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）：项目概要/摘要慢性伤口影响美国约650万患者，每年的医疗保健费用为250亿美元。由于不断上升的医疗保健费用、人口老龄化以及糖尿病和肥胖症发病率的上升，这种负担正在迅速增加。研究表明，生物膜有助于伤口慢性化，并且金黄色葡萄球菌是在慢性伤口生物膜中发现的普遍菌种;然而，生物膜如何有助于延迟的上皮再形成仍不清楚。最近的研究表明，S.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，推测亚硝酸盐S。金黄色葡萄球菌产生诱导KC坏死的可溶性因子;金黄色葡萄球菌生物膜产生介导KC中特异性凋亡途径的可溶性因子。将通过全面调查KC培养物暴露于生物膜条件培养基或无张力条件培养基的凋亡特征（包括磷脂酰丝氨酸易位和DNA片段化）来检验这一假设。接下来，还将分析KC培养物对内源性和/或外源性凋亡途径的诱导。KC凋亡的更具体的分子分析将采用大幅面定量聚合酶链反应阵列进行研究。最后，对S.将使用核磁共振和质谱分析鉴定金黄色葡萄球菌生物膜，并筛选鉴定的产物以确定它们是否是诱导凋亡的因子。本研究的目的包括鉴定S.金黄色葡萄球菌生物膜和诱导KC凋亡的特定细菌产物。识别明确定义的信号传导途径和诱导细胞凋亡的细菌产物可以为未来的慢性伤口治疗和诊断提供分子理论，这可能对患者健康产生重大影响。 公共卫生相关性：本研究的目的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。越来越多的人群正在或将受到与慢性伤口相关的发病率和死亡率的困扰，即使一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显著的社会贡献。