ANTIGEN BINDING, CROSSLINKING & TRANSMEMBRANE SIGNALING

抗原结合、交联

• 批准号: 2671826
• 负责人: DAVID A HOLOWKA
• 金额: $ 21.04万
• 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 2002-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2671826
• 关键词: DNA; antibody receptor; biological signal transduction; cell membrane; crosslink; flow cytometry; hypersensitivity; immunoglobulin E; mast cell; membrane activity; membrane lipids; phosphorylation; protein tyrosine kinase; receptor binding; tissue /cell culture

The proposed studies will advance elucidation of the features of antigen-mediated crosslinking of lgE bound to its high affinity receptor, Fc epsilonRI, on mast cells that are critical for initiating a cascade of signaling events leading to the release of key modiators in allergic responses. The studies will build on strong foundation of fluorescence and other methodologies and concepts that are derived from previous work on this well-characterized model immune cell system. We have established that a small, symmetrical bivalent ligand stimulates a cellular response depending on whether this ligand forms small cyclic complexes or linear chains with lgE bound to Fc epsilon RI , providing evidence that structural restrictions between crosslinked lgE-Fc epsilon RI can limit cell activation. This hypothesis will be tested in Specific Aim 1 with a new generation of rigid bivalent ligands made with double-stranded DNA, together with a specially prepared bi- specific lgE. The structural arrangement of crosslinked lgE-Fc epsilon Rl beta and gamma subunits by Lyn, and the binding and activation of the tyrosine kinase Syk. Binding of trivalent and multivalent antigens will also be analyzed in conjunction with their functional activities. Specific Aim 2 will investigate the functional importance of specialized plasma membrane domains that are being characterized in this laboratory. Crosslinking of lgE-Fc epsilon Ri causes association with detergent-resistant membrane domains that contain abundant Lyn tyrosine kinase activity, and our recent results indicate that these interactions are important for initiating Fc epsilon Rl mediated signal transduction. These domain-Fc epsilon Rl interactions, their regulation by the mirofilament cytoskeleton, and the consequences of these on early and late signaling events will be investigated in biochemical preparations and intact cells. Because of the central role of ligand binding and receptor aggregation in immune cell activation and the accumulating evidence that signaling molecules localized to membrane domains are integrally involved, the proposed investigation should lead to new concepts and targets for therapeutic intervention.

拟议的研究将推动阐明的特征 LGE与其高亲和力结合的抗原介导的交联 受体FC Epsilonri，在肥大细胞上，对启动至关重要 一系列信号事件，导致键释放 过敏反应中的调节器。 研究将基于强大 荧光和其他方法和概念的基础 这是从以前在此特殊特殊的工作中得出的 模型免疫细胞系统。 我们已经确定了一个小的 对称的二价配体刺激细胞反应 取决于该配体是形成小环状复合物还是 带有LGE的线性链条绑定到FC Epsilon RI，提供证据 交联的LGE-FC Epsilon RI之间的结构限制 可以限制细胞激活。 该假设将以特定的 AIM 1与新一代的刚性二价配体制成 双链DNA，以及专门准备的双链DNA 特定的LGE。 交联的LGE-FC的结构布置 Lyn的Epsilon RL Beta和Gamma亚基，以及结合和 酪氨酸激酶SYK的激活。 三价和 多价抗原也将与其结合进行分析 功能活动。 特定目标2将研究功能 专门的质膜域的重要性 在这个实验室中被描述。 LGE-FC的交联 Epsilon RI导致与耐洗涤剂膜的关联 包含丰富Lyn酪氨酸激酶活性的域和 我们最近的结果表明，这些相互作用对 启动FC Epsilon RL介导的信号转导。 这些 域 - fc epsilon rl相互作用，它们的调节 单丝细胞骨架，以及这些对早期的后果 并将在生化中研究晚期信号事件 制备和完整的细胞。 由于配体的核心作用 免疫细胞激活中的结合和受体聚集 累积的证据表明信号分子本地 膜结构域是始终参与的 调查应导致新的概念和目标 治疗干预。