B cell anergy, modified LDL uptake, and atherosclerosis

B 细胞无反应性、修饰的 LDL 摄取和动脉粥样硬化

• 批准号: 9886286
• 负责人: Elena V Galkina
• 金额: $ 48.39万
• 依托单位: EASTERN VIRGINIA MEDICAL SCHOOL
• 依托单位国家: 美国
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-04-01 至 2022-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9886286
• 关键词: Adoptive Transfer; Affect; Age; Aorta; Apolipoprotein E; Atherosclerosis; Attenuated; Autoantigens; B-Cell Activation; B-Lymphocyte Subsets; B-Lymphocytes; Cardiovascular Diseases; Cause of Death; Cell Survival; Cell physiology; Cells; Cellular biology; Cholesterol Homeostasis; Chronic; Complex; Data; Development; Disease; Disease Progression; Equilibrium; FRAP1 gene; Genes; Immobilization; Immune; Immune Tolerance; Immune response; Immune system; Inflammation; Inflammatory; Interleukin-4; Laboratories; Lipoproteins; Low-Density Lipoproteins; Malignant Neoplasms; Mature B-Lymphocyte; Mediating; Modeling; Molecular; Mus; Pathway interactions; Peripheral; Phenotype; Play; Prevention; Proteins; RNA delivery; Receptor Signaling; Receptors, Antigen, B-Cell; Regulation; Role; Shapes; Signal Transduction; Spleen; T-Cell Activation; T-Lymphocyte; TCF Transcription Factor; Testing; Transgenic Mice; Transgenic Organisms; Tyrosine Phosphorylation; Up-Regulation; Vascular Diseases; Viral Vector; Work; acetyl-LDL; aged; anergy; atherogenesis; atheroprotective; autoreactivity; chronic inflammatory disease; experimental study; in vitro Assay; inhibitor/antagonist; lymph nodes; macrophage; novel strategies; overexpression; oxidized low density lipoprotein; promoter; response; secondary lymphoid organ; small hairpin RNA; ubiquitin-protein ligase; uptake; virtual

Project Summary Cardiovascular disease is the leading cause of death worldwide. It is a multifaceted chronic inflammatory disease characterized by the accumulation of modified lipoproteins and immune cells in the aorta, vascular dysfunction, and low-grade chronic inflammation. Despite the strides that have been made in the past decade, there is still much that is unknown about the mechanisms behind disease progression. The uptake of modified low density lipoproteins (mLDL) by macrophages has been well characterized as being a major mechanism in the development of atherosclerosis. Our laboratory show that B cells can uptake mLDL and this uptake induces some significant phenotypical changes in B cells and upregulation of LXR-dependent targets. While mechanisms and role of mLDL uptake by Ms are well-characterized, the pathways of mLDL uptake in B cells are unclear and nothing is yet known about the impact of mLDL uptake on B cell functions. Our preliminary data suggest that acLDL uptake by B cells induces a unique gene profile, which supports inhibitory pathways including GRAIL. GRAIL is a well-known regulator for T-cell tolerance and T cell activation. Our data demonstrate that GRAIL is also expressed in B cells and play an important role in B cell activation and B cell anergy. Importantly, B cell-specific deficiency results in increased atherosclerosis. In Aim 1 of this application, we propose to test molecular mechanisms whereby GRAIL expression and mLDL uptake control B cell activation in atherosclerosis. First, we will test mechanisms of mLDL uptake by B cells using SR-B1, MARCO, CXCL16, and CD163 deficient mice or blocking Abs BCR-transgenic and FcRIIB- deficient mice. We will test how mLDL uptake induces some inhibitory pathways in B cells with the focus on LXR-mTOR-Otub1-GRAIL axis. Next, we will determine pathways by which GRAIL shapes B cell activation, investigate GRAIL-dependent BCR signaling, B cell survival and IL-4-dependent signaling in B cells, and examine the role of B cell specific GRAIL in atherosclerosis. In Aim 2, we will determine how atherosclerosis affects B cell anergy and test a role of GRAIL and mLDL uptake in stability and functions of anergic B cells. We will compare phenotypes of anergic B cells from young, aged Apoe-/- mice, and age-matched naturally occurring anergic BL/6 B cells. We will also test how atherosclerosis affects stability of anergic B cells in adoptive transfer experiments using Ars/A1 transgenic mice, a model of B cell anergy. Next, we will investigate how GRAIL affects B cell anergy and atherogenesis using Ars/A1 mice that would receive AAV–shRNA-Rnf128 under B cell specific promoter and AAV-PSCK9. The implications from this work are significant since the results will provide the first evidence for a role of mLDL uptake in B cell biology via GRAIL-dependent regulation of B cell anergy and B cell activation in atherosclerosis.

项目摘要 心血管疾病是全世界死亡的主要原因。它是一种多方面的慢性炎症 以修饰的脂蛋白和免疫细胞在主动脉、血管中积聚为特征的疾病 功能障碍和轻度慢性炎症。尽管在过去十年中取得了长足的进步， 关于疾病进展背后的机制仍有许多未知之处。改性的吸收 低密度脂蛋白（mLDL）的巨噬细胞已被充分表征为一个主要的机制， 动脉粥样硬化的发展。我们的实验室表明，B细胞可以摄取mLDL， 诱导B细胞中的一些显著表型变化和LXR依赖性靶点的上调。而 巨噬细胞摄取mLDL的机制和作用已得到充分表征，B细胞摄取mLDL的途径 目前尚不清楚，也不知道mLDL摄取对B细胞功能的影响。我们的初步 数据表明，B细胞对acLDL的摄取诱导了一种独特的基因谱，这支持了抑制途径 包括圣杯。GRAIL是众所周知的T细胞耐受性和T细胞活化的调节剂。我们的数据 证明GRAIL也在B细胞中表达，并在B细胞活化和B细胞增殖中起重要作用。 无反应重要的是，B细胞特异性缺陷导致动脉粥样硬化增加。在本申请的目标1中， 我们建议测试GRAIL表达和mLDL摄取控制B细胞的分子机制， 动脉粥样硬化中的激活。首先，我们将使用SR-B1，MARCO， CXCL 16和CD 163缺陷型小鼠或阻断Abs BCR转基因和Fc γ RIIB缺陷型小鼠。我们将测试 mLDL摄取如何在B细胞中诱导某些抑制途径，重点关注LXR-mTOR-Otub 1-GRAIL 轴线接下来，我们将确定GRAIL塑造B细胞活化的途径，研究GRAIL依赖的 BCR信号传导，B细胞存活和B细胞中IL-4依赖性信号传导，并检查B细胞特异性的作用。 动脉粥样硬化中的GRAIL。在目标2中，我们将确定动脉粥样硬化是如何影响B细胞无反应性的，并测试其作用 GRAIL和mLDL摄取在无能B细胞的稳定性和功能中的作用。我们将比较无反应性的 来自年轻、老年Apoe-/-小鼠的B细胞和年龄匹配的自然发生的无能BL/6 B细胞。我们还将 在使用Ars/A1的过继转移实验中测试动脉粥样硬化如何影响无反应性B细胞的稳定性 转基因小鼠，一种B细胞无反应性的模型。接下来，我们将研究GRAIL如何影响B细胞无反应性， 使用Ars/A1小鼠的动脉粥样硬化形成，所述小鼠将接受在B细胞特异性启动子下的AAV-shRNA-Rnf 128， AAV-PSCK 9.这项工作的意义是重大的，因为结果将提供第一个证据， mLDL摄取在B细胞生物学中的作用，通过GRAIL依赖性调节B细胞无反应性和B细胞活化， 动脉粥样硬化