FC RECEPTOR DEPENDENT NEUTROPHIL ACTIVATION

FC 受体依赖性中性粒细胞激活

• 批准号: 3455850
• 负责人: ELAHE T CROCKETT
• 金额: $ 10.99万
• 依托单位: UNIVERSITY OF MICHIGAN AT ANN ARBOR
• 依托单位国家: 美国
• 财政年份: 1991
• 资助国家: 美国
• 起止时间: 1991-07-01 至 1996-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3455850
• 关键词: biological signal transduction; cell adhesion; cell adhesion molecules; complement receptor; cytokine; enzyme mechanism; glycoproteins; human tissue; immune complex; immunofluorescence technique; immunoglobulin G; leukocyte activation /transformation; monoclonal antibody; neutrophil; phospholipase D; protein kinase C

DESCRIPTION (Adapted from Applicant's Abstract): Human neutrophils express several receptors for the Fc region of IgG molecule (FCRI, RII, and RIII) and receptors for the third component of complement, CRI and CRIII (CD11b/CD18). Although numerous studies have demonstrated that the integrity of these receptors is crucial in immune adherence and functional responses of neutrophils to different types of ligands, there is limited information regarding the effects of specific FcRs and CD11/CD18 molecules on neutrophil signal transduction pathways. Recent studies indicate that neutrophil adherence and function responses are modulated by a variety of cytokines released by leukocytes, endothelial cells, and parenchymal cells. Therefore in an effort to better define the relationship between FcR, CD11/CD18 adherence glycoproteins, and neutrophil functional responses, they propose to examine the 1) biochemical mechanisms by which specific FcRs initiate signal transduction pathways in stimulating neutrophil functional responses, 2) effect of FcR interactions with each other and with CD11/CD18 molecules on neutrophil signal transduction pathways and functional responses, 3) modulation of CD11/CD18 and FcR signal transduction mechanisms in neutrophils by cytokines TNF, GM-CSF, and INF-gamma and 4) role of the ligand size and extent and type of cross-linking of surface receptors on signal transduction pathways and functional responses. Using specific monoclonal antibodies, the biochemical signals and neutrophil response induced by immune complexes (ICs), and the ligation of each member of FcR and CD11/CD18 molecules will be examined. The effect of CD11/CD18 modulation by various ligands on the function of Fc receptors will also be studied. Monoclonal antibodies against FcRs, CD11/CD18 molecules and their respective ligands will be utilized, in free form, in conjugated form with dextran molecules, in particulate form attached to latex beads, and in non-phagocytosable form, to provide various sizes of ligands and induce different types of receptor crosslinking. In addition both soluble and surface bound ICs will be utilized. To define the signal mechanisms involved in cell activation, changes in intracellular calcium and IP3 levels, and the activity of protein kinase C and phospholipase D will be measured, along with the application of established inhibitors/ modulators of biochemical signals. The neutrophil functional responses such as 0-2 generation, lysosomal enzyme release and adherence of neutrophils to protein-coated surfaces and endothelial cells will be assessed. Standard immunofluorescent techniques and flow cytometry will be applied to quantitate surface receptor expression. It is anticipated that results of this study will provide novel insight into the interactions between FcRs and CD11/CD18 adherence glycoproteins as they relate to neutrophil activation and the potential role of selected cytokines in modulating their function. These studies will provide the basis for further investigation of neutrophil signal transduction pathways and the development of new therapeutic strategies for the treatment of inflammatory diseases.

描述（改编自申请人的摘要）：人类中性粒细胞表达 IgG分子FC区域的几种受体（FCRI，RII和RIII） 和补体，CRI和CRIII的第三个成分的受体 （CD11b/CD18）。 尽管许多研究表明 这些受体的完整性对于免疫依从性和功能至关重要 中性粒细胞对不同类型的配体的反应，有限 有关特定FCR和CD11/CD18分子的影响的信息 在中性粒细胞信号转导途径上。 最近的研究表明 中性粒细胞的依从性和功能反应由多种 白细胞，内皮细胞和实质细胞释放的细胞因子。 因此，为了更好地定义FCR之间的关系， CD11/CD18依从性糖蛋白和中性粒细胞功能反应， 他们建议检查1）特定的生化机制 FCR在刺激中性粒细胞中启动信号转导途径 功能响应，2）FCR相互作用相互作用的影响 与中性粒细胞信号转导途径上的CD11/CD18分子和 功能响应，3）调节CD11/CD18和FCR信号 细胞因子TNF，GM-CSF和 Inf-gamma和4）配体的大小，程度和类型的作用 在信号转导途径上的表面受体的交联和 功能响应。 使用特定的单克隆抗体， 免疫复合物诱导的生化信号和中性粒细胞反应 （ICS），以及FCR和CD11/CD18分子的每个成员的连接 被检查。 各种配体对CD11/CD18调制对 还将研究FC受体的功能。 单克隆抗体 针对FCR，CD11/CD18分子及其各自的配体将是 以自由形式以葡萄糖分子共轭形式使用， 附着在乳胶珠的颗粒形式，并以不可刺激形式形式 提供各种尺寸的配体并诱导不同类型的受体 交联。 另外，可溶性和表面结合的IC将是 利用。 为了定义与细胞激活有关的信号机制， 细胞内钙和IP3水平的变化以及 将测量蛋白激酶C和磷脂酶D 生化信号的已建立抑制剂/调节剂的应用。 中性粒细胞功能反应，例如0-2代，溶酶体 酶释放和中性粒细胞对蛋白质包被的表面和 将评估内皮细胞。 标准免疫荧光技术 和流式细胞仪将用于定量表面受体 表达。 预计这项研究的结果将提供 对FCR与CD11/CD18依从性之间相互作用的新洞察力 糖蛋白与中性粒细胞激活相关的糖蛋白和潜力 选定的细胞因子在调节功能中的作用。 这些研究 将为中性粒细胞信号进一步研究提供基础 转导途径和开发新的治疗策略 炎症性疾病的治疗。