STRUCTURE/FUNCTION OF THE LYMPHOCYTE FCE RECEPTOR

淋巴细胞 FCE 受体的结构/功能

• 批准号: 6124172
• 负责人: DANIEL H CONRAD
• 金额: $ 28.33万
• 依托单位: VIRGINIA COMMONWEALTH UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 1989
• 资助国家: 美国
• 起止时间: 1989-05-01 至 2002-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6124172
• 关键词: B lymphocyte; CD antigens; antibody receptor; gel mobility shift assay; immediate hypersensitivity; immunoglobulin E; interleukin 4; laboratory mouse; nuclear factor kappa beta; protein biosynthesis; protein structure function; transcription factor

DESCRIPTION (Adapted from Investigator's abstract): This is a continuation application to study the involvement of the low affinity receptor for IGE (FceRII/CD23) in Type I allergy and inflammatory cytokine release. Two STAT6 sites have been identified in the murine CD23 gene; one in the promoter region of murine CD23a and another in intron-2 in the CD23b promoter equivalent region. The role of the two sites in cooperative upregulation of CD23 will be determined. In addition the role of a number of other DAN-binding protein motifs are present in the CD23a promoter. Special attention will be on murine transcription factor E3 (mTFE3) as knockout animals have no constitutive expression of CD23 and NFkB since destruction of the putative NFkB site has been shown to abrogate CD23 promoter reporter expression. The activity of this site for interaction with NFkB will be determined in gel shift and supershift assays and the potential for IL-4 to activate NFkB will be determined. CD23 plays a role in both oligomerization and potentially in interacting with IgE. This knowledge will be used to prepare oligomeric CD23 chimeras that have full IgE binding activity. Such constructs could potentially represent a novel method for isotype-specific regulation of IgE. Culture of B cells with membrane CD23 has been shown to inhibit B cell growth and Ig, especially IgE, production. Development of a soluble construct with full IgE-binding activity will allow the mechanism of this CD23-mediated effect to be studied in greater detail. Analysis of Ig production suggests that the order of sensitivity to high CD23 is IgE>IgG1>IgM and the observation that levels of germline transcript are not affected directs attention at post-switch development of the B cell. Special attention will be directed at the possibility that high CD23 can induce apoptosis in B cells and this will be examined in TUNEL or equivalent assays. Comparison of the effects of oligomeric vs monomeric sCD23 constructs will be performed. Finally, evidence has been obtained that an oligomeric sCD23 construct can induce IL-6 release from macrophages and macrophage cell lines. The structural characteristics of CD23 required for the inflammatory cytokine release will be determined. New knowledge from these studies may help in the development of new treatments for Type I allergy and for control of inflammatory cytokine release.

描述（改编自研究者的摘要）：这是延续 应用研究 IGE 低亲和力受体的参与 (FceRII/CD23) 在 I 型过敏和炎症细胞因子释放中的作用。 二 鼠 CD23 基因中已鉴定出 STAT6 位点；一个在 鼠 CD23a 的启动子区域和 CD23b 内含子 2 中的另一个启动子区域 启动子等效区域。 两个站点在合作中的作用 将确定CD23的上调。 另外还有一个数字的作用 CD23a 启动子中存在其他 DAN 结合蛋白基序。 将特别关注鼠转录因子 E3 (mTFE3)，因为 敲除动物没有 CD23 和 NFkB 的组成型表达，因为 破坏假定的 NFkB 位点已被证明可以消除 CD23 启动子报告基因表达。 本站互动活动 NFkB 将通过凝胶迁移和超迁移测定来确定，并且 将确定 IL-4 激活 NFkB 的潜力。 CD23发挥作用 寡聚化以及与 IgE 的潜在相互作用。 这 知识将用于制备寡聚 CD23 嵌合体，该嵌合体具有完整的 IgE 结合活性。 这种结构可能代表一种新颖的 IgE同种型特异性调节的方法。 B 细胞培养 膜 CD23 已被证明可以抑制 B 细胞生长和 Ig，尤其是 免疫球蛋白E，生产。 开发具有完全 IgE 结合的可溶性构建体 活性将允许研究这种 CD23 介导的效应的机制 更详细地说。 对 Ig 产生的分析表明， 对高 CD23 的敏感性是 IgE>IgG1>IgM，并且观察到 种系转录本不受影响，在转换后引起注意 B细胞的发育。 将特别关注 高 CD23 可能会诱导 B 细胞凋亡，这将是 通过 TUNEL 或同等检测进行检查。 效果比较 将进行寡聚与单体 sCD23 构建体的比较。 最后， 已经获得证据表明寡聚 sCD23 构建体可以诱导 IL-6 从巨噬细胞和巨噬细胞系中释放。 结构性 炎症细胞因子释放所需的 CD23 的特性 被确定。 这些研究中的新知识可能有助于发展 I 型过敏和控制炎症的新疗法 细胞因子释放。