IBD--MUCOSA-SPECIFIC REGULATION OF IFN-GAMMA PRODUCTION

IBD--粘膜特异性的 IFN-γ 产生调节

• 批准号: 6288345
• 负责人: Stephan R. Targan
• 金额: $ 30.6万
• 依托单位: CEDARS-SINAI MEDICAL CENTER
• 依托单位国家: 美国
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-03-01 至 2005-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6288345
• 关键词: CD2 molecule; CD28 molecule; JAK kinase; T cell receptor; T lymphocyte; gene expression; genetic promoter element; human subject; human tissue; immunogenetics; immunopathology; immunoregulation; inflammatory bowel diseases; interferon gamma; interleukin 2; intestinal mucosa; introns; leukocyte activation /transformation; mucosal immunity; oligonucleotides; patient oriented research; phosphorylation; tissue /cell culture; transfection; tumor necrosis factor alpha

DESCRIPTION: (Adapted from the Applicant's Abstract): T-cell production of IFN-gamma plays an essential role in disease initiation and severity of disease in animal models and Crohn's disease. Mucosal T-cells are different from peripheral T-cells in several ways. Mucosal T-cells are muted responders to activation via the T-cell receptor and are CD2 pathway dominant. During the previous award period the investigators used their ability to transfect primary T-cells to show unique mucosa-specific mechanisms by which T-cells produced Th1 cytokines. They demonstrated a role for AP1 in CD2 transactivation of the IL-2 gene. They showed that enhanced IL-2 production by CD2/CD28 co-activated peripheral T-cells occurs through mRNA stabilization and trans-activation in peripheral T-cells, however, in mucosal T-cells this effect can be solely the result of mRNA stabilization. This difference is due to the lack of activation of the AP1 and CD28 response elements in the IL-2 promotor in mucosal cells. They demonstrated several mucosal-specific mechanisms of IFN-gamma regulation and identified a unique role for TNF-alpha in mucosal T-cell IFN-gamma regulation. They defined the lamina propria mononuclear cell factor which can prime T-cells to respond to TNF-alpha. Furthermore, they demonstrated different cis elements in the IFN-gamma promotor that are used for transactivation of the IFN-gamma gene and mucosal T-cells as compared to peripheral T-cells. Finally, they demonstrated for the first time the enhancer function of the first intronic region of the IFN-gamma gene that involves the JAK/STAT pathway in mucosal T-cells but not in peripheral T-cells. Because of the vital importance of IFN-gamma in disease related mucosal inflammation yet its critical role for host defense, the knowledge of mucosa-specific targets, which would selectively attenuate mucosal IFN-gamma production without eliminating, would be a significant accomplishment. The overall objective of this continuation proposal is to more precisely define the mucosal specific regulatory pathways that are important for IFN-gamma regulation in T-cells and to use this knowledge to design approaches to modify IFN-gamma production in a mucosa-specific manner. This will be accomplished by the following specific aims: To identify through fine promotor analysis positive and negative cis-regulatory regions within the IFN-gamma promotor in which transcriptional regulation in lamina propria mononuclear cells differ from that in peripheral blood lymphocytes focusing on the previously identified regions of -204 to -108 (enhancer) and -528 to -204 base pair (repressor). To determine the mucosa-specific mechanisms of regulating the first intronic region of the IFN-gamma gene. From the results of Aim 1 and Aim 2 design molecular approaches including transfection of antisense oligonucleotides and or dominant negative transacting factors to attenuate in vitro IFN-gamma promotor expression in a mucosal-specific manner.

描述：（根据申请人的摘要改编）： IFN-gamma在疾病开始和疾病严重程度中起着至关重要的作用 在动物模型和克罗恩病。粘膜T细胞不同于 外围T细胞有几种方式。粘膜T细胞是反应者 通过T细胞受体的激活，是CD2途径的主导性。在 以前的奖项期调查人员使用其转染的能力 T细胞显示出独特的粘膜特异性机制，T细胞产生Th1 细胞因子。他们证明了AP1在IL-2的CD2反式激活中的作用 基因。他们表明，CD2/CD28共激活IL-2的产生增强 周围T细胞通过mRNA稳定和反式激活发生 但是，外围T细胞，在粘膜T细胞中，这种效应只能是 mRNA稳定的结果。这种差异是由于缺乏激活 粘膜细胞中IL-2启动子中的AP1和CD28响应元件的。 他们证明了IFN-gamma调节的几种粘膜特异性机制 并确定了TNF-Alpha在粘膜T细胞IFN-Gamma中的独特作用 规定。他们定义了固定层单核细胞因子 Prime T细胞应对TNF-Alpha。此外，他们证明了不同的 IFN-gamma启动子中用于反式激活的元素 与周围T细胞相比，IFN-GAMMA基因和粘膜T细胞。最后， 他们首次证明了第一个的增强功能 IFN-GAMMA基因的内含子区域，涉及jak/stat途径 粘膜T细胞，但不在外周T细胞中。因为至关重要 IFN-Gamma在疾病相关的粘膜炎症中的关键作用 宿主防御，粘膜特定目标的知识，这将有选择地 衰减粘膜IFN-gamma生产而不消除，将是 重大成就。该延续建议的总体目标 是更精确地定义粘膜特定的调节途径 对于T细胞中的IFN-Gamma调节很重要，并将这些知识用于 设计方法以粘膜特异性方式修饰IFN-gamma生产。 这将通过以下具体目的来完成：通过 精细的启动子分析阳性和负顺式调节区域 IFN-gamma启动子在层次中转录调节 单核细胞与关注的外周血淋巴细胞不同 以前确定的区域为-204至-108（增强器）和-528至-204 基对（阻遏物）。确定粘膜特异性机制 调节IFN-GAMMA基因的第一个内含子区域。从结果 AIM 1和AIM 2设计分子方法，包括反义转染 在 体外IFN-gamma启动子以粘膜特异性方式表达。