Rapid development and testing of Zika virus vaccine candidates

寨卡病毒候选疫苗的快速开发和测试

基本信息

批准号：
9330079
负责人：
PAULO H VERARDI
金额：
$ 19.23万
依托单位：
UNIVERSITY OF CONNECTICUT STORRS
依托单位国家：
美国
项目类别：
财政年份：
2016
资助国家：
美国
起止时间：
2016-08-15 至 2019-07-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/9330079
关键词：
Address Aedes Americas Animal Model Animals Antibiotics Antibody Formation Antibody titer measurement Antigens Biological Assay Brazil Cell Culture Techniques Cells Chikungunya virus Clinical Trials Country Culicidae Data Dengue Dengue Virus Development Disease Disease Outbreaks Electron Microscopy Flavivirus French Polynesia Genes Genome Goals Gold Growth Hemagglutination Heterophile Antigens Human Immunity Immunocompetent Immunocompromised Host In Vitro Interferon Receptor International Knockout Mice Link Membrane Membrane Proteins Methods Mexico Microcephaly Micronesia Modeling Modified Vaccinia Virus Ankara Mothers Mus Philippines Poxviridae Process Reporting Resistance SCID Mice Safety Serum Smallpox Smallpox Viruses Structure Testing Tetracyclines Vaccinated Vaccines Vaccinia virus Virus Diseases Virus-like particle Western Blotting Zika Virus Zika virus vaccine base cell mediated immune response design efficacy testing env Gene Products immunogenicity mouse model neutralizing antibody novel preclinical study protein expression public health emergency vaccine candidate vaccine development vaccine efficacy vaccinia virus vector vector viral vector development virus envelope

项目摘要

PROJECT SUMMARY Zika virus (ZIKV) is an enveloped flavivirus transmitted by Aedes mosquitos which leads to an asymptomatic or mild dengue-like disease. A large ZIKV outbreak started in Brazil in early 2015, recently spreading to more than 25 countries in the Americas. Alarmingly, the ZIKV Brazilian outbreak has been linked to thousands of microcephaly cases in babies born to infected mothers, leading the WHO to recently declare a Public Health Emergency of International Concern. Thus, control efforts are desperately needed to contain the outbreaks and avoid further spread to other countries. No ZIKV vaccines have been developed, although vaccines for the related dengue virus (DENV) based on the Membrane (M) and Envelope (E) proteins, which induce protective immunity, are in advanced clinical trials, and one (Dengvaxia) was just approved in Mexico, Brazil, and the Philippines. Vaccinia virus (VACV) was used to eradicate smallpox, a disease caused by variola virus, a related poxvirus. VACV has also been successfully used as a replication-competent or -defective viral vector for the development of effective human and animal vaccines, as it elicits strong and long-lasting humoral and cell-mediated immune (CMI) responses to heterologous antigens expressed in its genome. We recently generated VACV vectors with a built-in safety mechanism that replicate only in the presence of tetracycline antibiotics. When administered as a vaccine (in the absence of antibiotics), the vector does not replicate but retains its immunogenicity, and therefore is safer for human use. Conveniently, the vector can be propagated in cell culture at high titers in the presence of tetracyclines, unlike other replication-defective VACV-based vectors such as modified vaccinia Ankara (MVA). More recently, we developed a novel method to generate and purify recombinant VACV vaccines without the use of selection markers in as little as one week, a process that normally takes months. Our goal is to use this method to rapidly generate recombinant VACV vaccines expressing the ZIKV E and M proteins and to test their immunogenicity, safety, and efficacy in mice. In Aim 1 we will rapidly generate and characterize replication-defective VACV vaccine candidates expressing the ZIKV E protein (VACV-ZIKVs). A number of ZIKV E and M-E gene constructs were designed for expression of E alone or as virus-like particles (VLPs) to maximize induction of serum neutralizing (SN) antibodies. In Aim 2 we will test the immunogenicity (SN titers and CMI responses) and safety of VACV-ZIKV vaccine candidates in mice. Concurrently, in Aim 3 we will develop a ZIKV mouse challenge model based on current models for the related DENV to test the efficacy of our VACV-ZIKV vaccine candidates. Our goal is to use our accelerated VACV platform to rapidly select the best antigen strategy that leads to high levels of SN antibody production, CMI responses, and protection in mice.

项目概要寨卡病毒 (ZIKV) 是一种由伊蚊传播的有包膜黄病毒，可导致无症状或轻度登革热样疾病。 2015 年初，巴西爆发了大规模 ZIKV 疫情，最近传播到美洲超过25个国家。令人担忧的是，巴西 ZIKV 疫情已与受感染母亲所生婴儿的数千例小头畸形病例有关，导致世界卫生组织最近宣布国际关注的突发公共卫生事件。因此，控制努力是迫切需要控制疫情并避免进一步蔓延到其他国家。没有寨卡病毒尽管针对相关登革热病毒（DENV）的疫苗是基于诱导保护性免疫的膜 (M) 和包膜 (E) 蛋白处于高级临床阶段试验中，其中一种（Dengvaxia）刚刚在墨西哥、巴西和菲律宾获得批准。牛痘病毒（VACV）用于根除天花，这是一种由天花病毒（一种相关的痘病毒）引起的疾病。疫苗接种有也已成功用作复制能力或缺陷型病毒载体，用于开发有效的人类和动物疫苗，因为它能引发强烈且持久的体液和细胞介导的疫苗对其基因组中表达的异源抗原的免疫（CMI）反应。我们最近生成了具有内置安全机制的 VACV 载体仅在四环素存在的情况下才能复制抗生素。当作为疫苗施用时（在没有抗生素的情况下），载体不会复制但保留了其免疫原性，因此对人类使用更安全。方便地，向量可以是与其他复制缺陷型细胞不同，在四环素存在的情况下在细胞培养物中以高滴度繁殖基于 VACV 的载体，例如改良的安卡拉痘苗病毒 (MVA)。最近，我们开发了一本小说不使用选择标记来产生和纯化重组 VACV 疫苗的方法短短一周，这一过程通常需要几个月的时间。我们的目标是利用这种方法快速生成表达 ZIKV E 和 M 蛋白的重组 VACV 疫苗并测试其效果小鼠的免疫原性、安全性和有效性。在目标 1 中，我们将快速生成并表征表达 ZIKV E 蛋白（VACV-ZIKV）的复制缺陷型 VACV 候选疫苗。一个数字 ZIKV E 和 M-E 基因构建体被设计用于单独表达 E 或作为病毒样颗粒表达（VLP）以最大限度地诱导血清中和（SN）抗体。在目标 2 中，我们将测试 VACV-ZIKV 候选疫苗在小鼠体内的免疫原性（SN 滴度和 CMI 反应）和安全性。同时，在目标 3 中，我们将基于当前模型开发 ZIKV 小鼠挑战模型相关 DENV 来测试我们的 VACV-ZIKV 候选疫苗的功效。我们的目标是利用我们的加速 VACV 平台，快速选择导致高水平 SN 的最佳抗原策略小鼠体内的抗体产生、CMI 反应和保护。