VIBRIO CHOLERAE TCP AND LPS SUBUNIT VACCINE, EPITOPES AN

霍乱是一种由革兰氏阴性菌霍乱弧菌引起的急性腹泻疾病。在摄入受污染的食物或水后，细菌在小肠上定居并分泌霍乱毒素，这是感染者体液和电解质大量流失的原因。霍乱仍然是一个世界性的问题。尽管已经对一些活的、减毒的或灭活的全细胞疫苗配方进行了测试，但没有一种被证明足够成功，足以导致它们的广泛使用。这项赠款建议侧重于根据目前对霍乱弧菌定植、发病机制和人类对感染的免疫反应的了解，开发霍乱亚单位疫苗配方的新方法。该战略将纳入非常成功的b型流感嗜血杆菌和百日咳疫苗的特点，这些疫苗利用明确的表面毒力决定因素、定植因子和毒素来实现长期保护。目前的提案将重点放在包括毒素共调节菌毛(TCP)定植因子、解毒内毒素和佐剂霍乱毒素的配方上。这些研究的总体目标是确定提供保护性体液反应的TCP和LPS抗原的最有效组合。我们将详细描述这些抗原的B细胞表位，并确定哪些表位是有效免疫所需的最低要求。研究将把这一信息扩展到人类血清中，并证明我们已经确定的表位在该领域是可行的。使用建立良好的小鼠模型，我们将很快能够确定可能扩展到人体试验的免疫方案和免疫原。这项拟议的研究正式汇集了达特茅斯医学院两个研究小组的专业知识。威廉·韦德博士是一名分子免疫学家，曾接受过与抗原呈递相关的蛋白质结构和功能分析方面的培训。他的研究重点是优化免疫原性和抗原传递的方法。罗纳德·泰勒博士的研究重点是霍乱弧菌致病的分子基础。他发现，tcp和他的团队在表征tcpa基因和相应的菌毛蛋白方面发挥了重要作用，并证明tcp是霍乱弧菌的主要定植因子和保护性抗原。这两个研究小组的专业知识结合在一起，将为使用新方法开发和评估V：霍乱亚单位疫苗提供一个独特的机会。

Cholera is an acute diarrheal disease caused by the gram-negative bacterium, Vibrio cholerae. Following ingestion of contaminated food or water, bacteria colonize the small intestine and secrete cholera toxin, which is responsible for the extensive loss of fluid and electrolytes from infected individuals. Cholera remains a worldwide problem. Although a number of live, attenuated or killed whole cell vaccine formulations have been tested, none have proven successful enough to result in their widespread use. This grant proposal focuses on new approaches to develop a cholera subunit vaccine formulation based on the current understanding of V. cholerae colonization, pathogenesis, and human immune responses to infection. The strategy will incorporate features of the highly successful Haemophilus influenzae type b and pertussis vaccines that utilize defined surface virulence determinants, colonization factors, and toxoids to achieve long-lasting protection. The present proposal will focus on formulations that include the toxin coregulated pilus (TCP) colonization factor, detoxified LPS, and the adjuvant cholerae toxin. The general goal for these studies is to define the most effective combination of TCP and LPS antigens that provide for protective humoral responses. We will characterize in detail the B cell epitopes for these antigens and determine which epitopes are minimally required for effective immunity. Studies will extend this information to human sera and demonstrate that the epitopes we have identified are operational in the field. Using a well- established mouse model, we will quickly be able to define the immunization regimen and immunogens that are likely candidates for extension into human trials. The proposed research formally brings together the expertise from two research groups at Dartmouth Medical School. Dr. William Wade is a molecular immunologist with training in structural and functional analyses of proteins as they relate to antigen presentation. His research focuses on methodologies to optimize the immunogenicity and delivery of antigens. Dr. Ronald Taylor's research focuses on the molecular basis of V. cholerae pathogenesis. He discovered TCP and his group has been instrumental in characterizing the tcpA gene and corresponding pilin protein as well as demonstrating that TCP is the major V. cholerae colonization factor and a protective antigen. Together, the expertise of these two research groups will provide a unique opportunity to develop and evaluate V: cholerae subunit vaccines using new approaches.