Attenuated Live and Recombinant Yersinia pestis Vaccines

描述（由申请人提供）：鼠疫耶尔森氏菌在三次大流行中造成约2亿人死亡，并且仍然在世界各地流行，造成零星感染。由于鼠疫不能腐生，并且在许多啮齿动物种群中存在，它是由动物-人类专性病原体引起的最令人恐惧的人畜共患疾病之一。鼠疫杆菌至少在800年前就开始被用作生物武器，而今天它是一种更有可能的生物威胁。基于上述考虑，我们提出：(1)在小鼠口服免疫后，构建并评价合成鼠疫杆菌K1M抗原的鼠伤寒沙门氏菌重组减毒疫苗（RASV），以鉴定能刺激保护性免疫以对抗致病性鼠疫杆菌K1M的抗原。（ii）构建并评估具有RpoS*表型的重组减毒伤寒沙门氏菌ISP1820，以传递一种或多种具有保护性的鼠疫杆菌KIM抗原。如果发现需要不同的抗原递送模式来诱导对鼠疫杆菌的保护性免疫，我们将构建所有被认为必要的重组疫苗作为鸡尾酒给药。（iii）构建并评估一种鼠疫杆菌减毒活疫苗，该疫苗将诱导对鼠疫杆菌用于获取铁（一种重要的毒力属性）的大多数（如果不是全部）蛋白质的增强免疫反应，并表现出完全的生物遏制作用，由于阿拉伯糖调节的延迟细胞裂解系统，在十代生长后没有存活的细菌细胞。我们将开始构建缺乏70kb Lcr质粒且完全无毒的鼠疫菌KIM6+，并在引入减毒突变后重新加入Lcr质粒。我们还将开发我们的主文件，准备和充分表征候选疫苗主种子的稳定性和安全性，准备和提交IRB批准的方案，提交获得ind所需的信息，并执行任何其他必要的工作，以安排最佳候选疫苗在人类志愿者中进行临床评估。

DESCRIPTION (provided by applicant): Yersinia pestis, in three pandemics, resulted in some 200 million plague deaths and is still endemic throughout the world resulting in sporadic infections. Due to its inability to lead a saprophytic life and its residence in many rodent populations, plague is one of the most feared of zoonotic diseases caused by an obligate animal-human pathogen. The plague bacillus began to be used as a biological weapon at least 800 years ago and is today one of the more likely biological threats. Because of these considerations, we propose to: (i) Construct and evaluate recombinant attenuated Salmonella typhimurium vaccines (RASV) synthesizing Y. pestis K1M antigens in vivo after oral immunization of mice to identify antigens that stimulate protective immunity to challenge with virulent Y. pestis K1M. (ii) Construct and evaluate a recombinant attenuated S. typhi ISP1820 with an RpoS* phenotype to deliver one or more protective Y. pestis KIM antigens. If it is found that different antigen delivery modes are required to induce protective immunity to Y. pestis challenge, we will construct all deemed necessary recombinant vaccines to be administered as a cocktail. (iii) Construct and evaluate a live attenuated Y. pestis vaccine that will induce enhanced immune responses to most, if not all, proteins used by Y. pestis to acquire iron, an important virulence attribute, and exhibit complete biological containment with no surviving bacterial cells after ten generations of growth due to an arabinose-regulated delayed cell lysis system. We will initiate our construction endeavors with Y. pestis KIM6+ that lacks the 70 kb Lcr plasmid and is totally avirulent and add back the Lcr plasmid after introducing attenuating mutations. We will also develop our Master File, prepare and fully characterize candidate vaccine Master Seeds for stability and safety, prepare and submit protocols for IRB approvals, submit information necessary to obtain INDs, and perform any other work needed to arrange that the best candidate vaccines be clinically evaluated in human volunteers.