staphylococcus aureus biofilms mediate keratinocyte apoptosis

金黄色葡萄球菌生物膜介导角质形成细胞凋亡

• 批准号: 8366116
• 负责人: KELLY R KIRKER
• 金额: $ 7.2万
• 依托单位: MONTANA STATE UNIVERSITY - BOZEMAN
• 依托单位国家: 美国
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-07-01 至 2015-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8366116
• 关键词: ATM gene; ATM wt Allele; Abbreviations; Affect; Alkanesulfonates; Apoptosis; Apoptosis Inhibitor; Apoptotic; Biological Assay; Biology; Caring; Caspase; Cell Culture Techniques; Cell Death; Cells; Characteristics; Chronic; Coculture Techniques; Conditioned Culture Media; Culture Media; DNA Fragmentation; DNA Nucleotidylexotransferase; Data; Development; Diabetes Mellitus; Diagnostic; Fermentation; Fluorescein; Fluorescein-5-isothiocyanate; Future; Glyceraldehyde-3-Phosphate Dehydrogenases; Goals; Growth; Health; Health Care Costs; High Pressure Liquid Chromatography; Human; In Situ Nick-End Labeling; Incidence; Induction of Apoptosis; Infection; Investigation; Isothiocyanates; Label; Lead; Mammalian Cell; Mass Spectrum Analysis; Mediating; Metabolic; Metabolism; Methods; Microbial Biofilms; Microscopic; Molecular; Molecular Analysis; Molecular Biology; Montana; Morbidity - disease rate; NOESY; Necrosis; Nuclear Magnetic Resonance; Obesity; Outcome; Pathogenesis; Pathway interactions; Patients; Penicillins; Phosphate Buffer; Phosphatidylserines; Polymerase Chain Reaction; Population; Propidium Diiodide; Research; Research Personnel; Resources; Reverse Transcription; Saline; Signal Pathway; Skin; Sodium; Sodium Chloride; Spectrum Analysis; Staining method; Stains; Staphylococcus aureus; Streptomycin; TNF Receptor-Associated Factors; TNF gene; Techniques; Testing; Tetrazolium; Therapeutic Intervention; Time; Tumor Necrosis Factor-alpha; United States; Universities; Work; Wound Healing; aging population; apoptosis inducing factor; aspartyl-glutamyl-valyl-aspartyl-p-nitroanilide; aspartylglutamate; career; experience; gel electrophoresis; keratinocyte; killings; liquid chromatography mass spectrometry; metabolomics; multidisciplinary; nuclear Overhauser enhancement; prevent; response; small molecule; social; soy; stem; wound

DESCRIPTION (provided by applicant): PROJECT SUMMARY/ABSTRACT Chronic wounds affect approximately 6.5 million patients in the United States and represent $25 billion in annual health care costs. This burden is rapidly increasing due to escalating health care costs, an aging population, and the rising incidence of diabetes and obesity. Studies demonstrate that biofilms contribute to wound chronicity, and that Staphylococcus aureus is a prevalent species found in chronic wound biofilms; however, how biofilms contribute to the delayed re-epithelialization remains unclear. It was recently demonstrated that planktonic S. aureus and S. aureus biofilms have differential lethal effects on keratinocytes (KC). Therefore, it is hypothesized that planktonic S. aureus produce soluble factors that induce KC necrosis; whereas S. aureus biofilms produce soluble factors that mediate specific apoptotic pathways in KC. This hypothesis will be tested by comprehensively investigating KC cultures exposed to either biofilm-conditioned medium or planktonic-conditioned medium for apoptotic characteristics, including phosphatidylserine translocation and DNA fragmentation. Next, KC cultures will also be analyzed for the induction of the intrinsic and/or extrinsic apoptotic pathways. More specific molecular analysis of KC apoptosis will be investigated using a large format quantitative polymerase chain reaction array. Finally, bacterial products produced by S. aureus biofilms will be identified using nuclear magnetic resonance and mass spectrometry analysis, and the identified products will be screened to determine if they are apoptosis-inducing factors. The goals of this investigation include identifying the molecular pathways mediated by S. aureus biofilms and the specific bacterial products that induce KC apoptosis. Indentifying clearly defined signaling pathways and apoptosis- inducing bacterial products may provide a molecular rational for future chronic wound therapies and diagnostics, which may have a significant impact on patient health. PUBLIC HEALTH RELEVANCE: PROJECT NARRATIVE The goal of this investigation is to identify how Staphylococcus aureus biofilms kill one type of skin cell: the keratinocyte. This investigation will aid in the development of anti-biofilm therapies for the treatment of chronic wounds. A growing portion of the population is or will be afflicted with the morbidity and mortalit associated with chronic wounds, and even if a fraction of chronic wound cases stem from a microbial biofilm infection, the development of an anti-biofilm therapy would be a significant social contribution.

描述（由申请人提供）： 项目摘要/摘要 慢性伤口影响着美国大约 650 万名患者，每年造成 250 亿美元的医疗费用。由于医疗保健成本不断上升、人口老龄化以及糖尿病和肥胖症发病率上升，这一负担正在迅速增加。研究表明，生物膜会导致伤口慢性化，而金黄色葡萄球菌是慢性伤口生物膜中常见的菌种；然而，生物膜如何促进延迟的再上皮化仍不清楚。最近证明，浮游金黄色葡萄球菌和金黄色葡萄球菌生物膜对角质形成细胞（KC）具有不同的致死作用。因此，推测浮游金黄色葡萄球菌产生可溶性因子，诱导 KC 坏死；而金黄色葡萄球菌生物膜产生可溶性因子，介导 KC 中特定的细胞凋亡途径。这一假设将通过全面研究暴露于生物膜条件培养基或浮游条件培养基的 KC 培养物的细胞凋亡特征（包括磷脂酰丝氨酸易位和 DNA 片段化）来检验。接下来，还将分析 KC 培养物对内在和/或外在凋亡途径的诱导。将使用大幅面定量聚合酶链式反应阵列对 KC 细胞凋亡进行更具体的分子分析。最后，利用核磁共振和质谱分析对金黄色葡萄球菌生物膜产生的细菌产物进行鉴定，并对鉴定出的产物进行筛选以确定它们是否是细胞凋亡诱导因子。本研究的目标包括确定金黄色葡萄球菌生物膜介导的分子途径以及诱导 KC 凋亡的特定细菌产物。鉴定明确定义的信号通路和诱导细胞凋亡的细菌产物可能为未来慢性伤口治疗和诊断提供分子合理性，这可能对患者健康产生重大影响。 公共卫生相关性：项目叙述 本研究的目标是确定金黄色葡萄球菌生物膜如何杀死一种类型的皮肤细胞：角质形成细胞。这项研究将有助于开发用于治疗慢性伤口的抗生物膜疗法。越来越多的人正在或将要遭受与慢性伤口相关的发病和死亡的困扰，即使一小部分慢性伤口病例源于微生物生物膜感染，抗生物膜疗法的发展也将是一个重要的社会问题。贡献。