Bacterial polyphosphates in sepsis

败血症中的细菌多磷酸盐

基本信息

批准号：
10573217
负责人：
Markus Bosmann
金额：
$ 53.71万
依托单位：
BOSTON UNIVERSITY MEDICAL CAMPUS
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：
2021-02-22 至 2025-01-31
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10573217
关键词：
Address Affinity Chromatography Agonist Alpha Granule Bacteremia Bacteria Bacterial Infections Binding Proteins Biological Blood Platelets Blood coagulation Bradykinin Cells Cellular Indexing of Transcriptomes and Epitopes by Sequencing Chemicals Coagulation Process Colon Complement Activation Data Environment Escherichia coli Event FDA approved Future Glycolysis Gnotobiotic Growth Heterogeneity Host Defense Human Immune Immune response Immunity Incubated Infection Inflammation Integration Host Factors Intervention Intestinal Mucosa Invaded Knowledge Label Length Light Link Macrophage Mammalian Cell Measures Mediating Metabolic Metabolism Modeling Molecular Molecular Chaperones Mononuclear Morbidity - disease rate Mucous Membrane Mus Natural Immunity Nutrient Organism Orthophosphate Outcome Pathogenesis Patients Peritoneal Peritoneal Sepsis Phagocytes Pharmaceutical Preparations Phenotype Polymers Polyphosphate kinase Polyphosphates Prevention Production Proteins Proteomics Reaction Recombinants Reporting Research Research Project Grants Role Saccharomyces cerevisiae Sampling Sepsis Severities Shapes Signal Pathway Signal Transduction Source Sterility Stress Surrogate Endpoint TLR4 gene Testing Therapeutic Titrations Work arginase bacterial metabolism cecal ligation puncture chemokine cytokine fighting host-microbe interactions improved inflammatory milieu inorganic phosphate insight mast cell monocyte mortality mutant neutrophil novel pathogen polymicrobial sepsis proteogenomics recruit response response to injury transcriptome

项目摘要

Project Summary: Sepsis remains a leading cause of morbidity and mortality with almost 50 million cases per year worldwide. In the absence of FDA-approved drugs, there is a high demand for better insights into the host- microbe interactions that define the molecular pathogenesis of sepsis. Polyphosphates are linear polymers of inorganic phosphate (Pi) residues that are present in all living organisms. The metabolism of bacteria accumulates long-chains of polyphosphates (Pi: n≥1,000) in contrast to the short-chain polyphosphates (Pi: n<100) typically found in mammalian cells. The biologic effects are dependent on chain length. Emerging data suggest that short-chain polyphosphates modulate blood coagulation and inflammation, while the role of long- chain, bacteria-derived, polyphosphates in sepsis is an understudied research field. Our preliminary work suggests that neutralization of polyphosphates or bacterial polyphosphate deficiency improves survival of peritoneal sepsis induced by cecum ligation and puncture (CLP) in mice. In sterile macrophage cultures, long- chain polyphosphates modulate LPS/TLR4-induced macrophage polarization, iNOS expression and immuno- metabolism. Here, we propose to test the central hypothesis that bacterial polyphosphates are lethal metabolites in sepsis because of their detrimental interference with the innate host response to infection. To shed light into the biological activities of polyphosphates, we propose to address 3 specific aims: (1) To study the effects of polyphosphate neutralization, we will use a recombinant exopolyphosphatase (PPX) protein and characterize its activities on the host response to polymicrobial CLP sepsis. A single-cell proteogenomics approach (CITE-Seq) will aim to capture the heterogeneity/polarization of invading professional phagocytes as a function of polyphosphates. The polyphosphates will be measured in sepsis samples of mice and humans. (2) To characterize the direct interference of polyphosphates with the functions of cultured macrophages, we will combine bacterial TLR agonists with synthetic polyphosphates of different chain length. It will be studied if polyphosphates curb STAT/IRF signaling pathways for modulating iNOS, L-arginase, cytokines/chemokines, and metabolic reprogramming (OXPHOS, glycolysis). In addition, affinity purification combined with label-free proteomics will aim for the identification of novel polyphosphate targeted proteins in macrophages; to better understand the mechanisms how polyphosphates interfere with phagocyte responses in sepsis. (3) In gnotobiotic mice, monocolonized with a polyphosphate-deficient E. coli mutant (Δppk), we will investigate how bacteria- derived polyphosphates shape innate immunity before and after monomicrobial CLP sepsis. Peritoneal and intestinal mucosal macrophages will be characterized and compared for their functions, transcriptome plasticity and immuno-metabolic phenotypes. This research project will provide novel insights into the unexplored activities of bacterial polyphosphates within the networks of host-pathogen interactions of sepsis and may ultimately advance strategies for therapeutic reversal of maladaptive inflammatory milieus.

项目摘要：脓毒症仍然是发病和死亡的主要原因，每年有近 5000 万例脓毒症在全球范围内缺乏 FDA 批准的药物的情况下，迫切需要更好地了解宿主 - 定义败血症分子发病机制的微生物相互作用聚磷酸盐是线性聚合物。存在于所有生物体中的无机磷酸盐 (Pi) 残留物细菌的新陈代谢。与短链聚磷酸盐 (Pi: n≥1,000) 相比，积累长链聚磷酸盐 (Pi: n≥1,000) n<100）通常存在于哺乳动物细胞中，其生物学效应取决于新出现的数据。表明短链聚磷酸盐调节血液凝固和炎症，而长链聚磷酸盐的作用脓毒症中的细菌源性多磷酸盐是我们的初步研究领域。表明多磷酸盐的中和或细菌多磷酸盐缺乏可提高细菌的存活率在无菌巨噬细胞培养物中，通过盲肠结扎和穿刺（CLP）诱导的腹膜败血症。链多磷酸调节 LPS/TLR4 诱导的巨噬细胞极化、iNOS 表达和免疫在这里，我们建议检验细菌多磷酸盐是致命代谢物的中心假设。在败血症中，因为它们会干扰宿主对感染的先天反应。为了研究多磷酸盐的生物活性，我们建议解决 3 个具体目标：（1）研究多磷酸中和，我们将使用重组外多磷酸酶（PPX）蛋白并表征其单细胞蛋白质组学方法（CITE-Seq）对宿主对多种微生物 CLP 脓毒症反应的影响。将旨在捕获入侵专业吞噬细胞的异质性/极化作为函数多磷酸盐将在小鼠和人类的败血症样本中进行测量 (2) To。表征多磷酸盐对培养巨噬细胞功能的直接干扰，我们将将细菌 TLR 激动剂与不同链长的合成聚磷酸盐结合起来将被研究。多磷酸盐抑制 STAT/IRF 信号通路，调节 iNOS、L-精氨酸酶、细胞因子/趋化因子、和代谢重编程（OXPHOS、糖酵解）此外，亲和纯化与无标记相结合。蛋白质组学的目标是更好地鉴定巨噬细胞中的新型多磷酸靶向蛋白质； (3) 在知生中小鼠，单克隆有缺乏多磷酸盐的大肠杆菌突变体（Δppk），我们将研究细菌如何- 衍生的多磷酸盐在单微生物 CLP 脓毒症前后形成先天免疫。将表征并比较肠粘膜巨噬细胞的功能、转录组可塑性该研究项目将为未探索的活动提供新的见解。脓毒症宿主-病原体相互作用网络中细菌多磷酸盐的变化，最终可能逆转适应不良的炎症环境的治疗进展的策略。