被动免疫的新试剂 针对HCMV的策略。