Sprouty-2 Regulation of Signaling in Asthma

Sprouty-2 哮喘信号传导的调节

基本信息

批准号：
8630180
负责人：
Rafeul Alam
金额：
$ 39.63万
依托单位：
NATIONAL JEWISH HEALTH
依托单位国家：
美国
项目类别：
财政年份：
2014
资助国家：
美国
起止时间：
2014-07-15 至 2018-06-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8630180
关键词：
Abbreviations Address Affect Allergens Asthma CD28 gene CD3 Antigens CD4 Positive T Lymphocytes Cell Differentiation process Cell Proliferation Cells Chronic Chronic Disease Clinical Defect Development Disease Down-Regulation Endocytosis Epithelial Cells Extrinsic asthma Feedback Human Impairment In Vitro Inflammation Inflammatory Knock-out Knockout Mice Knowledge Ligands MAPK3 gene Maintenance Mediating Modeling Mus Outcome Output Patients Phenotype Play Public Health Recycling Regulation Reporting Resolution Role Signal Pathway Signal Transduction Signaling Molecule T-Lymphocyte Testing Th2 Cells Tissues Up-Regulation airway hyperresponsiveness airway inflammation anergy asthmatic patient base cell motility cytokine in vivo mouse model new therapeutic target novel prevent public health relevance receptor response signal processing ubiquitin ligase

项目摘要

Abstract Asthma is a chronic inflammatory disease of the airways where T cells manifest a biased Th2/Th17 differentiation and a hyperactive phenotype. The latter is associated with sustained intracellular signaling. Signaling processes are usually transient due to negative homeostatic regulation. There is a knowledge gap in our understanding of mechanisms that induce sustained signaling. We propose to delineate the mechanism of induction of sustained signaling in T cells from asthma. We have reported that the signaling molecule sprouty 2 (spry 2) plays an essential role in establishing a self-sustained signaling mechanism for ERK1/2. To address this further we have generated CD4 targeted spry 2 knockout mice. Spry2-/- T cells have increased Cbl-b and decreased Nedd4. The foregoing ubiquitin ligases antagonistically regulate TCR ubiquitylation, endocytosis, degradation and thereby, control TCR signaling output. As a consequence of these receptor proximal abnormalities spry2-/-T cells have impaired signaling and proliferation. These impairments become more pronounced following CD28 engagement. Spry2-/- T cells have impaired Th2/Th17 differentiation. They are unable to mount airway inflammation, hyperreactivity and remodeling in a mouse model of asthma. Based upon these preliminary results we hypothesize that spry 2 amplifies and prolongs T cell signaling by forming a tripartite regulatory network where spry 2 and Nedd4 antagonize the signal terminating action of Cbl-b. Spry2- driven amplification and sustenance of signaling is important for co-stimulation, Th2/Th17 differentiation and development of asthma. Under specific aim 1 we will examine the role of spry 2 in generating sustained signaling in T cells. We will define the scope of CD3- and especially CD28-induced signaling pathways that are regulated by spry 2. We will examine the contribution of Cbl-b and Nedd4 to the spry2 knockout phenotype. Specific aim 2 will study the importance of spry 2 for Th2 and Th17 cell differentiation in vitro and in vivo in spry2-/- mice. We will delineate the signaling mechanism by which spry 2 regulates Th2/Th17 differentiation. Under specific aim 3 we will delineate the role of spry 2 in inducing and sustaining inflammation in a mouse model of chronic asthma. We will examine if Cbl-b knockout reverses the spry2 knockout phenotype. Under specific aim 4 we will study the expression of spry 2 in CD4 T cells from asthmatic patients and examine its contribution to the hyperactive T cell phenotype and biased differentiation in asthma. These studies are important because they have uncovered a hitherto unknown regulatory network involving spry2, Cbl-b and Nedd4, which controls Th2/Th17 differentiation and development of asthma.

抽象的哮喘是一种慢性气道炎症性疾病，其中 T 细胞表现出 Th2/Th17 倾向分化和过度活跃的表型。后者与持续的细胞内信号传导有关。由于负稳态调节，信号传导过程通常是短暂的。存在知识差距我们对诱导持续信号传导机制的理解。我们建议划定机制诱导哮喘 T 细胞持续信号传导。我们报道了信号分子的萌芽 2 (spry 2) 在建立 ERK1/2 自我维持信号传导机制方面发挥着重要作用。致地址进一步，我们生成了 CD4 靶向 spry 2 基因敲除小鼠。 Spry2-/- T 细胞增加了 Cbl-b 和 Nedd4 减少。上述泛素连接酶拮抗调节TCR泛素化、内吞作用、降解，从而控制 TCR 信号输出。由于这些受体近端 spry2-/-T 细胞异常信号传导和增殖受损。这些缺陷变得更加 CD28 参与后宣布。 Spry2-/- T 细胞的 Th2/Th17 分化受损。他们是无法在哮喘小鼠模型中观察气道炎症、高反应性和重塑。基于根据这些初步结果，我们假设 spry 2 通过形成 spry 2 和 Nedd4 拮抗 Cbl-b 的信号终止作用的三方调节网络。斯普里2- 信号的驱动放大和维持对于共刺激、Th2/Th17 分化和哮喘的发展。在具体目标 1 下，我们将研究 spry 2 在产生持续的 T 细胞中的信号传导。我们将定义 CD3 诱导的信号通路（尤其是 CD28 诱导的信号通路）的范围受 spry 2 调控。我们将研究 Cbl-b 和 Nedd4 对 spry2 敲除的贡献表型。具体目标 2 将研究 spry 2 对 Th2 和 Th17 细胞体外分化的重要性 spry2-/- 小鼠体内。我们将描述 spry 2 调节 Th2/Th17 的信号传导机制差异化。在具体目标 3 下，我们将描述 spry 2 在诱导和维持炎症中的作用在慢性哮喘小鼠模型中。我们将检查 Cbl-b 敲除是否可以逆转 spry2 敲除表型。在具体目标 4 下，我们将研究哮喘患者 CD4 T 细胞中 spry 2 的表达并检查其对哮喘中过度活跃的 T 细胞表型和偏向分化的贡献。这些研究很重要，因为他们发现了一个迄今为止未知的涉及 spry2 的调控网络， Cbl-b 和 Nedd4，控制哮喘的 Th2/Th17 分化和发展。