MOLECULAR DYNAMICS IN RECEPTOR-MEDIATED PHAGOCYTOSIS

受体介导的吞噬作用的分子动力学

• 批准号: 3292236
• 负责人: NANCY L. THOMPSON
• 金额: $ 17.14万
• 依托单位: UNIV OF NORTH CAROLINA CHAPEL HILL
• 依托单位国家: 美国
• 财政年份: 1986
• 资助国家: 美国
• 起止时间: 1986-07-01 至 1994-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3292236
• 关键词: affinity chromatography; cell membrane; fluorescence microscopy; fluorescence spectrometry; immunoglobulin A; lipid bilayer membrane; macrophage; membrane activity; membrane lipids; membrane reconstitution /synthesis; molecular dynamics; phagocytosis; phospholipids; protein reconstitution; receptor; receptor binding; receptor mediated endocytosis; tissue /cell culture

One mechanism of immunological defense is phagocytosis, in which macrophage cells ingest and destroy pathogenic microorganisms. In receptor-mediated phagocytosis, antibody receptors on a macrophage cell surface recognize antibodies bound to a foreign target and signal the macrophage to begin ingestion. Proposed is an investigation of the molecular events that occur in the initial region of contact between a macrophage and a potential target that lead to the onset of ingestion. In the research, the surfaces of pathogenic targets will be modeled by substrate-supported planar membranes containing hapten- conjugated phospholipids, and the interactions of hapten-specific antibodies with the films will be characterized for different film and antibody properties. The molecular requirements for and effects of the antibody-mediated interaction of macrophage cells with the planar membranes will then be examined. In a complementary approach, macrophage cell surfaces will be modeled by substrate-supported planar membranes constructed either from isolated natural membrane fragments or from purified and reconstituted macrophage antibody receptors and the interaction of antibodies with these model membranes will be characterized. The requirements for and effects of the antibody-mediated interaction of haptenated targets with the planar membranes containing antibody receptors will then be determined. Molecular transport and interaction will be measured with techniques in fluorescence microscopy. High order fluorescence correlation spectroscopy is a new technique that will monitor the formation of molecular clusters. Total internal reflection fluorescence microscopy, which was recently developed specifically for surface phenomena, will measure the equilibrium and kinetic parameters of molecule-membrane adhesion and will monitor molecular orientation. Fluorescence photobleaching recovery will measure lateral and rotational mobility. This research will contribute to the present understanding of (1) molecular events in the macrophage-target contact region during the onset of receptor-mediated phagocytosis, (2) factors that affect protein lateral and rotational mobility in or on membranes, and (3) the physicochemical basis of cell-surface receptor clustering. Development and refinement of techniques in protein reconstitution and surface fluorescence microscopy will be applicable to membrane biophysics in general.

免疫防御的一种机制是吞噬作用，其中 巨噬细胞摄入并破坏致病性微生物。 在 受体介导的吞噬作用，巨噬细胞上的抗体受体 细胞表面识别与外靶的抗体，并且 向巨噬细胞发出信号以开始摄入。 提议的是一个 研究初始事件的分子事件 巨噬细胞与潜在目标之间的接触区域 导致摄入的发作。 在研究中，将建模致病靶标的表面 通过底物支撑的平面膜，含有触觉 共轭磷脂，以及触觉特异性的相互作用 与电影的抗体将以不同的薄膜为特征 和抗体特性。 分子要求和 抗体介导的巨噬细胞相互作用的影响 然后，将检查平面膜。 在 互补方法，将建模巨噬细胞表面 由底物支撑的平面膜，是由 孤立的天然膜碎片或纯化和 重构的巨噬细胞抗体受体和相互作用 这些模型膜的抗体将被表征。 这 抗体介导的相互作用的要求和影响 含有抗体的平面膜的触觉靶标 然后将确定受体。 分子传输和相互作用将通过 荧光显微镜中的技术。 高阶荧光 相关光谱是一种新技术，可以监视 分子簇的形成。 总内部反射 荧光显微镜，该显微镜最近是专门开发的 对于表面现象，将测量平衡和动力学 分子膜粘附的参数，并将监测分子 方向。 荧光光漂白恢复将测量 横向和旋转迁移率。 这项研究将有助于目前对（1）的理解 巨噬细胞靶向接触区域中的分子事件 受体介导的吞噬作用的发作，（2）影响的因素 蛋白质的横向和旋转迁移率或膜上的旋转迁移率，（3） 细胞表面受体聚类的物理化学基础。 蛋白质重构技术的发展和完善 表面荧光显微镜将适用于膜 一般而言，生物物理学。