Bacteriophage virus-like particle vaccines against dengue virus non-structural protein 1

项目总结 登革热病毒(DENV)是一种蚊媒黄病毒，每年感染全球超过3.9亿人， 主要是在发展中国家。目前还没有针对DENV的抗病毒治疗，预防工作依赖于 关于蚊子媒介埃及伊蚊的局部控制。尽管开发DENV疫苗的努力一直在进行 经过80多年的努力，一种安全有效的疫苗仍然难以找到，这主要是由于这种独特的致病菌 登革热病毒感染的特点。最近对登革热(赛诺菲巴斯德)安全性的担忧 强调了新的DENV疫苗战略的必要性。几个组织的最新研究表明 与病毒非结构蛋白1(NS1)参与血管渗漏的发生和进展有关 严重的疾病。NS1在感染早期产生，并从受感染的细胞大量分泌到 血液通过破坏血管系统中的内皮细胞而导致血浆泄漏， 通过与内皮细胞直接相互作用以及通过诱导免疫细胞间接作用来介导 产生导致血浆渗漏的细胞因子。事实上，用重组NS1蛋白或修饰的NS1蛋白免疫 NS1蛋白可以保护NS1介导的血管渗漏。然而，一些抗体产生了 抗NS1与内皮细胞和血小板上的宿主蛋白有交叉反应，这被认为是 进一步促进宿主的致病作用。出于这个原因，NS1是一个很有希望的DENV候选者 疫苗，但出于安全原因，应注意避免引发潜在的有害自身反应 抗体。在这里，我们建议使用高度免疫原性的噬菌体病毒样颗粒(VLP)平台来 展示短NS1多肽作为一种新的疫苗策略。这种方法有望激发出高滴度， 针对不会引起危险交叉反应的表位的针对NS1的长效抗体 抗体。在目标1中，我们将设计基于VLP的噬菌体免疫原，并免疫小鼠以诱导 抗体。在目标2中，我们将评估我们的噬菌体所激发的抗体的结合特性。 显示NS1多肽的VLP。在目标3中，我们将对由 候选疫苗，包括它们阻止NS1介导的内皮细胞破坏和免疫细胞的能力 细胞因子的产生。在目标4中，我们将使用小鼠对我们的候选疫苗进行体内评估 登革热病毒病模型。总体而言，这些研究将确定表位特异性抗体的功能 并导致针对NS1的疫苗的鉴定，以产生保护性和安全的抗体 回应。

PROJECT SUMMARY Dengue virus (DENV) is a mosquito-borne flavivirus that infects over 390 million people worldwide annually, primarily in developing nations. There are currently no antiviral treatments for DENV and prevention efforts rely on local control of the mosquito vector, Aedes aegypti. Although efforts to develop a DENV vaccine have been pursued for over 80 years, a safe and effective vaccine remains elusive largely due to the unique pathogenic features of DENV infection. Recent concerns regarding the safety of Dengvaxia (Sanofi Pasteur) has highlighted the need for novel vaccine strategies for DENV. Recent research from several groups has implicated the viral non-structural protein 1 (NS1) in the development of vascular leakage and progression to severe disease. NS1 is produced early in infection and is secreted in large quantities from infected cells into the blood where it goes on to cause plasma leakage by disruption of endothelial cells in the vasculature, mediated through direct interaction with endothelial cells and also indirect action by eliciting immune cells to produce cytokines that cause plasma leakage. Indeed, immunization with recombinant NS1 protein or modified NS1 proteins can protect against NS1-mediated vascular leakage. However, some antibodies produced against NS1 have cross-reactivity to host proteins on endothelial cells and platelets, which are hypothesized to further contribute to pathogenesis in the host. For this reason, NS1 is a promising candidate for a DENV vaccine, but for safety reasons care should be taken to avoid eliciting potentially harmful auto-reactive antibodies. Here, we propose to use highly immunogenic bacteriophage virus-like particle (VLP) platforms to display short NS1 peptides as a novel vaccine strategy. This approach holds promise for eliciting high-titer, long-lasting antibodies against NS1 that are specific for epitopes that do not elicit dangerous cross-reactive antibodies. In Aim 1, we will engineer bacteriophage VLP-based immunogens and immunize mice to elicit antibodies. In Aim 2, we will assess the binding characteristics of antibodies elicited by our bacteriophage VLPs displaying NS1 peptides. In Aim 3, we will perform in vitro assessments of the antibodies elicited by the vaccine candidates, including their ability to block NS1-mediated endothelial cell disruption and immune-cell cytokine production. In Aim 4, we will perform an in vivo assessment of our vaccine candidates using a mouse model of dengue virus disease. Overall these studies will establish the functions of epitope-specific antibodies against NS1 and lead to the identification of vaccines against NS1 for eliciting protective and safe antibody responses.