Modulating granulocytic myeloid-derived suppressor cell (G-MDSC) metabolic activity to promote Staphylococcus aureus biofilm clearance

调节粒细胞骨髓源性抑制细胞 (G-MDSC) 代谢活性以促进金黄色葡萄球菌生物膜清除

• 批准号: 10738662
• 负责人: Tammy L Kielian
• 金额: $ 23.03万
• 依托单位: UNIVERSITY OF NEBRASKA MEDICAL CENTER
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-06-15 至 2025-05-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10738662
• 关键词: Adoptive Transfer; Anti-Inflammatory Agents; Antibiotic Therapy; Antibiotics; Antiinflammatory Effect; Attenuated; Cardiac Myocytes; Cell physiology; Cells; Cellular Metabolic Process; Chronic; Coculture Techniques; Data; Development; Dyes; Endothelial Cells; Epithelial Cells; Excision; Exhibits; Exposure to; Extravasation; Future; Glycolysis; Glycolysis Inhibition; Goals; Health Care Costs; Human; Immune; Immune Evasion; Immunosuppression; Impaired cognition; Implant; In Vitro; Infection; Infiltration; Inflammatory; Inflammatory Response; Label; Laboratories; Leukocytes; Link; Macrophage; Mediating; Medical Device; Mesenchymal Stem Cells; Metabolic; Metabolic Pathway; Metabolism; Microbial Biofilms; Mitochondria; Modeling; Movement; Mus; Myeloid-derived suppressor cells; Myocardial Ischemia; Nanotubes; Operative Surgical Procedures; Oxidative Phosphorylation; PTPRC gene; Parkinson Disease; Pathologic; Pathology; Periprosthetic joint infection; Population; Property; Prosthesis; Reporting; Role; Shapes; Site; Source; Spinal cord injury; Staphylococcus aureus; T-Cell Activation; Tissues; Work; aerobic glycolysis; antibiotic tolerance; bactericide; cell type; chemotherapy; congenic; disability; granulocyte; humanized mouse; improved; in vivo; innovation; monocyte; mouse model; neutrophil; novel; novel strategies; novel therapeutic intervention; prevent; programs; superresolution microscopy; treatment strategy

Staphylococcus aureus (S. aureus) is a leading cause of biofilm-associated prosthetic joint infection (PJI) characterized by antibiotic tolerance and evasion of immune-mediated clearance. Our laboratory has established a critical role for granulocytic myeloid-derived suppressor cells (G-MDSCs), a pathologically activated neutrophil precursor, in attenuating monocyte/macrophage (MФ) proinflammatory properties and neutrophil bactericidal activity that leads to S. aureus biofilm persistence. The metabolic attributes of leukocytes are intimately linked with their inflammatory properties, relationships encompassing the emerging field of immunometabolism. This has been best described for MФs, where biases towards aerobic glycolysis or oxidative phosphorylation (OxPhos) dictate pro- vs. anti-inflammatory activity, respectively. In contrast, little information is available regarding the metabolic tendencies of G-MDSCs during infection and our preliminary studies are the first to demonstrate that G-MDSCs exhibit a glycolytic bias following S. aureus biofilm exposure in vitro and in vivo. Importantly, blocking glycolysis in G-MDSCs attenuated their suppressive activity resulting in decreased biofilm burden in vivo. This provides proof-of-concept that targeting G-MDSC metabolism is a tractable and novel approach to promote biofilm clearance. Recent studies have revealed that mitochondria can directly traffic between cells in vitro and in vivo via tunneling nanotubes (TNTs), where mitochondrial transfer in recipient cells promotes their OxPhos activity. However, most of these reports examined TNT-mediated mitochondrial transfer between mesenchymal stem cells and endothelial cells or cardiomyocytes, whereas this mechanism of intercellular metabolic rewiring has not been explored in the context of MФ-G-MDSC crosstalk. These studies will leverage MФs as a source of mitochondria for reprogramming G-MDSC metabolism, which originated from our prior work showing that MФ adoptive transfer reduced S. aureus biofilm burden in vivo. Indeed, our preliminary data support this innovative concept, where MФs transferred their mitochondria to G-MDSCs in a cell contact-dependent manner, which skewed G-MDSC metabolism towards OxPhos. This R21 revision will investigate the hypothesis that increasing mitochondrial abundance in G-MDSCs will result in metabolic reprogramming from glycolysis to an OxPhos bias coincident with diminished immune suppressive activity, resulting in improved biofilm clearance. Understanding how mitochondrial transfer from MФs can reprogram G- MDSC metabolism will be examined leveraging natural transfer and exogenous mitochondrial treatment paradigms in the following Specific Aims. 1) Identify the functional implications of mitochondrial transfer on G- MDSC anti-inflammatory activity and 2) Determine whether augmenting G-MDSC mitochondrial activity improves S. aureus clearance during PJI. These studies will inform our long-term goal of targeting critical metabolic nodes to reprogram aberrant leukocyte anti-inflammatory responses to eradicate biofilm together with antibiotics.

