Molecular and Metabolic inter-kingdom actions of a bacterial quorum sensing signal in promotion of host tolerance/resilience.

细菌群体感应信号在促进宿主耐受性/弹性方面的分子和代谢界间作用。

• 批准号: 10080028
• 负责人: LAURENCE G RAHME
• 金额: $ 67.1万
• 依托单位: MASSACHUSETTS GENERAL HOSPITAL
• 依托单位国家: 美国
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-01-01 至 2022-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10080028
• 关键词: 3-Dimensional; ATP Synthesis Pathway; Acetyl Coenzyme A; Acetylation; Adoptive Transfer; Anabolism; Animal Model; Antibiotics; Autophagocytosis; Bacteria; Bacterial Infections; Bacterial Model; Behavior; Biological; Bone Marrow Cells; Cells; ChIP-seq; Characteristics; Chemistry; Chromatin; Chronic; Citric Acid Cycle; Clinical; Communication; ESKAPE pathogens; Energy Metabolism; Epigenetic Process; Genome; Goals; HDAC1 gene; Health; Histone Acetylation; Histone Deacetylase; Histone H3; Human; Immune; Immune response; Immune system; Immunologic Memory; In Vitro; In Vivo NMR Spectroscopy; Infection; Inflammation; Inflammatory; Inflammatory Response; Knowledge; Ligase; Lysine; Maintenance; Mediating; Mediator of activation protein; Memory; Metabolic; Metabolism; Microbe; Microbial Biofilms; Modeling; Molecular; Mus; Oligonucleotides; Pathogenicity; Patients; Pharmaceutical Preparations; Pharmacology; Prokaryotic Cells; Promoter Regions; Pseudomonas aeruginosa; Publications; Regulation; Relapse; Resistance; Role; Series; Signal Transduction; Signaling Molecule; System; TNF gene; Testing; Time; Tissues; Training; Variant; Visualization; Work; antibiotic tolerance; chronic infection; clinically relevant; cytokine; effective therapy; epigenetic memory; epigenetic regulation; epigenome; experimental study; fatty acid biosynthesis; fitness; histone acetyltransferase; immunopathology; immunoregulation; improved; in vivo; inhibitor/antagonist; insight; knock-down; macrophage; metabolome; novel; pathogen; pathogenic bacteria; persistent bacterial infection; promoter; quorum sensing; reconstitution; resilience; small molecule; therapeutic development; therapy development

Our long-term goal is to develop treatments that may improve resilience to pathogen damage in patients with serious infections, including chronic and relapsing bacterial infections, for which effective treatments are lacking. Bacterial quorum sensing (QS) signals are important mediators of immunomodulation. However, it remains unclear how microbes utilize immunomodulatory signals to maintain a long-term presence and thwart clearance and how hosts avoid harmful inflammatory response to a pathogen’s presence. In our previous work, we identified a small volatile QS molecule excreted by Pseudomonas aeruginosa (PA), 2-aminoacetophenone (2-AA), that acts as an inter-kingdom “infochemical” to alter immune responses and metabolism in a manner that trains the host to increase host tolerance/resilience (HT/R), which is defined as the host's ability to cope with bacterial encounter without a consequent reduction in fitness; these alterations allow the pathogen to avoid elimination and persist in mammalian tissues. The specific goal of this application is to decipher paradigmatically the mode of action of a bacterial product on host metabolome and epigenome in order to gain insights into the first mechanistic example of a QS molecule that reprograms the host metabolome and epigenome to promote HT/R. Our hypothesis is that the long-lasting immunomodulatory changes exerted by 2-AA through the sustained activity of histone deacetylase 1 (HDAC1) derive from 2-AA–promoted metabolic alterations; and that the interplay between host metabolome and epigenome contribute to the mutual bacterial-host fitness that defines HT/R. We propose to achieve our goal through experiments employing PA, a recalcitrant Gram-negative ESKAPE bacterium that defies eradication by antibiotics, forms biofilms, and exemplifies current clinically problematic pathogens. In Aim 1, we will examine how 2-AA maintains epigenetic reprogramming by assessing the molecular mechanisms of long-term immunomodulation in immune memory in vivo promoted by 2-AA tolerization, and determine the occurring metabolic changes by performing functional studies. In Aim 2, we will interogate the capacity of 2-AA to regulate macrophage autophagy in tissues and conduct a meticulous analysis of the key host players and cellular mechanisms that permit bacterial persistence. In Aim 3, using murine in vitro and in vivo systems in addition to human primary macrophages, we will evaluate the interplay between 2-AA promoted epigenetic control and metabolic alterations by undertaking molecular and functional approaches. The impact of these alterations in bacterial persitence, histone acetylation, energy metabolism and the efficacy of our novel anti-2AA compound will be asssessed using clinically relevant animal models of infection. In Aim 4, we will seek to identify 2-AA’s direct target using click chemistry. The proposed elucidation of “host tolerance training” mechanisms is intended to improve our understanding of HT/R that remains extremely limited. In this context, the findings may offer opportunities for being applied to the development of therapeutic treatments that can train the host to augment resilience to infection. In principle, the knowledge to be obtained could be applicable to persistent infections triggered also by other bacteria because QS is broadly conserved among Gram-negative and Gram-positive human bacterial pathogens and, as such, 2-AA-like molecules are likely to exist in other bacteria.

