The Role of Interleukin-2 in Vascular Smooth Muscle Cell Homeostasis

IL-2 在血管平滑肌细胞稳态中的作用

• 批准号: 8059693
• 负责人: Lucile E Wrenshall
• 金额: $ 9.56万
• 依托单位: UNIVERSITY OF NEBRASKA MEDICAL CENTER
• 依托单位国家: 美国
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-04-12 至 2011-08-15
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8059693
• 关键词: Actins; Address; Affect; Aneurysm; Apoptosis; Arterial Fatty Streak; Arteries; Atherosclerosis; Binding; Biological Assay; Biology; Blood Vessels; Bypass; Carbohydrates; Cardiovascular Diseases; Cell Proliferation; Cell physiology; Cells; Cellular biology; Cessation of life; Chemistry; Country; Development; Digestion; Disease; Drug Delivery Systems; Dyes; Enzymes; Exhibits; Failure; Functional disorder; Future; Generations; Goals; Heparitin Sulfate; Homeostasis; Human; Human Pathology; Hyperplasia; Immunology; Impairment; Individual; Interleukin-2; Knockout Mice; Knowledge; Label; Laboratories; Lead; Learning; Location; Lymphocyte; Maintenance; Measures; Mission; Modeling; Morphology; Mus; Oligosaccharides; Operative Surgical Procedures; Organ Transplantation; Pathologic; Pathology; Pathway interactions; Phenotype; Play; Prevalence; Prevention; Process; Proteoglycan; Public Health; Qualifying; Reagent; Regulation; Research; Role; Rupture; Shapes; Smooth Muscle Myocytes; Specimen; Testing; Therapeutic; Therapeutic Intervention; Tissues; Transplantation; United States; Vascular Diseases; Veins; Venous; Western Blotting; Work; base; design; heparanase; human disease; human tissue; in vivo; inhibitor/antagonist; innovation; insight; mortality; novel; novel therapeutics; polysulfated glycosaminoglycan; prevent; public health relevance; response; restenosis; therapeutic development; therapy design; vascular smooth muscle cell proliferation

DESCRIPTION (provided by applicant): Control of smooth muscle cell proliferation plays a critical role in several pathologic conditions including atherosclerosis, aneurysms, transplant vasculopathy, restenosis following endo-surgical stenting of vessels, and failure of vein grafts. Although excess vascular smooth muscle cell (VSMC) proliferation is involved in neointimal hyperplasia, and apoptosis of VSMCs is involved in aneurysm formation and atherosclerotic plaque rupture, much information has yet to be learned about how SMC proliferation is controlled in vivo and how said control fails in disease processes. This gap in knowledge impedes the development of new therapeutic or preventative measures aimed at correcting SMC dysfunction. This laboratory has recently discovered that interleukin-2 (IL-2) contributes to the maintenance of VSMCs in vivo. The overall goal of this laboratory is to understand the regulation and function of IL-2, and how impairment of either contributes to human pathology. The object of this proposal is to begin to establish the impact of IL-2 on VSMC biology. The central hypothesis is that IL-2 promotes the survival and maintenance of a differentiated phenotype in vascular smooth muscle cells. This hypothesis will be tested by the following specific aims: Aim I: Establish how monomeric and multimeric IL-2 influence VSMC function. This aim will be accomplished through testing the influence of IL-2 on several standard assays of VSMC function. Aim II: Determine whether VSMC release heparan sulfate- bound IL-2 and whether the released IL-2 influences VSMC function. This aim will be achieved through the use of a transwell assay, in which VSMC are separated from pieces of artery. Release of IL-2 will be assessed and heparanase inhibitors will be used to determine the role of this enzyme. Aim III: Establish the influence of IL-2 on aneurysm formation in vivo. This aim will be accomplished by Western blot analysis of the forms of IL- 2 present in human aneurysm tissue specimens, and by determining whether IL-2 can reverse aneurysm formation in IL-2 deficient mice. The proposed work is innovative, because it capitalizes on the novel findings that IL-2 is associated with heparan sulfate oligosaccharides present within large and small arteries and that in these location heparan sulfate-bound IL-2 influences VSMC phenotypes and survival. Completion of the proposed studies will provide an enhanced understanding of how vascular cell homeostasis is regulated via a here-to-for unknown pathway initiated by IL-2. This contribution is significant because the regulation of vascular cell homeostasis underlies a multitude of vascular pathologies, yet therapeutic interventions targeting smooth muscle cells are extremely limited. Since cardiovascular disease is the number one cause of mortality in the United States, this work addresses the NIH's mission to treat human disease. Knowledge gained from both proposed and future studies will support the establishment of new therapeutics, drug delivery systems, and even tissue constructs that target or utilizes smooth muscle cells. PUBLIC HEALTH RELEVANCE: Abnormalities in vascular smooth muscle cells underlie many pathologic conditions including atherosclerosis, aneurysms, and failure of vein grafts and transplanted organs. The proposed studies concern gaining a better understanding of how proliferation and death is regulated in vascular smooth muscle cells in both normal and disease states. The proposed research is of great significance to public health, given the prevalence of cardiovascular disease in the United States.

