Staphylococcal Superantigen Interactions With Vaginal Epithelium

葡萄球菌超抗原与阴道上皮的相互作用

• 批准号: 8080418
• 负责人: Marnie L Peterson
• 金额: $ 28.92万
• 依托单位: UNIVERSITY OF MINNESOTA
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-07-13 至 2013-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8080418
• 关键词: Affect; Amino Acids; Area; Asthma; Atopic Dermatitis; Bacteria; Binding; Biological Models; Blood Circulation; Cells; Collaborations; Cytolysins; Cytotoxin; Data; Dermatitis; Development; Disease; Dose; Environment; Epithelial; Epithelial Cells; Epithelial Receptor Cell; Epithelium; Event; Exotoxins; Exposure to; Family suidae; Fever; Goals; Health; Human; Immune system; Infection; Inflammation; Inflammatory; Intestines; Iowa; Knock-out; Knowledge; Lead; Life; Mediating; Microbe; Minnesota; Modeling; Mucous Membrane; Organism; Pathogenesis; Pathology; Penetration; Permeability; Pneumonia; Principal Investigator; Production; Property; Proteins; Receptor Cell; Reporting; Research; Research Personnel; Resources; Rhinitis; Role; Secondary to; Shock; Signal Pathway; Signal Transduction; Signaling Molecule; Site; Skin Tissue; Soft Tissue Infections; Staphylococcal Infections; Staphylococcus aureus; Streptococcal Infections; Structure; Submucosa; Superantigens; Surface; Syndrome; T-Cell Activation; T-Lymphocyte; Testing; Therapeutic; Thick; Tissues; Toxic Shock Syndrome; Toxic Shock Syndrome Toxin-1; Toxic effect; Toxin; United States; Vagina; Work; base; cytokine; cytotoxic; experience; human disease; improved; innovation; interest; macrophage; microbial; mutant; novel; novel strategies; novel therapeutics; perforin; prevent; programs; receptor; receptor binding; response; therapeutic development

DESCRIPTION (provided by applicant): The long-term goals of this research are to understand how Staphylococcus aureus and its superantigens (SAgs), cytotoxins, and other exoproteins interact with mucosal surfaces to facilitate SAg penetration to cause serious human illnesses. We propose to use the vaginal epithelium as the model multi-layered mucosal surface, and hypothesize the data obtained in planned studies will also be applicable to other mucosal surfaces. Prior results using an ex vivo porcine vaginal permeability model indicate that the SAg, TSST-1, traverses mucosal surfaces in small amounts, but localizes in higher amounts within the inner epithelium, possibly serving as a toxin reservoir. In the presence of staphylococcal 1-toxin, TSST-1 penetrated the full thickness of the vaginal mucosa in significantly higher amounts, with considerable TSST- 1 also remaining within the epithelium. We hypothesize that cytotoxic and inflammatory properties of staphylococcal cytotoxins and other exoproteins enhance penetration of TSST-1 to inner epithelial cells where TSST-1 binds to an undescribed epithelial cell receptor, triggering pro-inflammatory cytokine production. Base on these hypotheses we propose two specific aims: 1) To determine the contribution of S. aureus cytotoxins (exoproteins) in enhancing the penetration of TSST-1 across epithelial surfaces by causing cytolytic and/or inflammatory effects on epithelial cells, and 2) To determine TSST-1 receptor binding and the mechanism of TSST-1 stimulation of epithelial cells, leading to intracellular activation of signaling pathways with subsequent cytokine production. Our preliminary data suggest that the most likely candidate exoproteins to facilitate penetration of TSST-1 across mucosal barriers are cytotoxins, including 3-toxin, which we propose to study in depth through use of purified 3-toxin components and allelic replacement knockout strains. In the course of these studies, we will also study mucosal penetration and activities of a deletion [missing amino acids 1 to 72] mutant TSST-1 protein (13,000 MW vs. 22,000 MW wild-type TSST-1) that maintains superantigenicity and is associated with a rapidly progressive, 100% fatal, extreme pyrexia syndrome in humans. We believe the planned studies will clarify the mechanisms by which TSST-1 penetrates mucosal barriers to cause large numbers of human diseases. These studies may suggest novel therapeutic strategies to manage serious S. aureus illnesses. PUBLIC HEALTH RELEVANCE: The bacterium Staphylococcus aureus often initiates serious human diseases from the organism's colonization of mucous membranes, followed by secretion of potent exotoxins referred to as superantigens. Illnesses include toxic shock syndrome that may have both menstrual and non- menstrual forms, and that may affect thousands of humans each year in the United States. This application studies the mechanism by which superantigens penetrate mucosal surfaces, allowing S. aureus to cause life threatening toxic shock syndrome, and possibly suggesting novel strategies to prevent and manage such illnesses.

描述（由申请人提供）：本研究的长期目标是了解金黄色葡萄球菌及其超抗原（SAg）、细胞毒素和其他外蛋白如何与粘膜表面相互作用，以促进SAg渗透，从而导致严重的人类疾病。我们建议使用阴道上皮作为多层粘膜表面的模型，并假设在计划的研究中获得的数据也将适用于其他粘膜表面。先前使用离体猪阴道渗透性模型的结果表明，SAg，TSST-1，以少量穿过粘膜表面，但以较高的量定位在内上皮内，可能充当毒素库。在葡萄球菌1-毒素的存在下，TSST-1以显著更高的量穿透阴道粘膜的整个厚度，相当多的TSST- 1也保留在上皮内。我们假设葡萄球菌细胞毒素和其他外蛋白的细胞毒性和炎症特性增强了TSST-1渗透到内上皮细胞，其中TSST-1结合到未描述的上皮细胞受体，触发促炎细胞因子的产生。基于这些假设，我们提出了两个具体的目标：1）确定S的贡献。金黄色葡萄球菌细胞毒素（外蛋白）通过对上皮细胞引起细胞溶解和/或炎症作用而增强TSST-1穿过上皮表面的渗透，和2）确定TSST-1受体结合和TSST-1刺激上皮细胞的机制，导致信号传导途径的细胞内活化，随后产生细胞因子。我们的初步数据表明，最有可能的候选外蛋白，以促进渗透的TSST-1跨粘膜屏障的细胞毒素，包括3-毒素，我们建议深入研究，通过使用纯化的3-毒素成分和等位基因置换敲除菌株。在这些研究过程中，我们还将研究缺失[缺失氨基酸1至72]突变型TSST-1蛋白（13，000 MW vs. 22，000 MW野生型TSST-1）的粘膜渗透和活性，该突变型蛋白保持超抗原性，并与人类快速进行性、100%致死性、极度发热综合征相关。我们相信计划中的研究将阐明TSST-1穿透粘膜屏障导致大量人类疾病的机制。这些研究可能会提出新的治疗策略来管理严重的S。金黄色葡萄球菌病公共卫生关系：细菌金黄色葡萄球菌通常从生物体的粘膜定殖引发严重的人类疾病，随后分泌被称为超抗原的强效外毒素。疾病包括中毒性休克综合征，可能有月经和非月经的形式，并可能影响成千上万的人，每年在美国。本申请研究了超抗原穿透粘膜表面，使S。金黄色葡萄球菌引起危及生命的中毒性休克综合征，并可能提出新的战略，以预防和管理这类疾病。