金黄色葡萄球菌(S.金黄色葡萄球菌）是导致生物膜相关性人工关节感染（PJI）的主要原因 其特征在于抗生素耐受性和免疫介导清除的逃避。我们的实验室已经建立了 粒细胞性髓源性抑制细胞（G-MDSCs），一种病理性活化中性粒细胞的关键作用 前体，在减弱单核细胞/巨噬细胞（MФ）促炎特性和嗜中性粒细胞杀菌中的作用 导致S.金黄色葡萄球菌生物膜持久性。白细胞的代谢属性与 与它们的炎性特性的关系包括免疫代谢的新兴领域。这 最好描述为MФs，其中偏向需氧糖酵解或氧化磷酸化 （OxPhos）分别指示促炎活性和抗炎活性。相比之下，几乎没有可用的信息 关于G-MDSCs在感染过程中的代谢趋势，我们的初步研究首次 证明G-MDSCs在S.金黄色葡萄球菌生物膜体外和体内暴露。 重要的是，阻断G-MDSCs中的糖酵解减弱了其抑制活性，导致生物膜减少 体内负荷。这提供了以G-MDSC代谢为靶点的概念证明，是一种易处理的新方法。 促进生物膜清除方法。最近的研究表明线粒体可以直接运输 通过隧道纳米管（TNTs）在体外和体内细胞之间进行，其中受体细胞中的线粒体转移 促进其OxPhos活性。然而，大多数这些报告检查了TNT介导的线粒体转移 间充质干细胞和内皮细胞或心肌细胞之间的相互作用，而这种机制 还没有在MФ-G-MDSC串扰的背景下探索细胞间代谢的重新布线。这些研究 将利用MФs作为线粒体的来源，对G-MDSC代谢进行重编程，这源于 我们先前的工作表明MФ过继转移降低了S。金黄色葡萄球菌生物膜负荷。的确，我们的 初步数据支持这一创新概念，即MФs将其线粒体转移到G-MDSCs， 细胞接触依赖性方式，使G-MDSC代谢偏向OxPhos。本R21修订版将 研究G-MDSCs中线粒体丰度增加将导致代谢 从糖酵解重编程为OxPhos偏性与免疫抑制活性降低一致， 导致生物膜清除率提高。了解MФs的线粒体转移如何对G- 将利用自然转移和外源性线粒体处理检查MDSC代谢 在以下具体目标中的范例。1)确定线粒体转移对G-细胞凋亡的功能影响 MDSC的抗炎活性和2）确定增加G-MDSC线粒体活性是否改善 S.在PJI期间清除金黄色葡萄球菌。这些研究将为我们的长期目标提供信息，即靶向关键代谢节点 以与抗生素一起根除生物膜。