Molecular Dissection of T Cell Anergy

T 细胞无反应性的分子剖析

• 批准号: 6779483
• 负责人: THOMAS F GAJEWSKI
• 金额: $ 22.37万
• 依托单位: UNIVERSITY OF CHICAGO
• 依托单位国家: 美国
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-07-01 至 2006-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6779483
• 关键词: Adenoviridae; Coxsackievirus; T cell receptor; T lymphocyte; anergy; diacylglycerols; gene expression; genetic regulation; laboratory mouse; leukocyte activation /transformation; microarray technology; monoclonal antibody; protein kinase; transfection /expression vector

DESCRIPTION (provided by applicant): Although immunologic tolerance is controlled in part through thymic deletion, mechanisms of peripheral tolerance must be in place to avoid autoreactive aggression of T cells that survive into the periphery. One proposed mechanism of peripheral tolerance is the process of clonal anergy, a hyporesponsive state resulting from engagement of the TCR in the absence of costimualtory signals. Although anergy has been studied for many years, the precise molecular mechanism to explain the functional defects in anergic T cells remains unclear. We previously demonstrated defective TCR-induced Ras/MAP kinase signaling in anergic T cells. Using a novel adenoviral transduction system, we recently have shown that constitutively active (CA) Ras restores IL-2 production and MAP kinase activation in anergized T cells, arguing that defective Ras activation is causally linked to hyporesponsiveness. To understand the mechanism for blunted Ras activity in anergic cells we performed a gene array screen that has identified several attractive candidates. One of these is diacylglycerol kinase (DGK). However, whether upregulated DGK is sufficient to explain all the features of anergy is not clear, and the role of other potential candidates is not known. In Specific Aim 1, whether upregulation of DGK is sufficient to explain all features of the anergic state will be investigated. These experiments will be facilitated by the use of Coxsackie and adenovirus receptor (CAR) transgenic T cells and adenoviral vectors encoding wildtype and kinase-dead DGK isoforms. In Specific Aim 2, other attractive gene candidates will be considered, focusing on Schlafen and CRTAM. Adenoviral constructs will be made to study whether normal T cell activation will be suppressed. Monoclonal antibodies will be generated against CRTAM to study regulation of protein expression and effects of ligation or blockade on T cell function. New candidates will also be identified using EST arrays. Ultimately, a complete understanding of the anergic state on the molecular level should guide the development of novel pharmacologic therapies to promote or reverse peripheral tolerance in vivo.

描述（由申请人提供）：尽管免疫耐受性是通过胸腺缺失部分控制的，但必须建立外周耐受性的机制，以避免生存到周围的T细胞的自动反应性侵袭。外围耐受性的一种提出的机制是克隆反感的过程，克隆耐药的过程是在没有Costimaktory信号的情况下由TCR参与而导致的低反应状态。尽管已经研究了多年的Anergy，但解释厌氧T细胞功能缺陷的精确分子机制尚不清楚。我们先前证明了厌氧T细胞中TCR诱导的RAS/MAP激酶信号传导缺陷。使用新型的腺病毒转导系统，我们最近表明，组成性活性（CA）RAS恢复了Energed T细胞中IL-2的产生和MAP激酶激活，认为有缺陷的RAS激活与低血压有因果关系。为了了解厌恶细胞中RAS活性的机制，我们进行了一个基因阵列筛选，该筛选已经确定了几个有吸引力的候选者。其中之一是二酰基甘油激酶（DGK）。但是，上调的DGK是否足以解释Anergy的所有特征尚不清楚，并且其他潜在候选者的作用尚不清楚。在特定的目标1中，将研究DGK的上调是否足以解释厌食状态的所有特征。通过使用编码野生型和激酶死的DGK同型的Coxsackie和腺病毒受体（CAR）转基因T细胞和腺病毒载体，将促进这些实验。在特定的目标2中，将考虑其他有吸引力的候选基因候选者，重点是Schlafen和CRTAM。将制作腺病毒构建体以研究是否会抑制正常的T细胞激活。将对CRTAM产生单克隆抗体，以研究结扎或阻断对T细胞功能的蛋白质表达和影响的调节。还将使用EST数组来确定新的候选人。最终，对分子水平上的厌食状态的完全理解应指导新型药理疗法的发展，以在体内促进或逆转外围耐受性。