A novel strategy for developing a SARS-CoV vaccine

项目概要/摘要 项目概要：由新型冠状病毒引起的严重急性呼吸系统综合症 （SARS-CoV），导致2002-2003年的发病率和死亡率很高。与缺乏 由于SARS复发，研制有效疫苗的研究工作基本上已经停止。 然而，已经在蝙蝠和其他动物中发现了与SARS-CoV相似的冠状病毒， 中国的人口，使SARS复发的可能性。因此，我们认为， 现在研发疫苗还为时过早。我们的目标是开发一个安全的， SARS-CoV免疫原性减毒活疫苗。在初步结果中，我们描述了 我们认为是第一个候选的减毒活疫苗。这种重组病毒缺乏 包膜（E）蛋白的表达，这导致减毒病毒， 在表达SARS-CoV受体（人）的转基因仓鼠或小鼠中的疾病 血管紧张素转化酶，hACE 2），但当用于免疫这些动物时， 对野生型SARS-CoV攻击的部分保护。其核心目标是 一项新的研究计划是开发表达突变E蛋白的新型SARS-CoV减毒活疫苗 因此它们比E-缺失病毒更具免疫原性，但仍然安全。这一目标将 1）优化rSARS-CoV-E的免疫原性 病毒通过突变而不是删除E蛋白。在这个目标下，我们将描绘不同的 负责其各种生物活性的E蛋白区域。2)去培养一只老鼠- 用修饰的E蛋白表达改造rSARS-CoV，以开发rSARS-CoV-E 缺乏一种或多种辅助蛋白的表达，并确定 组织培养传代后rSARS-CoV-E的保护能力增强。老鼠- 适应性SARS-CoV导致肺部疾病。我们将开发重组病毒， 在此背景下表达突变的E蛋白。我们还将通过变异来优化疫苗 基因组的其他部分。3)为了检测SARS-CoV-E和表达突变E的病毒， 候选疫苗作为这一目标的一部分，将确定保护的免疫相关性。 我们还将对病毒进行额外的修饰， 环境中的冠状病毒不太可能。

PROJECT SUMMARY/ABSTRACT Project Summary: The Severe Acute Respiratory Syndrome, caused by a novel coronavirus (SARS-CoV), resulted in substantial morbidity and mortality in 2002-2003. With the lack of recurrence of SARS, research efforts to develop an effective vaccine have largely halted. However, coronaviruses similar to SARS-CoV have been identified in bats and other animal populations in China, making recurrence of SARS a possibility. Thus, we believe that cessation of efforts to develop a vaccine is premature. Our goal in this proposal is to develop a safe and immunogenic live attenuated vaccine for SARS-CoV. In preliminary results, we describe what we believe is the first candidate live attenuated vaccine. This recombinant virus lacks expression of the envelope (E) protein, which results in an attenuated virus that causes no disease in either hamsters or mice transgenic for expression of the SARS-CoV receptor (human angiotensin converting enzyme, hACE2) but when used to immunize these animals, provided partial protection against challenge with wild type SARS-CoV. The central objective of this proposal is to develop novel live attenuated SARS-CoV vaccines that express mutated E protein so that they are more immunogenic than E-deleted virus but remain as safe. This objective will be achieved in the following specific aims: 1) To optimize immunogenicity of rSARS-CoV-¿E virus by mutating rather than deleting the E protein. In this aim, we will delineate different regions of the E protein responsible for its various biological activities. 2) To develop a mouse- adapted rSARS-CoV with modified E protein expression, to develop rSARS-CoV-¿E lacking expression of one or more accessory proteins and to determine the basis of enhanced protective ability of rSARS-CoV-¿E after tissue culture passage. Mouse- adapted SARS-CoV causes pulmonary disease. We will develop recombinant viruses that express mutated E protein on this background. We will also optimize the vaccine by mutating other parts of the genome. 3) To test SARS-CoV-¿E and viruses expressing mutated E as vaccine candidates. As part of this aim, immune correlates of protection will be determined. We will also introduce additional modifications to the virus to make recombination with coronaviruses in the environment unlikely.