描述（由申请人提供）：平滑肌细胞增殖的控制在多种病理状况中发挥着关键作用，包括动脉粥样硬化、动脉瘤、移植血管病、血管内外科支架置入后的再狭窄以及静脉移植失败。尽管过度的血管平滑肌细胞（VSMC）增殖与内膜增生有关，而VSMC的凋亡与动脉瘤形成和动脉粥样硬化斑块破裂有关，但关于体内SMC增殖如何被控制以及所述控制如何在疾病过程中失败的信息仍有待了解。这种知识差距阻碍了旨在纠正 SMC 功能障碍的新治疗或预防措施的开发。该实验室最近发现白细胞介素2（IL-2）有助于体内VSMC的维持。该实验室的总体目标是了解 IL-2 的调节和功能，以及其中任何一个的损伤如何影响人类病理学。该提案的目的是开始确定 IL-2 对 VSMC 生物学的影响。中心假设是 IL-2 促进血管平滑肌细胞的存活和分化表型的维持。该假设将通过以下具体目标进行检验： 目标 I：确定单体和多聚体 IL-2 如何影响 VSMC 功能。这一目标将通过测试 IL-2 对 VSMC 功能的几种标准测定的影响来实现。目标II：确定VSMC是否释放硫酸乙酰肝素结合的IL-2以及释放的IL-2是否影响VSMC功能。这一目标将通过使用 Transwell 检测来实现，其中将 VSMC 与动脉碎片分离。将评估 IL-2 的释放，并使用乙酰肝素酶抑制剂来确定该酶的作用。目标 III：确定 IL-2 对体内动脉瘤形成的影响。这一目标将通过对人动脉瘤组织样本中存在的IL-2形式进行蛋白质印迹分析，并确定IL-2是否可以逆转IL-2缺陷小鼠中的动脉瘤形成来实现。这项工作具有创新性，因为它利用了以下新发现：IL-2 与大动脉和小动脉中存在的硫酸乙酰肝素寡糖相关，并且在这些位置硫酸乙酰肝素结合的 IL-2 影响 VSMC 表型和存活。完成拟议的研究将加深人们对血管细胞稳态如何通过 IL-2 启动的未知途径进行调节的理解。这一贡献意义重大，因为血管细胞稳态的调节是多种血管病理的基础，但针对平滑肌细胞的治疗干预极其有限。由于心血管疾病是美国第一大死因，这项工作体现了 NIH 治疗人类疾病的使命。从拟议的和未来的研究中获得的知识将支持建立新的治疗方法、药物输送系统，甚至针对或利用平滑肌细胞的组织结构。 公众健康相关性：血管平滑肌细胞的异常是许多病理状况的基础，包括动脉粥样硬化、动脉瘤以及静脉移植物和移植器官的衰竭。拟议的研究旨在更好地了解正常和疾病状态下血管平滑肌细胞的增殖和死亡是如何调节的。鉴于美国心血管疾病的流行，这项研究对公众健康具有重要意义。