Elucidating the Bacterial and Host Mechanisms Governing B. burgdorferi-Related Type I Interferon Responses

阐明控制伯氏疏螺旋体相关 I 型干扰素反应的细菌和宿主机制

• 批准号: 10302429
• 负责人: Jenny A. Hyde
• 金额: $ 22.34万
• 依托单位: TEXAS A&M UNIVERSITY HEALTH SCIENCE CTR
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-09-15 至 2023-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10302429
• 关键词: Adherence; Arthritis; Attenuated; Borrelia; Borrelia burgdorferi; Carditis; Cells; Characteristics; Clinical; Complement; DNA; Detection; Development; Disease; Endothelial Cells; Etiology; Evaluation; Fibroblasts; Genes; Genetic; Goals; Human; Immune response; Immunity; Immunologic Receptors; Immunoprecipitation; Immunotherapeutic agent; In Vitro; Individual; Infection; Inflammation; Inflammatory; Inflammatory Response; Innate Immune Response; Interferon Type I; Interferons; Invaded; Kinetics; Knockout Mice; Knowledge; Link; Lyme Arthritis; Lyme Disease; Mammalian Cell; Microscopy; Mouse Strains; Mus; Natural Immunity; Neurologic; Nucleic Acids; Open Reading Frames; Order Spirochaetales; Pathogenesis; Pathogenicity; Pathology; Pathway interactions; Patients; Pattern recognition receptor; Phase; Phenotype; Plasmids; Play; Production; Public Health; Publishing; Reporter; Reporting; Research; Resolution; Role; Severities; Shapes; Signal Transduction; Skin; Source; Stimulator of Interferon Genes; Testing; Tick-Borne Infections; Time; Tissues; Work; deep sequencing; extracellular; imaging system; immune clearance; immunopathology; in vivo; in vivo imaging; in vivo imaging system; innate immune pathways; innovation; joint inflammation; knock-down; macrophage; mutant; novel; pathogen; persistent symptom; response; sensor; spatiotemporal; uptake; vector-borne

PROJECT SUMMARY B. burgdorferi (Bb), the vector-borne etiologic agent of Lyme disease, elicits robust inflammatory responses while evading and modulating host immunity to establish a multi-systemic infection. Bb isolates that differ in the presence or sequence of the 36kb linear plasmid (lp36) possess varied ability to disseminate and cause Lyme-related pathology, which has been linked to differential induction of host inflammatory and type I interferon (IFN-I) responses. Multiple innate immune receptors have been proposed to trigger IFN-I during infection; however, the exact host pathways governing Bb-dependent IFN-I production, the kinetics of IFN-I responses in infected tissues, and the Bb factors modulating IFN-I induction remain unknown. Ongoing studies have identified a novel role for the intracellular cGAS-STING DNA sensing pathway in controlling IFN-I induction during Bb infection. This proposal will therefore test the hypothesis that cGAS-STING and B. burgdorferi lp36 genes control the IFN-I response to shape infection kinetics and Lyme-related immunopathology. Aim 1 will employ a variety of human and mouse knockout and knockdown cells to characterize cGAS- and STING-dependent IFN-I production over the course of Bb infection. Next, high resolution microscopy and a cGAS immunoprecipitation-deep sequencing approach will be utilized to define the intracellular niches where cGAS senses Bb and to identify the bacterial and/or host DNA species that activate cGAS. To define roles in vivo, wildtype, cGAS-, and STING-deficient mice will be infected with bioluminescent Bb for spatiotemporal evaluation of borrelial load by an In Vivo Imaging System (IVIS). Finally, Aim 1 will employ a novel, IFN-I GFP reporter mouse strain to characterize the in vivo kinetics and cellular sources of interferon over a 35 day time course. Aim 2 will elucidate the role of Bb 36kb linear plasmid (lp36) and genes encoded in the bbk35-bbk50 region of lp36 in host IFN-I induction. Bb lacking lp36 entirely or the bbk35-bbk50 region, as well as Bb lacking subregions of bbk35-bbk50, will be assessed for their ability to adhere, be taken up, and/or trigger IFN-I by primary murine and human macrophages and fibroblasts. Furthermore, in vivo imaging by IVIS will be used to determine the dissemination phenotypes of all lp36 mutants and associated complement strains. The ability of mutant strains to induce Lyme-related immunopathology in mice will be examined over time. This work is innovative as it will be the first to define how Bb, a predominately extracellular pathogen, induces IFN-I through the intracellular cGAS-STING pathway. Moreover, it will characterize novel roles for candidate borrelial genes in triggering IFN-I during early and late phases of infection and will examine their contribution to Lyme disease pathogenesis. In the long term, this research has the potential to reveal new immunotherapeutic avenues that may be effective against active infection or persistent symptoms of B. burgdorferi, such as Lyme arthritis.

项目摘要 B。莱姆病的媒介传播病原体--伯氏螺旋体（Bb）， 免疫应答，同时逃避和调节宿主免疫以建立多系统感染。Bb分离出 在36 kb线性质粒（lp 36）的存在或序列上不同，具有不同的传播能力， 导致莱姆病相关的病理，这已被链接到宿主炎症和I型的差异诱导 干扰素（IFN-I）应答。已经提出多种先天免疫受体在免疫过程中触发IFN-I。 感染;然而，控制BB依赖性IFN-I产生的确切宿主途径，IFN-I的动力学， 感染组织中的免疫应答，以及调节IFN-1诱导的Bb因子仍然未知。 正在进行的研究已经确定了细胞内cGAS-STING DNA传感途径在肿瘤细胞中的新作用。 在Bb感染期间控制IFN-I诱导。因此，本提案将检验cGAS-STING 和B。lp 36基因控制IFN-I对形状感染动力学和莱姆相关的应答 免疫病理学Aim 1将采用多种人类和小鼠敲除和敲低细胞， 表征在Bb感染过程中cGAS和STING依赖性IFN-I的产生。其次，高分辨率 显微镜和cGAS免疫沉淀-深度测序方法将用于确定细胞内 cGAS感测Bb的小生境，并鉴定激活cGAS的细菌和/或宿主DNA种类。到 定义体内作用，野生型、cGAS和STING缺陷小鼠将感染生物发光Bb， 通过体内成像系统（IVIS）对疏螺旋体载量进行时空评价。最后，目标1将采用 新的，IFN-I GFP报告小鼠品系，以表征干扰素的体内动力学和细胞来源， 35天的课程。目的2阐明Bb 36 kb线性质粒（lp 36）及其编码基因在Bb基因表达中的作用。 lp 36的bbk 35-bbk 50区域在宿主IFN-1诱导中的作用。完全缺乏lp 36或bbk 35-bbk 50区域的Bb，以及 由于Bb缺乏bbk 35-bbk 50的亚区域，将评估其粘附、被吸收和/或触发的能力 IFN-I通过原代鼠和人巨噬细胞和成纤维细胞。此外，通过IVIS的体内成像将是 用于确定所有Lp 36突变体和相关补体菌株的播散表型。的 将随时间检查突变株在小鼠中诱导莱姆病相关免疫病理学的能力。 这项工作是创新的，因为它将是第一个定义Bb，一种主要的胞外病原体， 通过细胞内cGAS-STING途径诱导IFN-I。此外，它将描述新的角色， 候选疏螺旋体基因在感染的早期和晚期触发IFN-I，并将检查其 莱姆病的发病机制。从长远来看，这项研究有可能揭示新的 可能有效对抗B的活动性感染或持续症状的免疫途径。 burgdorferi，如莱姆关节炎。