Bacillus anthracis - Host Interactions

炭疽病是由入侵细菌芽孢杆菌之间一系列复杂的相互作用引起的 炭疽菌和哺乳动物宿主。对于吸入性炭疽病，感染始于孢子进入 阿龙。肺泡巨噬细胞吞噬孢子，并将其运输到鸡的淋巴结节。 纵膈。最终，细菌的代谢活性形式传播到血液和其他 体内组织，达到每毫升10S CFU的浓度，并分泌炭疽毒素蛋白。在……里面 近年来，毒素蛋白的结构和功能成为研究的重点。然而，炭疽病 疾病，无论是自然获得的还是故意传播孢子的结果，都是由 感染炭疽杆菌，而不是简单地获得毒素。尽管人类感染B。 炭疽病，几乎完全缺乏基本的细胞和分子机制的知识。 细菌通过它与宿主相互作用。这里提出的研究结果将填补这一关键空白 了解并揭示细菌和宿主目标，以产生新的炭疽治疗药物。 我们将使用体外巨噬细胞模型和体内小鼠模型来鉴定病原体和宿主 目标对感染的多个早期步骤很重要。病原菌和寄主因素在发病过程中的重要性 在这两个模型中，将通过调节候选炭疽杆菌和 巨噬细胞靶点。在目标1中，我们将鉴定和表征炭疽芽孢杆菌和巨噬细胞 分子靶点对早期感染的多个步骤很重要。我们将建立一个详细的B。 炭疽-巨噬细胞相互作用。这项工作的主要部分将是表征两者的调制 炭疽杆菌-巨噬细胞相互作用引起的细菌和巨噬细胞基因表达 转录图谱和蛋白质组分析。在目标2中，我们将研究炭疽杆菌在 小鼠鼻腔安装炭疽模型，重点观察肺部反应。我们将检测炭疽杆菌 突变对模型中致病作用的减弱作用。炭疽杆菌的萌发、存活和持久力 肺脏将与肺组织病理学和免疫反应相关。我们将跟踪B的发展。 利用基于化学发光的活体成像技术对整个动物体内的炭疽进行成像。使用这些 通过分析，我们将建立一个完全毒力的炭疽杆菌菌株的空间和时间发展和 编码治疗候选基因的同源突变体被删除。 我们的长期目标是开发新的疗法来阻断炭疽杆菌孢子与 肺泡巨噬细胞。最有效的策略可能会采用一系列靶向抑制剂。 在感染过程中有多个步骤。细菌和巨噬细胞靶标实验显示 炭疽杆菌-巨噬细胞的相互作用将立即转发到RCE核心设施 重组表达和结晶，用于高分辨率结构分析。结构数据将是 用于基于结构的铅抑制剂模板的鉴定。

Anthrax disease results from a complex series of interactions between the invading bacterium, Bacillus anthracis, and the mammalian host. For inhalation anthrax, infection begins with entry of spores into the lung. Alveolar macrophages phagocytose the spores and transport them to lymph nodes of the mediastinum. Ultimately the metabolically active form of the bacterium disseminates to the blood and other body tissues, reaching concentrations up to 10s CFU per ml and secreting the anthrax toxin proteins. In recent years, research emphases have focused on toxin protein structure and function. However, anthrax disease, whether acquired naturally or as the result of intentional dissemination of spores, results from infection with B. anthracis, not simply acquisition of toxin. Despite the importance of human infection with B. anthracis, there is an almost complete lack of knowledge of fundamental cellular and molecular mechanisms by which the bacterium interacts with its host. Results of studies proposed here will fill this critical gap in knowledge and reveal bacterial and host targets for generation of new therapeutics for anthrax. We will use an in vitro macrophage model and in vivo murine model to identify pathogen and host targets important for multiple early steps in infection. The importance of pathogen and host factors during early infection will be assessed in both models by modulating expression of candidate B. anthracis and macrophage targets. In Aim 1 we will identify and characterize Bacillus anthracis and macrophage molecular targets important for multiple steps of early infection. We will establish a detailed model of B. anthracis-macrophage interactions. A major part of this work will be to characterize the modulation of both bacterial and macrophage gene expression as a result of B. anthracis-macrophage interactions, using transcriptional profiling and proteome analyses. In Aim 2 we will investigate B. anthracis development in a mouse nasal installation model for anthrax, focusing on the pulmonary response. We will test B. anthracis mutants for attenuation of pathogenesis in the model. B. anthracis germination, survival, and persistence in the lung will be correlated with lung histopathology and immune response. We will track development of B. anthracis in the whole animal using chemoluminescence-based in vivo imaging technology. Using these assays, we will establish the spatial and temporal development of a fully virulent B. anthracis strain and isogenic mutants deleted for genes encoding therapeutic candidates. Our long-term objective is to generate new therapeutics to block interactions of B. anthracis spores with alveolar macrophages. The most powerful strategy will probably employ a cocktail of inhibitors targeting multiple steps in the infectious process. Bacterial and macrophage targets shown experimentally to be important for B. anthracis-macrophage interactions will be immediately forwarded to RCE core-facilities to be expressed recombinantly and crystallized for high-resolution structural analysis. The structural data will be used for structural-based identification of lead-inhibitor templates.