B. burgdorferi Hematogenous Dissemination

伯氏疏螺旋体的血行传播

• 批准号: 6913633
• 负责人: Ira S. Schwartz
• 金额: $ 35.1万
• 依托单位: NEW YORK MEDICAL COLLEGE
• 依托单位国家: 美国
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-07-15 至 2009-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6913633
• 关键词: Borrelia; Lyme disease; clinical research; gene expression; genotype; host organism interaction; human tissue; laboratory mouse; molecular pathology; northern blottings; pathologic process; polymerase chain reaction; protein sequence; proteomics; tissue /cell culture; virulence

DESCRIPTION (provided by applicant): Lyme disease, the most prevalent arthropod-borne disease in the United States, is caused by infection with the spirochete, Borrelia burgdorferi. Despite intensive study in recent years little is known regarding the pathogenesis of infection at the molecular level. We have determined the genetic diversity among clinical isolates of B. burgdorferi and shown that spirochete dissemination varies significantly in patients and mice infected with distinct genotypes. These results demonstrate that different genotypes of B. burgdorferi possess varying potential for dissemination in an infected host. We hypothesize that these differences are the result of variations in gene content and/or expression among different genotypes. We propose to employ functional genomics and proteomics to gain insight into possible differences in gene/protein expression between B. burgdorferi strains with differing capacities for hematogenous dissemination. The long-term objective of this project is elucidation of genes and/or proteins that mediate B. burgdorferi virulence. The following specific aims are proposed: 1) global gene expression of B. burgdorferi clinical isolates of differing genotype in varying environments will be monitored by gene array; 2) differences in protein expression among the various genotypes will be assessed by proteomics; 3) the roles of candidate virulence genes in pathogenesis of Lyme disease will be evaluated by monitoring expression for a number of the most promising candidate genes will be monitored in early Lyme disease patients and infected mice by real-time RT-PCR; 4) selected candidate virulence genes will then be targeted for insertional inactivation and complementation. The effects of such genetic manipulation should provide direct demonstration of the critical role such genes may play in spirochete pathogenesis. \The combination of functional genomics, in vivo and genetic approaches proposed here should provide for the comprehensive assessment of the molecular basis of pathogenesis for B. burgdorferi isolates with varying potential for bloodstream dissemination and result in identification of determinants required for spirochete dissemination. This will provide new insights into the natural history of B. burgdorferi infection in humans, which, in turn, may have implications for prevention, treatment, and diagnosis of Lyme disease.

描述（由申请人提供）：莱姆病是美国最流行的节肢动物传播疾病，由螺旋体伯氏疏螺旋体感染引起。尽管近年来进行了深入的研究，但在分子水平上对感染的发病机制知之甚少。我们确定了B临床分离株的遗传多样性。Burgdorferi的研究表明，在感染不同基因型的患者和小鼠中，螺旋体的传播有显著差异。这些结果表明，不同基因型的B。伯氏螺旋体在受感染的宿主中具有不同的传播潜力。我们假设这些差异是不同基因型之间基因含量和/或表达变化的结果。我们建议采用功能基因组学和蛋白质组学来深入了解B之间基因/蛋白质表达的可能差异。具有不同的血行播散能力的伯氏菌株。该项目的长期目标是阐明介导B的基因和/或蛋白质。伯氏菌毒力提出了以下具体目标：1）B的全局基因表达。通过基因阵列监测不同环境中不同基因型的伯氏临床分离株; 2）通过蛋白质组学评估不同基因型之间蛋白质表达的差异; 3）候选毒力基因在莱姆病发病机制中的作用将通过监测许多最有希望的候选基因的表达来评估，这些候选基因将在早期莱姆病患者和感染小鼠中通过真实的-时间RT-PCR; 4）然后将选定的候选毒力基因靶向用于插入失活和互补。这种遗传操作的影响应该提供直接的证据，这些基因可能在螺旋体发病机制中发挥关键作用。 本文提出的功能基因组学、体内和遗传学方法相结合，将为全面评价B发病机制的分子基础提供依据。具有不同的血流传播潜力的伯氏螺旋体分离物，并鉴定螺旋体传播所需的决定因素。这将为B的自然历史提供新的见解。这反过来可能对莱姆病的预防、治疗和诊断有意义。