Optimizing Immunity and Maternal Host Defense Against Congenital Cytomegalovirus Infection

优化免疫和母体宿主防御先天性巨细胞病毒感染的能力

• 批准号: 10434692
• 负责人: ADAM P. GEBALLE
• 金额: $ 62.92万
• 依托单位: UNIVERSITY OF MINNESOTA
• 依托单位国家: 美国
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-09-01 至 2024-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10434692
• 关键词: Ablation; Adjuvant; Animals; Antibodies; Antigens; Antiviral Response; Attenuated; Attenuated Vaccines; Bacterial Artificial Chromosomes; Birth; Body Weight decreased; Cavia; Cell Culture Techniques; Cells; Clinical; Clinical Trials; Collaborations; Communicable Diseases; Complex; Contracts; Cyclic AMP-Dependent Protein Kinases; Cytomegalovirus; Cytomegalovirus Infections; Cytomegalovirus Vaccines; DNA biosynthesis; Development; Disabled Persons; Disease; Double-Stranded RNA; Enzyme-Linked Immunosorbent Assay; Equilibrium; Female of child bearing age; Gene Expression; Generations; Genes; Genome; Goals; Growth; Guinea pig cytomegalovirus; Host Defense; Human; Immediate-Early Proteins; Immune; Immune Evasion; Immune response; Immunity; Immunization; Immunize; Immunocompetent; Immunocompromised Host; Immunoglobulin G; Immunologics; Infant; Infection; Inflammatory; Interferon Type II; Interferons; Kinetics; Knock-out; Lead; Ligands; MF59; MHC Class I Genes; Modeling; Murid herpesvirus 1; Natural Immunity; Nucleic Acids; Pathogenesis; Pathway interactions; Pregnancy; Pregnancy Outcome; Pregnant Women; Preventive vaccine; Primary Infection; Production; Proteins; Recombinants; Role; Safety; Sensorineural Hearing Loss; Study models; Subunit Vaccines; Techniques; Testing; Uncertainty; United States; Vaccination; Vaccine Adjuvant; Vaccine Design; Vaccines; Vertical Disease Transmission; Viral; Viral Proteins; Viremia; Virulent; Virus; Virus Diseases; Virus Replication; Woman; Work; antagonist; attenuation; clinically relevant; congenital cytomegalovirus; congenital infection; cytokine; design; disability; enzyme linked immunospot assay; functional outcomes; guinea pig model; immunogenic; immunogenicity; immunoregulation; improved; in vivo; maternal vaccination; novel; overexpression; pregnant; prevent; programs; protective efficacy; protein kinase R; public health priorities; public health relevance; rational design; reconstitution; response; sensor; seropositive; transmission process; vaccine candidate; vaccine development; vaccine efficacy; vaccine immunogenicity; vaccine strategy

