Synergistic killing of bacterial pathogens by histones

组蛋白协同杀死细菌病原体

• 批准号: 10664005
• 负责人: Albert Siryaporn
• 金额: $ 47.5万
• 依托单位: UNIVERSITY OF CALIFORNIA-IRVINE
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-07-12 至 2027-06-30
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10664005
• 关键词: Address; Antibiotic Resistance; Antibiotics; Attention; Bacteria; Bacterial Antibiotic Resistance; Bacterial Infections; Bacteriology; Biology; Biophysics; Cell Wall; Cells; Cellular biology; Cessation of life; Chemicals; Chronic; Communities; Cryoelectron Microscopy; DNA; Data; Development; Diabetes Mellitus; Diabetic mouse; Engineering; Fiber; Foundations; Gene Expression; Goals; Healthcare; Histone H2A; Histones; Human; Immobilization; Immune; Immunology; In Vitro; Infection; Infectious Skin Diseases; Interdisciplinary Study; Malignant Neoplasms; Measures; Membrane; Modeling; Modernization; Modification; Morbidity - disease rate; Multi-Drug Resistance; Mus; Outcome; Pathway interactions; Patients; Peptidoglycan; Proliferating; Pseudomonas aeruginosa; Reporting; Resistance; Shapes; Skin; Soft Tissue Infections; Standardization; Staphylococcus aureus; Surface; Testing; Therapeutic; Work; Wound Infection; antimicrobial; antimicrobial peptide; antimicrobial peptide LL-37; bactericide; cathelicidin; cathelicidin antimicrobial peptide; chronic wound; combat; design; diabetic; effective therapy; experimental study; extracellular; health care settings; histone modification; human pathogen; in vivo; inhibitor; innovation; insight; methicillin resistant Staphylococcus aureus; microbial; mortality; mouse model; neutrophil; next generation; non-diabetic; non-healing wounds; novel; novel strategies; novel therapeutics; pathogen; pathogenic bacteria; pre-clinical; ramoplanin; resistant strain; response; scaffold; skin wound; soft tissue; synergism; targeted agent; uptake; wound

Project Summary/Abstract The effective treatment of bacterial infections of skin, deep soft tissues and wounds continues to be a major unmet challenge in healthcare settings, especially among patients with chronic diabetes. Staphylococcus aureus and Pseudomonas aeruginosa are the most common bacteria that are isolated from chronic, non- healing wounds. Antibiotic resistance has arisen in these particular bacteria, causing these infections to become increasingly difficult to treat and giving rise to multi-drug resistant strains, including Methicillin-resistant Staphylococcus aureus (MRSA). The goal of the proposed work is to develop the next generation of antimicrobials for which the design is inspired by a better mechanistic understanding of mammalian antimicrobial defense pathways. We focus our attention on the antimicrobial activities of neutrophil extracellular traps (NETs), which use histones to kill or suppress microbial proliferation. The antimicrobial mechanism of histones has not been understood. The Siryaporn and Gross labs recently reported that the pairing of histones with an additional component found in NETs – the antimicrobial peptide (AMP) LL-37 (cathelicidin) – produces potent antimicrobial synergy. LL-37 forms pores in the bacterial membrane, which enable histones to enter the bacterium and interfere with gene expression. This has an irreversible bactericidal (killing) effect on bacteria. The work proposed here will exploit this discovery by identifying combinations of human histones and membrane-/cell wall-targeting antimicrobials (MTAs) that produce potent antimicrobial activity and synergy. The overall objective of the project is to better understand the mechanism of antimicrobial synergy between histones and MTAs, and to harness it to establish a class of new therapeutics for the treatment of skin infections and wounds. We will accomplish this objective by identifying combinations of human histones with LL-37 and other MTAs that produce the greatest antimicrobial activities and synergies. We will test these against S. aureus, P. aeruginosa, and communities of skin bacteria in vitro (Aim 1). We will attempt to augment the antimicrobial activity by engineering in factors that impact histone function in NETs, specifically chemical modification through citrullination and tethering histones to DNA fibers (Aim 2). To validate our approach, we will test the combinations of histones and MTAs identified in Aims 1 and 2 in a standardized mouse skin infection model (Aim 3). To additionally address the unmet challenge of treating skin infection and wounds in diabetes patients, we will perform the tests in a diabetic mouse model. The results of this work will provide a mechanistic understanding of antimicrobial synergy and develop a strategy to combat the rise of antibiotic resistance. The results of the study could create a new class of antimicrobial therapeutics for the treatment of skin infections and wounds in diabetic and non-diabetic patients. This would represent a game-changer in the approach to antimicrobial treatments.

项目概要/摘要 有效治疗皮肤、深层软组织和伤口的细菌感染仍然是一个难题 医疗机构尤其是慢性糖尿病患者面临的主要挑战。 金黄色葡萄球菌和铜绿假单胞菌是从慢性非致病性细菌中分离出来的最常见细菌。 这些特定细菌出现了抗生素耐药性，导致这些感染。 变得越来越难以治疗并产生多重耐药菌株，包括耐甲氧西林 金黄色葡萄球菌 (MRSA)。 拟议工作的目标是开发下一代抗菌药物，其设计 受到对哺乳动物抗菌防御途径更好的机制理解的启发，我们专注于我们的研究。 关注中性粒细胞胞外陷阱（NET）的抗菌活性，它利用组蛋白杀死或 抑制微生物增殖。组蛋白的抗菌机制尚不清楚。 Siryaporn 和 Gross 实验室最近报告称，组蛋白与在 NETs——抗菌肽（AMP）LL-37（抗菌素）——产生有效的抗菌协同作用。 在细菌膜上形成孔，使组蛋白能够进入细菌并干扰基因 这对细菌具有不可逆的杀菌（杀死）作用。 这一发现是通过识别人类组蛋白和膜/细胞壁靶向抗菌剂的组合来实现的 （MTA）产生有效的抗菌活性和协同作用 该项目的总体目标是更好地发挥作用。 了解组蛋白和 MTA 之间的抗菌协同作用机制，并利用它来建立 一类用于治疗皮肤感染和伤口的新疗法。 我们将通过鉴定人类组蛋白与 LL-37 和其他组蛋白的组合来实现这一目标 我们将针对金黄色葡萄球菌、假单胞菌进行测试，以产生最大的抗菌活性和协同作用。 铜绿假单胞菌和体外皮肤细菌群落（目标 1）。 通过工程设计影响 NET 中组蛋白功能的因素的活性，特别是化学修饰 通过瓜氨酸化和将组蛋白束缚到 DNA 纤维上（目标 2），我们将测试 在标准化小鼠皮肤感染模型中目标 1 和 2 中鉴定的组蛋白和 MTA 的组合 （目标 3）另外解决治疗糖尿病患者皮肤感染和伤口方面尚未解决的挑战， 我们将在糖尿病小鼠模型中进行测试。 这项工作的结果将提供对抗菌协同作用的机制理解并开发 对抗抗生素耐药性上升的策略该研究结果可能会创造出一类新的抗生素。 用于治疗糖尿病和非糖尿病患者皮肤感染和伤口的抗菌疗法。 这将改变抗菌治疗方法的游戏规则。