我们的长期目标是开发可提高严重感染患者（包括慢性和复发细菌感染）患者病原体损害的韧性的治疗方法，为此缺乏有效的治疗。细菌群体灵敏度（QS）信号是免疫调节的重要介体。但是，尚不清楚微生物如何利用免疫调节信号来维持长期存在和阻碍清除，以及宿主如何避免对病原体存在的有害炎症反应。在以前的工作中，我们确定了铜绿假单胞菌（PA），2-氨基乙烯酮（2-AA）独家挥发性QS分子，该分子是一种“ kingdom”的“ InfoChemical”，以改变宿主的宿主（宿主）的宿主（HOST）的供应（HOST/RECELAINCE/RECELIENCE）（HT），以改变免疫反应和代谢，以改变免疫力和代谢。遇到细菌而不会降低健身；这些改变允许病原体避免消除并持续在哺乳动物组织中。该应用的具体目标是通过对宿主代谢组和表观基因组上细菌产物的作用方式解密，以便深入了解QS分子的第一个机械示例，该QS分子重新编程了宿主代谢组和表观基因组以促进HT/R。我们的假设是，2-AA通过组蛋白脱乙酰基酶1（HDAC1）的持续活性所施加的持久免疫调节变化源自2-AA促进的代谢改变；并且宿主代谢组和表观基因组之间的相互作用有助于定义HT/R的相互细菌宿主健身。我们建议通过使用PA（一种顽固的革兰氏阴性埃斯卡普细菌）实现目标，该实验定义了抗生素，形成生物膜并体现当前临床上有问题的病原体的放射线。在AIM 1中，我们将研究2-AA如何通过评估通过2-AA耐受性促进的体内免疫记忆中长期免疫调节的分子机制来保持表观遗传重编程，并通过执行功能研究来确定发生代谢的变化。在AIM 2中，我们将互助2-AA调节组织中巨噬细胞自噬的能力，并对关键宿主参与者和细胞机制进行细致的分析，以允许细菌持久性。在AIM 3中，除了人类原代巨噬细胞外，还将使用鼠在体外和体内系统中，我们将通过采用分子和功能方法来评估2-AA促进表观遗传控制和代谢改变之间的相互作用。这些改变在细菌中的影响，组蛋白乙酰化，能量代谢以及我们新型抗2AA化合物的效率将使用临床上相关的感染动物模型来评估。在AIM 4中，我们将寻求使用点击化学的直接目标确定2-AA的直接目标。提出的“宿主耐受训练”机制的阐明旨在提高我们对HT/R的理解，这仍然非常有限。在这种情况下，这些发现可能会为可以训练宿主培训以增强感染的弹性的治疗疗法的开发提供机会。原则上，获得的知识可能适用于其他细菌触发的持续感染，因为QS在革兰氏阴性和革兰氏阴性人类细菌病原体中广泛保守，因此，2-AA样分子可能存在于其他细菌中。