ABSTRACT Development of an effective preventative vaccine against human cytomegalovirus (HCMV) for women of childbearing age is a major public health priority. Subunit vaccines are in clinical trials, but uncertainty exists about optimal platforms and correlates of protection. Live, attenuated vaccines may induce a broader repertoire of immune responses, but striking the balance between safety and immunogenicity is challenging. The long-term goal of this ongoing collaboration is to use the guinea pig cytomegalovirus (GPCMV) model to test hypotheses about optimal design of safe and effective vaccines against congenital infection. We recently discovered that inclusion of a pentameric complex (PC), consisting of the GPCMV gH, gL and GP129, 131 and 133 (homologs of the HCMV PC), enabled generation of a live, attenuated vaccine that was protective against congenital GPCMV transmission, but the vaccine was unacceptably virulent. In parallel studies we observed that viral challenge of pregnant dams with preconception immunity to the prototypical GPCMV strain 22122 with a heterologous `clinical isolate', the CIDMTR strain, resulted in both maternal re-infection and congenital transmission of the new challenge strain. These findings, as well as clinical observations in HCMV-infected women, suggest that a vaccine may need to perform better than `natural immunity' in order to protect against reinfection. We hypothesize that a rationally designed, PC-intact, but disabled infectious single cycle (DISC) vaccine will provide superior protective immunity, including against re-infection, compared to subunit gB and to `natural' immunity. In Aim 1, we test this hypothesis by comparing a PC-positive vaccine, attenuated by deletions of GPCMV-encoded MHC I homologs and a viral protein kinase R (PKR) evasin, versus MF59- adjuvanted recombinant gB. We will examine the magnitude of protection after both primary maternal infection and re-infection of dams with preconception immunity following challenge with a heterologous strain during pregnancy. We will further optimize CMV vaccines in Aim 2 by developing DISC vaccines, using a PC-intact virus with destabilizing domains fused to essential viral proteins. In contrast to HCMV vaccines in clinical trials, we hypothesize that DISC vaccines in which viral replication is blocked downstream of DNA replication will progress to late gene expression and produce a broader array of immunogenic proteins. Aim 3 will evaluate whether deletion of viral antagonists of host cell defenses such as protein kinase R (PKR) can aid in vaccine design. We will test the hypothesis that GPCMV encodes a second PKR antagonist, elimination of which would be expected to generate a safe and effective vaccine. In addition, we will overexpress dsRNA in the vaccine construct with the aim of improving safety and immunogenicity. Vaccines will be evaluated for attenuation and immunogenicity and optimized vaccines will be used to identify immune correlates of protection, including non- neutralizing functions of IgG. Our studies will explore the overarching hypothesis that immunity conferred by a CMV vaccine can be superior to `natural' preconception immunity, a highly relevant issue for HCMV vaccines.

抽象的 开发针对人类巨细胞病毒（HCMV）的有效预防性疫苗 生育年龄是一个主要的公共卫生优先事项。亚基疫苗正在临床试验中，但存在不确定性 关于最佳平台和保护的关联。现场直播，减弱的疫苗可能会引起更广泛的 免疫反应的曲目，但是在安全性和免疫原性之间达到平衡是具有挑战性的。 这种持续合作的长期目标是将豚鼠巨细胞病毒（GPCMV）模型用于 测试有关针对先天性感染的安全有效疫苗最佳设计的假设。我们最近 发现包含五个五体络合物（PC），由GPCMV GH，GL和GP129、131和 133（HCMV PC的同源物），启用了一种可保护的活疫苗 先天性GPCMV的传播，但该疫苗是不可接受的毒气。在平行研究中，我们观察到 对原型GPCMV菌株22122的孕妇大坝的病毒挑战 CIDMTR菌株具有异源“临床分离株”，导致母体再感染和先天性 新挑战应变的传播。这些发现以及HCMV感染的临床观察结果 妇女，暗示疫苗可能需要比“自然免疫”更好地表现才能防止 重新感染。我们假设是一个理性设计的，PC-INTACT但残疾的传染性单周期（盘） 与亚基GB相比 “自然”免疫。在AIM 1中，我们通过比较PC阳性疫苗来检验该假设，并减弱 GPCMV编码的MHC I同源物和病毒蛋白激酶R（PKR）EVASIN的缺失，与MF59-- 辅助重组GB。我们将检查两种原发母亲感染后的保护幅度 并在挑战后与异源菌株抗衡的大坝再感染在 怀孕。我们将使用PC-INTACT开发圆盘疫苗，进一步优化AIM 2中的CMV疫苗 与必需病毒蛋白融合的不稳定结构域的病毒。与临床试验中的HCMV疫苗相反， 我们假设病毒复制被阻断DNA复制下游的椎间盘疫苗将 发展为晚期基因表达并产生更广泛的免疫原性蛋白。 AIM 3将评估 缺失宿主细胞防御的病毒拮抗剂（例如蛋白激酶R（PKR））是否可以帮助疫苗 设计。我们将测试GPCMV编码第二个PKR拮抗剂的假设 预计将产生安全有效的疫苗。此外，我们将过表达疫苗中的dsRNA 构建旨在提高安全性和免疫原性。疫苗将进行衰减和 免疫原性和优化疫苗将用于识别保护的免疫相关性，包括非 - 中和IgG的功能。我们的研究将探讨总体假设 CMV疫苗可以优于“天然”先入为主的免疫，这是HCMV疫苗的高度相关问题。