STREPTOCOCCUS MUTANS INTERACTION WITH ANIMAL TISSUES

变形链球菌与动物组织的相互作用

• 批准号: 3219586
• 负责人: MURRAY W STINSON
• 金额: $ 15.71万
• 依托单位: STATE UNIVERSITY OF NEW YORK AT BUFFALO
• 依托单位国家: 美国
• 财政年份: 1981
• 资助国家: 美国
• 起止时间: 1981-02-01 至 1991-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3219586
• 关键词: Streptococcus mutans; active immunization; adhesin; bacterial antigens; bacterial toxicology; basement membrane; cell membrane; cell wall; cross immunity; crosslink; dental caries vaccine; electron microscopy; human tissue; immunoelectrophoresis; immunofluorescence technique; immunoglobulin G; immunologic techniques; immunotoxicity; kidney cell; laboratory rabbit; laminin; membrane activity; microorganism culture; nephritis; oral bacteria; passive immunization; radiotracer; serology /serodiagnosis; skin; surface antigens; vascular endothelium; vascular endothelium permeability

Streptococcus mutans produces several components that bind to basement membranes and endothelial cells of kidney in vitro. These adhesins are secreted into the environment during growth and are also associated with the bacterial cell surface. It is believed that these substances may leach naturally into blood vessels of the oral cavity, or enter as a consequence of trauma to oral tissues or by parenteral immunization. In rabbits, the interaction of S. mutans components with kidney results in a severe nephritis that shows many histological, immunopathological, and serological features of streptococcus- associated nephritides in man. Pathogenesis may result from either direct toxicity of the tissue-bound adhesin or in situ activation of the complement cascade by the regular or alternative pathways. The long range goals of this project are to: a) understand the mechanisms of adhesin binding and pathogenesis; b) to improve the safety of prospective carries vaccines by assuring exclusion of these hazardous factors; c) devise prophylactic or therapeutic measures for streptococcus- associated nephritis. Specifically, the nature of the interactions between known S. mutans adhesions (LTA and proteins P57, P48, P40 and P30) and kidney components in vitro will be defined. The kidney-binding pattern of each purified adhesin will be characterized by immunofluorescence and immunoenzyme stains in light microscopy. Binding specificities of radiolabeled adhesins and the identities of the corresponding kidney components will be determined using isotopic dilution techniques and competitive inhibition assays using purified tissue components; e.g., laminin and heparan sulfate. Photoactivated crosslinking reagents will be used to covalently couple streptococcal protein to its kidney receptor which will then be isolated and characterized. The in vivo binding activities and pathogenic properties of purified S. mutans adhesins will be studied in a rabbit experimental model. The effects of infusion and perfusion of kidneys and intravenous injections of rabbits will be evaluated by microscopic analyses or renal biopsies using immunofluorescence, immunoenzyme and histological stains. Electron microscopy with immunogold labelling will also be used. In vivo experiments will also reveal the modulating effects of antibodies, complement and other serum components on adhesin binding. Finally, bacteria in dental plaque will be tested for both cell wall-associated and extracellular adhesins using immunofluorescence and electron microscopy.

变形链球菌产生多种成分，可结合 体外肾的基底膜和内皮细胞。 这些粘附素在生长过程中分泌到环境中 也与细菌细胞表面有关。 这是 相信这些物质可能会自然渗入血液 口腔血管，或由于外伤而进入 口腔组织或通过肠胃外免疫。 在兔子身上， 变形链球菌成分与肾脏的相互作用导致 严重的肾炎表现出许多组织学、 链球菌的免疫病理学和血清学特征 与男性相关的肾炎。 发病机制可能源于 组织结合粘附素的直接毒性或原位毒性 通过常规或 替代途径。 该项目的长期目标是 a) 了解粘附素结合的机制和 发病; b) 提高​​潜在承运人的安全性 确保排除这些有害因素来接种疫苗； c) 制定针对链球菌的预防或治疗措施 相关肾炎。 具体而言，相互作用的性质 已知的变形链球菌粘连（LTA 和蛋白质 P57、P48、 P40 和 P30) 和体外肾脏成分将被定义。 这 每个纯化的粘附素的肾脏结合模式将是 通过免疫荧光和免疫酶染色进行表征 在光学显微镜下。 放射性标记粘附素的结合特异性 相应的肾脏成分的身份将是 使用同位素稀释技术和竞争性测定 使用纯化的组织成分进行抑制测定；例如，层粘连蛋白 和硫酸乙酰肝素。 光活化交联剂将 用于将链球菌蛋白共价偶联至其肾脏 然后将分离并表征受体。 在 纯化的 S. 的体内结合活性和致病特性。 将在兔子实验模型中研究变形粘附素。 肾脏和静脉输液和灌注的影响 兔子的注射将通过显微镜分析或 使用免疫荧光、免疫酶和肾活检 组织学染色。 免疫金电子显微镜 还将使用标签。 体内实验也将揭示 抗体、补体和其他物质的调节作用 血清成分对粘附素结合的影响。 最后，牙齿中的细菌 将测试斑块的细胞壁相关性和 使用免疫荧光和电子技术检测细胞外粘附素 显微镜。