Revolutionary Eilat-based Chikungunya Vaccine Vector

摘要 传统上，病毒疫苗涉及安全性和免疫原性之间的权衡，这尤其是在疫苗的安全性和免疫原性之间。 控制爆发性新疾病所需的疫苗具有挑战性， 免疫力至关重要。为了克服这些挑战，我们开发了一种蚊子特异性甲病毒，埃拉特病毒 （EILV）作为一种革命性的新型疫苗载体。埃拉特在蚊子细胞中复制到非常高的滴度， 由于进入和RNA的基本限制， 复制的我们用基孔肯雅病毒的囊膜蛋白构建了EILV嵌合cDNA （CHIKV），这是负责重大重新出现的衰弱，慢性关节痛的爆发， 数百万人，最近几乎影响到美洲所有国家。最近，一种CHIKV疫苗 将其列为全球疫苗需求的第二优先事项。在初步研究中，嵌合EILV/CHIKV疫苗 候选物在单次给药后针对小鼠攻击提供了快速和持久的保护， 非人类灵长类动物我们将进一步开发这种嵌合体，并检验基于EILV的嵌合体 病毒可以作为“假灭活”甲病毒疫苗，使用三个目的： 1.优化EILV/CHIKV嵌合疫苗的复制和免疫原性，确认其安全性 （包括明确证明脊椎动物细胞中缺乏RNA复制），验证有效 在无血清培养基中生产，并开发廉价的纯化方法。 2.研究优化的EILV/CHIKV疫苗在小鼠中的保护效力，了解免疫效果 宿主保护机制，包括先天性和适应性免疫反应的表征， 接种和攻击小鼠，并确定宿主保护的免疫相关性。 3.优化EILV/CHIKV疫苗的剂量，并确认其快速和长效免疫原性， 保护食蟹猴。这些结果将与灭活和减毒活疫苗进行比较。 CHIKV疫苗。 其结果将是一种安全、有效、廉价的单剂CHIKV疫苗，可提供快速且长效的治疗 保护，以及可以应用于所有其他致病性甲病毒的平台技术， 委内瑞拉和东部马脑炎病毒，以及最近出现的马亚罗病毒。这些疫苗 将非常适合控制通常影响资源贫乏的热带国家的爆炸性疾病爆发。 了解这种疫苗显著免疫原性的机制研究也将影响其他疫苗。 疫苗设计平台，通过剖析病毒疫苗的基本组成部分， 保护性免疫反应的各个分支。

ABSTRACT Traditionally, viral vaccines have involved trade-offs between safety and immunogenicity, which is especially challenging for vaccines needed to control explosive emerging diseases where rapid protection and durable immunity are crucial. To overcome these challenges, we developed a mosquito-specific alphavirus, Eilat virus (EILV), as a revolutionary new vaccine vector. Eilat replicates to exceptionally high titers in mosquito cells but is completely defective for replication in vertebrate cells due to fundamental restrictions in entry and RNA replication. We generated a chimeric EILV cDNA with envelope proteins derived from chikungunya virus (CHIKV), which is responsible for major reemerging outbreaks of debilitating, chronic arthralgia involving millions of persons and recently affecting nearly all countries in the Americas. A CHIKV vaccine was recently ranked the #2 priority for global vaccine needs. In preliminary studies, the chimeric EILV/CHIKV vaccine candidate provided rapid and durable protection following a single dose against challenge of mice and nonhuman primates. We will further develop this chimera and test the hypothesis that EILV-based chimeric viruses can serve as “pseudoinactivated” alphavirus vaccines, using three Aims: 1. Optimize the replication and immunogenicity of the chimeric EILV/CHIKV vaccine, confirm its safety (including unambiguously demonstrating a lack of RNA replication in vertebrate cells), verify efficient production in serum-free media, and develop inexpensive purification methods. 2. Study the protective efficacy of the optimized EILV/CHIKV vaccine in mice and understand the immune mechanisms of host protection, including characterization of innate and adaptive immune responses in vaccinated and challenged mice, and determination of the immune correlates of host protection. 3. Optimize the dosage of the EILV/CHIKV vaccine and confirm its rapid and long-lived immunogenicity and protection in cynomolgus macaques. These outcomes will be compared to inactivated and live-attenuated CHIKV vaccines. The result will be a safe, efficacious, inexpensive single-dose CHIKV vaccine that provides rapid and long-lived protection, as well as a platform technology that can be applied to all other pathogenic alphaviruses such as Venezuelan and Eastern equine encephalitis viruses, and the recently emerging Mayaro virus. These vaccines will be ideally suited for controlling explosive outbreaks that typically affect resource-poor tropical countries. The mechanistic studies to understand the remarkable immunogenicity of this vaccine will also impact other vaccine design platforms by dissecting the fundamental components of a viral vaccine required to induce various arms of the protective immune response.