Examination of the Functional Role of Sca1+ Vascular Progenitor Cells following Vascular Injury

血管损伤后 Sca1 血管祖细胞功能作用的检查

• 批准号: 9192398
• 负责人: Adam J.T. Schuldt
• 金额: $ 6.64万
• 依托单位: NORTHWESTERN UNIVERSITY AT CHICAGO
• 依托单位国家: 美国
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-09-01 至 2018-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9192398
• 关键词: Angioplasty; Aorta; Arterial Injury; Arteries; Atherosclerosis; Blood Vessels; Bone Marrow; Bypass; Cardiac; Cardiovascular Diseases; Cause of Death; Cell Differentiation process; Cell Lineage; Cells; Coronary; Coronary Arteriosclerosis; Culture Media; Data; Developed Countries; Development; Diphtheria Toxin; Endarterectomy; Endothelial Cells; Environment; Exclusion; Expenditure; Exposure to; Fellowship; Genes; Genetic; Genetically Engineered Mouse; Goals; Green Fluorescent Proteins; Healthcare; Hyperplasia; In Vitro; Injury; Institution; Intervention; K-Series Research Career Programs; Label; Laboratories; Lead; Leukocyte Chemotaxis; Mediating; Mentors; Methods; Modeling; Morbidity - disease rate; Mus; National Research Service Awards; Nitric Oxide; Outcome; Peripheral; Peripheral arterial disease; Physicians; Platelet Aggregation Inhibition; Population; Positioning Attribute; Procedures; Process; Property; Research; Risk; Role; Scientist; Secure; Smooth Muscle Myocytes; Stem cells; Stents; Stroke; Tamoxifen; Therapeutic; Time; Tissues; Tumor Debulking; Tunica Adventitia; United States National Institutes of Health; Vascular Smooth Muscle; Work; behavioral study; cardiac repair; career; cell killing; cell type; femoral artery; genetic technology; inhibitor/antagonist; innovation; intima media; migration; mouse model; novel therapeutics; prevent; response to injury; restenosis; skills; vascular smooth muscle cell proliferation

PROJECT SUMMARY/ABSTRACT Cardiovascular disease is the leading cause of death and stroke in developed countries. Long-term outcomes following treatments for severe atherosclerosis are limited by the development of neointimal hyperplasia leading to restenosis of the vessel. Thus, there is a need for better and more durable therapies to prevent restenosis after vascular interventions. Nitric oxide (NO) is a potent inhibitor of neointimal hyperplasia. While much is known about how NO regulates the arterial injury response, little is known about how NO may regulate progenitor cells in this process. Preliminary data from our laboratory have shown that progenitor cells that reside in the adventitia, namely Sca1+ progenitor cells, increase in the intima and media following arterial injury. NO prevents this increase, while also redirecting differentiation of these cells toward endothelial cells. While Sca1+ progenitor cells have the capacity to differentiate into multiple cell types, including vascular smooth muscle cells and endothelial cells, their functional role in the development of neointimal hyperplasia is unknown. Thus, the goal of this proposal is to explore these unknowns. We hypothesize that resident adventitial Sca1+ progenitor cells differentiate into vascular smooth muscle cells and contribute to the development of neointimal hyperplasia following arterial injury, but that NO redirects differentiation of the resident Sca1+ cells toward an endothelial cell lineage, thereby limiting the development of neointimal hyperplasia. To investigate this hypothesis, our Specific Aims are: 1) to examine the effect of nitric oxide on Sca1+ vascular progenitor cells in vitro, by exposing cultured Sca1+ progenitor cells to differentiation media with and without NO and quantifying smooth muscle and endothelial cell differentiation. 2) To investigate the migration and phenotypic fate of Sca1+ vascular progenitor cells in response to injury ± NO exposure. Specifically, we will track the fate of Sca1+ cells after vascular injury by permanently labeling Sca1+ cells with green fluorescent protein using a Cre-lox mouse model. Mice will then undergo femoral artery wire injury ± NO exposure in order to study the behavior and fate of Sca1+ progenitor cells after vascular injury. 3) To determine the functional role of Sca1+ vascular progenitor cells in the development of neointimal hyperplasia. Specifically, we will study the effect of loss of Sca1+ cells using a genetically engineered mouse that will selectively and temporally eliminate Sca1+ progenitor cells by expressing diphtheria toxin once the Sca1 gene is activated. Femoral artery wire injury will be performed on these mice ± NO. Successful completion of the studies described in this proposal will elucidate the role of Sca1+ progenitor cells in the development of neointimal hyperplasia and restenosis. This research may lead to the development of novel therapeutics that regulate Sca1+ progenitor cells following vascular procedures to prevent restenosis. Execution of these studies will help me to gain the skills necessary to develop as an independent physician-scientist.

项目总结/摘要 心血管疾病是发达国家死亡和中风的主要原因。长期结局 严重动脉粥样硬化的后续治疗受到新生内膜增生发展的限制 导致血管再狭窄。因此，需要更好和更持久的疗法来预防 血管介入术后再狭窄。一氧化氮（NO）是一种有效的新生内膜增生抑制剂。而 关于NO如何调节动脉损伤反应，我们知道得很多，但关于NO如何调节动脉损伤反应， 祖细胞在这个过程中。我们实验室的初步数据显示， 存在于外膜中，即Sca 1+祖细胞，动脉粥样硬化后内膜和中膜中的Sca 1+祖细胞增加， 损伤NO阻止这种增加，同时也将这些细胞的分化重新定向为内皮细胞。 虽然Sca 1+祖细胞具有分化成多种细胞类型的能力，包括血管内皮细胞，但它们具有分化成血管内皮细胞的能力。 平滑肌细胞和内皮细胞，它们在新生内膜增生的发展中的功能作用是 未知因此，本提案的目标是探索这些未知数。我们假设 外膜Sca 1+祖细胞分化为血管平滑肌细胞，并有助于血管平滑肌细胞的形成。 动脉损伤后新生内膜增生的发展，但NO重定向分化， 常驻的Sca 1+细胞向内皮细胞谱系发展，从而限制了 新生内膜增生为了研究这一假设，我们的具体目标是：1）检查 一氧化氮对体外Sca 1+血管祖细胞的影响，通过将培养的Sca 1+祖细胞暴露于 在含有和不含NO的分化培养基中，对平滑肌和内皮细胞分化进行定量。 2)研究Sca 1+血管祖细胞在不同浓度下的迁移和表型命运， 损伤±无暴露。具体地说，我们将通过永久性地观察血管损伤后Sca 1+细胞的命运， 使用Cre-lox小鼠模型用绿色荧光蛋白标记Sca 1+细胞。然后小鼠将经历 股动脉钢丝损伤± NO暴露，以研究Sca 1+祖细胞的行为和命运， 血管损伤3)为了确定Sca 1+血管祖细胞在血管生成中的功能作用， 新生内膜增生的发展。具体地说，我们将研究Sca 1+细胞损失的影响， 一种基因工程小鼠，其将通过以下方式选择性地和暂时地消除Sca 1+祖细胞： 一旦Sca 1基因被激活，就表达白喉毒素。股动脉导丝损伤将在 成功完成本提案中描述的研究将阐明 sca 1+祖细胞在新生内膜增生和再狭窄中的作用。这项研究可能会导致 在血管手术后调节Sca 1+祖细胞的新疗法的开发， 防止再狭窄。这些研究的执行将帮助我获得必要的技能，以发展为一个 独立的物理学家和科学家