Comprehensive Analysis of Borrelia burgdorferi Adhesins

描述（由申请人提供）：伯氏疏螺旋体是莱姆病的一种病原体，可引起持续性感染，影响关节、心脏、皮肤和神经系统。这种螺旋体在哺乳动物宿主中的各种位点传播和持续存在的能力表明，在感染期间，与哺乳动物细胞和细胞外基质的相互作用不断发生。事实上，许多文献记载或假定的粘附素已被确定，这表明多种粘附途径的协同作用使B。在其特征性的多相和多系统感染期间，伯氏菌能够进行连续的步骤。不幸的是，我们目前知识的一个重要差距是缺乏任何机械信息来告知这个有吸引力的模型。这种缺乏洞察力的部分原因是，迄今为止确定的一些粘附素显示出结合活性的重叠，这是一个混淆任何单一粘附途径的直接分析的因素。在这里，我们提出了一个全面的体外和体内分析的性质和功能的每个粘附素的情况下，潜在的冗余机制。为此，该应用程序汇集了三名主要调查员，每个人都有一个独特的专业领域，以解决这一关键的知识差距。这三个实验室将采用最先进的方法，包括产生功能增益B。在非粘附性、高传代菌株背景中的伯氏菌突变体和测试菌株的体外粘附活性（目的1，Leong实验室），与亲本菌株相比，小鼠组织中所有功能获得性突变体的细菌负荷定量（目标2，Coburn实验室），以及活体显微镜检查每种菌株与活小鼠中血管系统之间相互作用的性质（Aim 3，Chaconas实验室）。因此，该项目构成了对B的不同粘附素的作用的第一次系统检查。在免疫活性动物中建立播散性感染的能力。我们的长期目标是了解不同粘附素的生物化学活性如何共同发挥作用，使B。克服宿主障碍，建立持续性、播散性感染。随着莱姆病在北方半球的流行继续扩大，就病例数量和地理分布而言，这项工作可能会阐明B。伯氏菌在人类中引起莱姆病，并在其动物宿主中持续存在。这个创新的多PI项目汇集了具有独特专业知识的团队，可以对大量B进行全面调查。具有确定的生物化学活性的伯氏螺旋体蛋白。这些蛋白质可能是开发作为候选疫苗或作为治疗干预的靶向的优秀候选物。

DESCRIPTION (provided by applicant): Borrelia burgdorferi, a causative agent of Lyme disease, establishes persistent infection that can affect the joints, heart, skin, and nervous system. The abilities of this spirochete to disseminate and persist in a variety of sites in the mammalian host indicate that interactions with mammalian cells and extracellular matrix occur continually during infection. In fact, many documented or putative adhesins have been identified, suggesting that the concerted action of diverse adhesion pathways enables B. burgdorferi to negotiate successive steps during its characteristic multiphasic and multisystemic infection. Unfortunately, an important gap in our current knowledge is the lack of any mechanistic information to inform this attractive model. This paucity of insight is due in part to the fact that some of the adhesins identified to date display an overlap in binding activities, a factor that confounds straightforward analysis of any single adhesion pathway. Here we propose a comprehensive in vitro and in vivo analysis of the properties and function of each adhesin in the absence of potentially redundant mechanisms. To this end, this application brings together three principal investigators, each with a unique area of expertise, to address this critical knowledge gap. The three laboratories will employ state of the art approaches, including generation of gain-of-function B. burgdorferi mutants in a non-adherent, high-passage strain background and testing of the strains for in vitro adhesion activities (Aim 1, Leong lab), quantification of bacterial burdens for all gain-of-function mutants in comparison to the parental strain in mouse tissues (Aim 2, Coburn lab), and intravital microscopic examination of the nature of the interaction between each of the strains and the vasculature in living mice (Aim 3, Chaconas lab). This project therefore constitutes the first systematic examination of the roles of the diverse adhesins of B. burgdorferi in the ability of the organism to establish disseminated infection in immunocompetent animals. Our long-term goal is to understand how the biochemical activities of different adhesins function together to allow B. burgdorferi to overcome host barriers to the establishment of persistent, disseminated infection. As Lyme disease prevalence continues to expand in the Northern hemisphere, in terms of both case numbers and geographic distribution, this work may illuminate how B. burgdorferi causes Lyme disease in humans and persists in its animal reservoirs. This innovative multiple PI project brings together teams with unique expertise that will allow comprehensive investigations of a large set of B. burgdorferi proteins with defined biochemical activities. These proteins may be excellent candidates for development as vaccine candidates or for targeting as therapeutic interventions.