Global Gene Expression Responses of Francisella tularensis to intracellular Infection of Human Alveolar Macrophages

土拉弗朗西斯菌对人肺泡巨噬细胞细胞内感染的整体基因表达反应

基本信息

批准号：
10377914
负责人：
Shawn J. Skerrett
金额：
$ 22.36万
依托单位：
UNIVERSITY OF WASHINGTON
依托单位国家：
美国
项目类别：
财政年份：
2021
资助国家：
美国
起止时间：
2021-03-25 至 2025-02-28
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10377914
关键词：
Address Aerosols Alveolar Macrophages Attenuated Bacteria Bacterial Genes Bacterial Infections Behavior Biochemical Pathway Cell Line Cells Complex Data Development Disease Environment Exhibits Francisella Francisella tularensis Gene Expression Gene Expression Profiling Genes Goals Growth Host Defense Human Immune Immune response In Vitro Infection Infiltration Inflammation Inflammatory Inflammatory Response Inhalation Innate Immune Response Kinetics Linear Regressions Link Location Lung Lung infections Maps Measures Metabolic Metabolic Pathway Modeling Mus Organism Outcome Pathogenesis Pathway interactions Phagosomes Phase Phenotype Play Pneumonia Prevention approach Production Proteins Pulmonary tularemia Research Structure of parenchyma of lung System Testing Therapeutic Intervention Time Tularemia Update Vaccines Virulence Virulent Work adaptive immunity antimicrobial bioweapon chemokine cytokine data integration defense response first responder genome annotation genome-wide in vivo insight mutant novel novel strategies novel therapeutic intervention parasitism pathogen pathogenic bacteria reconstruction response transcriptome vaccine development

项目摘要

Francisella tularensis, the cause of tularemia, is a highly virulent intracellular pathogen and a Tier 1 select agent with the potential to cause severe disease as an airborne bioweapon. The virulence of F. tularensis is linked to its capacity to evade recognition by the host, suppress immune responses, and replicate inside of host cells. Because specialized facilities are required for work with fully virulent F. tularensis, much of the research in this field has been done with closely related but less virulent strains of Francisella, including Francisella novicida, which is highly virulent for mice but not for humans. Pneumonia is the most lethal form of tularemia, and the target cell of Francisella in the lungs is the alveolar macrophage. The interaction of F. tularensis with human AM has not been studied. The overall goal of this project is to identify key mechanisms underlying the parasitism of human AM, using an approach that compares the interactions of human AM with fully virulent and attenuated strains of Francisella. Specific Aim 1: Profile F. tularensis global gene expression responses within primary human alveolar macrophages (AM) at distinct phases of bacterial intracellular location. Identify changes in Francisella gene expression in i) bacterial cultures and ii) primary human AMs at time-points corresponding to distinct phases of the bacterial intracellular cycle (phagosomal/cytosolic/replicative). AMs will be infected with either highly virulent F. tularensis subsp. tularensis (Ft), a deletion mutant of Ft lacking type VI secretion, or attenuated F.tularensis subsp novicida (Fn) to identify bacterial responses to the host environment that are unique to virulent infection. Specific Aim 2: Identify F. tularensis gene responses that target host immune pathways through correlation with defensive protein production. Innate immune responses in AMs infected with either Ft or Fn will be assessed by measuring cytokine and chemokine. Multiple statistical data integration approaches will be used to model the relationship between host inflammation with bacterial gene responses and bacterial growth kinetics measured in Aim 1. This will identify bacterial responses unique to virulent Ft and that correlate with suppression of AM innate immune responses at distinct stages of the bacteria's intracellular lifecycle. Specific Aim 3: Model F. tularensis metabolic gene expression changes within primary human AM. Use a metabolic network reconstruction of F. tularensis subsp. holarctica vaccine strain (LVS) to include genome annotations from Ft and Fn and use this model to compute pathway usage across the metabolic network. Gene expression data generated in Aim 1 will be mapped against this updated model to explore shifts in pathway usage in highly virulent and attenuated Francisella strains at distinct stages of the intracellular lifecycle. These studies will yield novel insights into the interaction of F. tularensis with human AM that will guide subsequent work directed at further understanding of the mechanisms underlying the pathogenesis of pneumonic tularemia, informing the development of novel strategies for therapeutic intervention.

francisella tuarlarensis是t骨的原因，是一种高毒的细胞内病原体，一级1选择有可能引起严重疾病作为空中生物武器的代理。 F. tularensis的毒力是与其逃避宿主认可的能力有关，抑制免疫反应并在内部复制宿主细胞。由于使用充分毒化的F. tularensis需要专门的设施，因此该领域的研究已经与弗朗西斯拉的密切相关但毒气较少的菌株进行，包括 Francisella Novicida，对小鼠具有很高的毒力，但对人类没有。肺炎是最致命的形式肺部的tularemia和Francisella的靶细胞是肺泡巨噬细胞。 F的相互作用。尚未研究与人类AM的Tularensis。该项目的总体目标是确定关键机制使用一种方法来比较人类与人类相互作用的方法弗朗西斯菌的全毒和减毒菌株。特定目标1：特征F. tularensis全局基因表达反应巨噬细胞（AM）在细菌细胞内位置的不同阶段。识别Francisella基因的变化在i）细菌培养物和ii）在与对应于不同阶段的时间点上的原代人AM 细菌细胞内循环（吞噬/胞质/复制）。 AM将被高度毒气感染 F. tularensis subsp。 Tularensis（ft），缺乏VI型的缺失突变体，或衰减的f.tularensis 亚种novicida（FN）确定对宿主环境的细菌反应，这是有毒感染所独有的。特定目的2：确定靶向宿主免疫途径的F. tularensis基因反应与防御蛋白产生的相关性。被FT或FN感染的AMS中的先天免疫反应将通过测量细胞因子和趋化因子来评估。多种统计数据集成方法将是用于建模与细菌基因反应与细菌生长之间的宿主炎症之间的关系在AIM 1中测量的动力学。这将识别有毒Ft独有的细菌反应，并且与在细菌的细胞内生命周期的不同阶段抑制AM先天免疫反应。特定目的3：F。tularensis代谢基因表达在原代人中的变化。使用 F. tularensis subsp的代谢网络重建。 Holarctica疫苗菌株（LVS），包括基因组 FT和FN的注释，并使用此模型来计算整个代谢网络的途径使用情况。基因 AIM 1中生成的表达数据将针对此更新的模型映射，以探索路径中的变化在细胞内生命周期的不同阶段，在高毒和减弱的弗朗西斯菌菌株中使用使用。这些研究将产生有关F. tularensis与人类AM相互作用的新见解，这将指导随后的工作是针对进一步理解发病机理的机制的进一步理解肺炎tularemia，为治疗干预的新策略提供了发展。