ANTIGEN BINDING, CROSSLINKING & TRANSMEMBRANE SIGNALING

抗原结合、交联

• 批准号: 3133521
• 负责人: DAVID A HOLOWKA
• 金额: $ 13.25万
• 依托单位: CORNELL UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 1985
• 资助国家: 美国
• 起止时间: 1985-08-01 至 1993-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3133521
• 关键词: B lymphocyte; T cell receptor; T lymphocyte; antigen receptors; avidin; biological signal transduction; calcium flux; chemical binding; chemical reaction; crosslink; electron microscopy; haptens; hybridomas; immunoglobulin E; leukocyte activation /transformation; mast cell; membrane activity; membrane proteins; monoclonal antibody; protein kinase C; receptor binding; tissue /cell culture

A process of fundamental importance in immunology is the binding of antigen to cell surface-associated immunoglobulin that leads to transmembrane signaling in specialized cells. Antigen-mediated crosslinking of immunoglobulin E-receptor complexes on mast cells and basophils leads to degranulation in the allergic response, while crosslinking of surface immunoglobulin on B lymphocytes by certain antigens is a primary singal for proliferation and differentiation into antibody secreting cells. The critical molecular features of the crosslinking events that lead to a bioloogical response in either of these systems are not understood, and the proposed studies are aimed at elucidating these features. In previous studies on the IgE-receptor system, fluorescence methods have been developed that have allowed the kinetics of binding and crosslinking by model bivalent antigens to e determined. These studies have revealsed that some bivalent antigens can crosslink IgE-receptor complexes very efficiently on the cell surface, yet trigger only a small cellulr degranulation response. Properties such as rate of crosslinking, crosslink lifetime, and rate of dissociation for these antigens will be compared with those of other bivalent antigens that trighger a much stronger biological response. By this means the relationship between these kinetic properties, activation, and inactivation (densensitization) signals will be investigated. Structural factors also play a role in determining the efficacy of crosslinking, and these will be studied using model bivalent antigens of different lengths. Distances between IgE-receptor complexes crosslinked by long, rigid bivalent antigens that trigger degranulation will be mapped by electron microscopic and resonance energy transfer methods. The methodologies developed on the IgE-receptor system will be extended to studies of model antigen binding and crosslinking of dansyl-specific surface immunoglobulin on B cells and hybridoma cell lines. These studies will determine whether the features of crosslinking that are critical for signal tranduction by IgE- receptor complexes on mast cells are also important for transmembrane signaling by surface immunoglobulin on B cells.

免疫学中基本重要性的过程是具有约束力 与细胞表面相关的免疫球蛋白的抗原，导致 专用细胞中的跨膜信号传导。 抗原介导的 肥大细胞上免疫球蛋白电子受体复合物的交联 嗜碱性粒细胞导致过敏反应中的脱粒， 在B淋巴细胞上的表面免疫球蛋白交联 某些抗原是增殖和 分化为抗体分泌细胞。 关键 交联事件的分子特征，导致 这两个系统中的任何一个都不理解生物类学反应， 拟议的研究旨在阐明这些特征。 在先前关于IgE受体系统的研究中，荧光 已经开发了允许动力学的方法 通过模型二价抗原与E进行交联和交联 决定。 这些研究表明某些二价 抗原可以非常有效地交叉链接IgE受体复合物 细胞表面，但仅触发一个小的纤维素脱粒 回复。 诸如交联的交联速率之类的属性 这些抗原的生命周期和分离率将是 与其他二价抗原的抗原相比 更强的生物反应。 这意味着关系 在这些动力学特性，激活和失活之间 （密度）将研究信号。 结构 因素在确定的功效中也起作用 交联，将使用模型二价研究这些 不同长度的抗原。 IgE受体之间的距离 复合物通过触发的长而刚性的二价抗原交联 脱粒将通过电子显微镜和共振映射 能源传递方法。 在IgE受体系统上开发的方法将是 扩展到模型抗原结合和交联的研究 B细胞和杂交瘤上的Dansyl特异性表面免疫球蛋白 细胞系。 这些研究将确定是否的特征是否 交联对通过IgE信号扭曲至关重要 肥大细胞上的受体复合物对于 B细胞上表面免疫球蛋白的跨膜信号传导。