VIRULENCE ASSOCIATED PROTEINS OF BORRELIA BURGDORFERI

伯氏疏螺旋体毒力相关蛋白

• 批准号: 6170668
• 负责人: JON T SKARE
• 金额: $ 19.92万
• 依托单位: TEXAS A&M UNIVERSITY HEALTH SCIENCE CTR
• 依托单位国家: 美国
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-04-01 至 2003-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6170668
• 关键词: Borrelia; active immunization; bacterial antigens; gene expression; genetic mapping; laboratory mouse; membrane proteins; microorganism culture; nonblood lipoprotein; protein purification; protein sequence; recombinant proteins; serology /serodiagnosis; virulence

DESCRIPTION (Adapted from the Applicant's Abstract): Borrelia burgdorferi sensu lato, the etiologic agent of Lyme disease, causes a multi-system disorder that may progress into a persistent infection characterized by significant morbidity. The overall goal of this proposal is to identify and characterize virulent strain associated (VSA) outer membrane (OM) proteins, both those that are outer membrane- spanning (Oms) and lipoproteins, that function as protective immunogens. The investigators' long-term goal is to link protective immunity elicited by these proteins to pathogenic mechanisms. Specifically, this study proposes to: (1) Purify and characterize a 28 and 35 kilodalton (kDa) virulent strain associated (VSA) OM proteins of B. burgdorferi that are specific to infectious isolates. The native forms of the 28 and 35 kDa OM proteins will be purified from OM vesicles derived from B. burgdorferi and their amino terminal or internal peptide sequences determined. These sequences will then be used to identify the genes encoding these proteins by screening the B. burgdorferi genomic database; (2) Characterize four virulent strain associated (VSA) antigens of B. burgdorferi identified from a phage lambda expression library. We will determine the extent of differential expression of the VSA antigen in virulent versus avirulent B. burgdorferi and evaluate whether these antigens are either expressed in infected animals or temperature regulated; and (3) Test these OM VSA antigens identified for their ability to confer protective immunity. Recombinant VSA proteins will be overproduced, purified, and used to immunize mice. The native VSA OM 28 and 35 kDa proteins will be incorporated into liposomes and the resulting proteoliposomes used to immunize mice. Immunized animals will then be challenged with infectious B. burgdorferi. Serum specific for protective immunogens will be tested to determine whether these antibodies confer passive protection and whether antibodies mediate adherence inhibition or preferentially kill in vitro cultivated virulent B. burgdorferi in a complement dependent manner. Determination of the protective abilities of different B. burgdorferi antigens expressed in the host relative to those expressed during in vitro cultivation, will facilitate in the development of a vaccine cocktail to protect against non-clonal, environmental isolates of B. burgdorferi. Furthermore, these studies will provide insight into pathogenic mechanisms mediated by VSA antigens of B. burgdorferi.

描述(改编自申请者摘要)：疏螺旋体 莱姆病的病原体伯氏杆菌能引起一种 可能进展为持续性感染的多系统障碍 以严重的发病率为特点。这个项目的总体目标是 建议鉴定和鉴定相关的毒力菌株 (VSA)外膜(OM)蛋白，两者都是外膜- 跨膜蛋白(OMS)和脂蛋白，起到保护性免疫原的作用。 调查人员的长期目标是将保护性免疫 由这些蛋白引发的致病机制。具体地说，这 研究建议：(1)提纯和表征一个28千吨和35千吨的 伯氏杆菌(B.burgdorferi)毒力相关株(VSA)OM蛋白 是传染性分离株所特有的。28和28的原生形式 35 kDa的OM蛋白将从B. 伯氏杆菌及其氨基末端或内部肽序列 下定决心。然后这些序列将被用来识别基因 通过筛选伯氏杆菌基因组编码这些蛋白 数据库；(2)鉴定四株毒力相关株(VSA) 从噬菌体lambda表达中鉴定伯氏杆菌抗原 图书馆。我们将确定差异表达的程度 伯氏杆菌强毒株与无毒株VSA抗原的比较及评价 无论这些抗原是在受感染的动物体内表达还是 温度调节；以及(3)检测这些被鉴定为 它们赋予保护性免疫力的能力。重组VSA蛋白 将被大量生产，提纯，并用于免疫小鼠。原住民 VSA OM28和35 kDa蛋白将被整合到脂质体中并 由此产生的蛋白质脂质体用于免疫小鼠。免疫动物 然后会受到传染性伯氏杆菌的挑战。血清特异性 对保护性免疫原进行测试，以确定这些 抗体提供被动保护，以及抗体是否起中介作用 黏附抑制或优先杀死体外培养的毒力 B.burgdorferi以补体依赖的方式表达。确定了 表达的不同伯氏杆菌抗原的保护性 相对于在体外培养过程中表达的那些，宿主将 促进疫苗鸡尾酒的开发，以防止 伯氏杆菌的非克隆环境分离株。此外，这些 研究将深入了解VSA介导的致病机制 伯氏杆菌抗原。