A novel vaccine: botulinum neurotoxin subunit on a viral carrier.

描述(申请人提供)：根据NIAID关于肉毒杆菌中毒的情况说明书，“肉毒杆菌神经毒素(BONT)的极端毒性以及生产、运输和交付的简便性使其成为引起极端生物恐怖主义关注的制剂。”尽管如此，尽管目前正在进行重大疫苗开发活动，但目前还没有获得批准的肉毒毒素疫苗。肉毒杆菌研究的进展表明，疫苗开发的最佳靶点是毒素重链(HC50)的无毒羧基末端。事实上，NIAID的一个直接研究目标是开发一种针对肉毒杆菌的HC50片段疫苗。基于本项目第一阶段概念验证研究的令人鼓舞的数据，第二阶段的总体目标是开发一种针对最常见的A型、B型和E型的新的三价肉毒杆菌疫苗。为进一步开发这种新型三价BONT疫苗提出了如下三个目标：具体目标1：疫苗载体的构建和回收。I)质粒构建，ii)细胞表面表达Bont HC50，以及iii)从Vero上的cDNA中回收重组RV。具体目的2.疫苗载体特性I)轮状病毒病毒粒子的纯化、灭活和体外特性，II)使用ELISA法、体外中和试验分析小鼠对疫苗的免疫应答，以及依赖于所使用的免疫疫苗(S)对小鼠抵抗BONT单次攻击或多重BONT攻击的体内保护。具体目标3：开发中试生产和提纯工艺。这一目标的总体目标是将我们疫苗的生产过程从研究环境转变为适合中试规模疫苗生产的过程。 公共卫生相关性：这项研究项目与公共卫生直接相关，因为它旨在开发一种安全有效的肉毒杆菌神经毒素疫苗。肉毒杆菌毒素因其极强的效力和致命性以及易于生产和运输而成为生物武器的主要威胁。目前正在研究的肉毒毒素疫苗需要多次加强才能产生不是很高的效价，这突显了改进肉毒毒素疫苗的必要性。目前尚不清楚目前的肉毒杆菌疫苗是否能保护 正如疾控中心疫苗同意书上的免责声明所指出的：“……，但仍然需要其他个人保护措施。你应该认为个人保护措施是目前针对任何这些细菌(原文如此)毒素的唯一保护措施。”

DESCRIPTION (provided by applicant): According to the NIAID fact sheet on Botulism, "the extreme toxicity of botulinum neurotoxins (BoNT) and the ease of production, transport, and delivery make this an agent of extreme bioterrorism concern." Nonetheless, although there are major vaccine development initiatives ongoing, there currently is no approved Botulinum toxin vaccine available. Advances in Botulinum research have designated the optimal target for vaccine development to be the non-toxic carboxyterminal half of the toxin heavy chain (HC50). In fact, an immediate research goal for NIAID is listed as the development of a HC50 fragment vaccine against botulinum. Building upon the encouraging data from the phase I proof of concept study of this project, the overall phase II project goal is to develop a new, trivalent botulinum vaccine against the most common serotypes A, B and E. Three Aims are proposed for the further development of this novel trivalent BoNT vaccine as follows: Specific Aim 1: Vaccine vector construction and recovery. i) plasmid constructions, ii) demonstration of cell surface expression of the BoNT HC50, and iii) re-recovery of recombinant RVs from cDNA on Vero. Specific Aim 2. Vaccine vector characterization i) purification, inactivation, and in vitro characterization of the RV virions, ii) analysis of mouse immune responses to the vaccine using ELISA, in vitro neutralization assays, and in vivo protection of mice against a single challenge with BoNT or multiple BoNT challenge dependent on the used vaccine(s) for immunization. Specific Aim 3: Development of Pilot Production and Purification Processes. The overall goal of this aim is to translate the production process of our vaccine from a research setting to one suitable for pilot scale vaccine manufacture. PUBLIC HEALTH RELEVANCE: This research project is directly relevant to public health in that it is directed towards the development of a safe and effective vaccine for Botulinum neurotoxin. Botulinum toxin posesa major bioweapon threat because of its extreme potency andlethality and its ease of production and transport. A current investigational botulinum- toxoid vaccine requires multiple boosts to generate titers that are not very high, highlighting the need for an improved botulinum toxin vaccine. It is unclear if the current Botulinum vaccine protects at all as indicated by the disclaimer on the CDC vaccine consent form: "..., but other personal protective measures are still required. You should think of personal protective measures as the only protective measure against any of these bacteria (sic) toxins at this time."