Innate and early B cell responses to V. cholerae

项目摘要 霍乱仍然是导致疟疾的一个重要原因，最近在非洲大陆出现的霍乱就是证明。 海地地震科学和政策领导人越来越多地呼吁使用预防战略， 作为疫苗接种霍乱等霍乱疾病，但目前的霍乱疫苗受到免疫学 局限性。最重要的是，口服霍乱疫苗产生的保护作用持续时间短-与自然免疫相反， 感染霍乱弧菌，从而诱导持久的免疫力。 在这里提出的研究中，我们试图确定先天和B细胞中最早的差异， 自然感染与霍乱疫苗接种后的免疫反应。我们还旨在确定其中哪些 早期差异对于随后的长期免疫记忆的发展是最关键的。 了解这些早期差异可以解释为什么只有自然感染霍乱弧菌才会引起 长期记忆B细胞反应，这对预防霍乱很重要。 由于霍乱弧菌是一种人类限制性病原体，因此临床研究对于解决这一问题至关重要 问题我们建议利用现有的合作，马萨诸塞州一般 医院/哈佛医学院（MGH/HMS），国际腹泻病研究中心， 孟加拉国（ICDDR，B）、埃默里疫苗中心和麻省理工学院/哈佛大学布罗德研究所， 在人类身上解决这个问题。具体来说，我们将比较先天免疫反应的激活， 粘膜组织后，霍乱感染与疫苗接种，我们将评估这些差异 与霍乱患者的长期记忆B细胞反应相关。我们还将比较抗体分泌 细胞（ASC）的反应。免疫球蛋白基因的克隆和这些基因的产生 从单个ASCs克隆抗体可能会提高我们对B细胞反应差异的理解 霍乱患者和疫苗接种者之间的关系，产生的抗体也可能提供工具， 诊断和治疗潜力。这些研究将通过以下方式提高我们对这些机制的理解： 粘膜表面的先天性免疫应答促进了持久的免疫， 改进现有霍乱疫苗的战略。

PROJECT SUMMARY Cholera remains an important cause of diarrheal illness, as evidenced by its recent emergence in post- earthquake Haiti. Scientific and policy leaders are increasingly calling for the use of preventive strategies such as vaccination for diarrheal diseases like cholera, but current cholera vaccines suffer from immunologic limitations. Most importantly, oral cholera vaccines elicit protection of short duration -- in contrast to natural infection with V. cholerae, which induces long-lasting immunity. In the research proposed here, we seek to identify the earliest differences in the innate and B cell immune responses after natural infection versus cholera vaccination. We also aim to identify which of these early differences are most critical for the subsequent development of long term immunologic memory. Understanding these early differences may explain why only natural infection with V. cholerae gives rise to long term memory B cell responses which are important for protection against cholera. Because V. cholerae is a human-restricted pathogen, clinical studies are essential to address this question. We propose to draw upon existing collaborations between the Massachusetts General Hospital/Harvard Medical School (MGH/HMS), the International Centre for Diarrhoeal Disease Research, Bangladesh (ICDDR,B), the Emory Vaccine Center, and the Broad Institute of MIT/Harvard University to address this question in humans. Specifically, we will compare the activation of innate immune responses in mucosal tissue after cholera infection versus vaccination, and we will evaluate which of these differences correlate with long term memory B cell responses in cholera patients. We will also compare antibody secreting cell (ASC) responses in patients and vaccinees. Cloning of immunoglobulin genes and the production of these cloned antibodies from individual ASCs may improve our understanding of differences in the B cell responses between cholera patients and vaccine recipients, and the resulting antibodies may also provide tools with diagnostic and therapeutic potential. These studies will improve our understanding of the mechanisms through which innate immune responses at the mucosal surface foster long-lasting immunity and may point to novel strategies for improving upon current cholera vaccines.