A novel cholera subunit vaccine based on 4 colonization factors

描述(由申请人提供)：根据目前对霍乱弧菌(VC)定植、发病机制和人类对霍乱的免疫反应的了解，提出了一种开发霍乱亚单位疫苗的新方法。目前，在霍乱问题严重的世界大部分地区使用口服灭活的全细胞(W-C)VC疫苗。它所产生的保护程度取决于接种者的年龄和以前接触VC的情况。灭活的W-C霍乱疫苗不表达感染期间表达的几种VC保护性抗原的免疫原性水平。为了避免这一点，我们提出了一种策略，部分基于非常成功的b型和b型流感嗜血杆菌百日咳疫苗，这种疫苗利用与载体蛋白结合的碳水化合物表位，或者多种毒力因子和一种毒素来实现长期免疫。在动物模型中，抗VC-LPS的单抗和3种定植因子具有保护性作用。这些VC毒力因子将被用来配置霍乱亚单位疫苗，以诱导对VC致病关键第一步(S)的集中免疫反应。我们推测，由4个保护性VC定植/黏附因子组成的亚单位霍乱疫苗可诱导1剂保护性免疫。解毒的稻叶内毒素将与三种毒力因子之一偶联：毒素共调节菌毛A(TCPA)、TcpF或几丁质结合蛋白A(CBP-A)。携带者特异性T细胞帮助增强抗内毒素反应，并有助于诱导保护性携带者特异性抗体。这些研究将在霍乱研究方面拥有丰富经验的韦德和格兰杰博士聚集在一起。W.Wade博士接受过免疫病理方面的培训。他率先开发了合成VC-内毒素表位与载体蛋白结合的疫苗接种方案。他是抗VC内毒素反应方面的专家。格兰杰博士是一位颇有成就的碳水化合物化学家，他制造出了VC-LPS：蛋白质结合物。公共卫生相关性：霍乱仍然是一种每年导致数百万人患病和数千人死亡的疾病。我们建议基于霍乱弧菌毒力蛋白TcpA的保护性表位的鉴定来研制一种新的亚单位霍乱疫苗。我们实验室以前的工作表明，内毒素和三氯甲烷可以形成霍乱疫苗的基础。我们将致力于开发一种霍乱亚单位疫苗，其基础是解毒的内毒素结合到引起当前大流行的霍乱弧菌株定植所需的3个蛋白质组分。

DESCRIPTION (provided by applicant): A novel approach is proposed to develop a cholera subunit vaccine based on the current understanding of Vibrio cholerae (Vc) colonization, pathogenesis, and the human immune response to cholera. Currently, a killed, whole-cell (W-C) Vc vaccine delivered orally is used in much of the world where cholera is problematic. The degree of protection it induces depends on the age and the previous exposure of the vaccinees to Vc. The killed W-C cholera vaccines do not express immunogenic levels of several Vc protective antigens that are expressed during infection. To circumvent this, we propose a strategy based in part on the highly successful H. influenzae type b and B. pertussis vaccines that utilize either carbohydrate epitopes bound to carrier proteins, or multiple virulence factors and a toxoid to achieve long-lasting immunity. Individual antibodies (Abs) to Vc LPS and 3 colonization factors are protective in animal models. These Vc virulence factors will be used to configure a cholera subunit vaccine to induce a concentrated immune response to the critical first step(s) in Vc pathogenesis. We hypothesize that a subunit cholera vaccine, composed of 4 protective Vc colonization/adhesion factors will induce protective immunity with 1 dose. Detoxified (det) Inaba LPS will be conjugated to one of three virulence factors: Toxin Co-Regulated pilus A (TcpA), TcpF or chitin-binding protein A (CBP-A). Carrier-specific T cell help will enhance the anti-LPS response and help for induction of protective carrier-specific Abs. The studies bring together Drs. Wade and Grandjean who have extensive experience in cholera research. Dr. W. Wade is trained in immunopathogenesis. He pioneered the development of the vaccination protocols for synthetic Vc LPS epitopes conjugated to carrier proteins. He is an expert in the anti-Vc LPS response. Dr. Grandjean is an accomplished carbohydrate chemist who has generated Vc LPS:protein conjugates. Public Health Relevance: Cholera is still a disease that sickens millions and kills thousands yearly. We propose to formulate a new subunit cholera vaccine based on identification of protective epitopes in a known virulence proteins of V. cholerae: TcpA. Previous work from our lab has shown that LPS and TcpA can form the basis for a cholera vaccine. We will pursue the development of a cholera subunit vaccine based on detoxified-LPS bound to 3 protein component required for colonization of the strain of V. cholera that is causing the current pandemic.