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省略标题

• 批准号: 7119529
• 负责人: EBO DERK DE MUINCK
• 金额: $ 39.04万
• 依托单位: DARTMOUTH COLLEGE
• 依托单位国家: 美国
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-09-22 至 2008-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7119529
• 关键词: CD antigens; angiogenesis; angiography; apoptosis; bioimaging /biomedical imaging; blood flow measurement; confocal scanning microscopy; electron microscopy; gene expression; genetically modified animals; heart function; heart ventricle; ischemia; laboratory mouse; laser capture microdissection; microarray technology; morphometry; myocardial infarction; pharmacokinetics; protein sequence; surface plasmon resonance; swine; synthetic peptide; three dimensional imaging /topography; vascular endothelium

DESCRIPTION (provided by applicant): Recent studies from our laboratory have demonstrated that angiogenic vasculature in the heart can be targeted and imaged using a synthetic peptide sequence consisting of asparagine-glycine-arginine (NGR). The vascular address for this homing sequence is a cell surface aminopeptidase, aminopeptidase N (APN) also known as CD13. In cardiac angiogenesis we have established, that CD13/APN is strongly up-regulated on endothelial cells in the neo-vasculature, and that it cannot be detected on quiescent vessels outside the angiogenic area. Furthermore, we have shown, using conjugates of NGR with different fluorescent molecules and with biotin, that cardiac neo-vessels can be targeted and imaged selectively with these conjugates. In other studies, we have shown that on endothelial cells CD13/APN is up-regulated in response to hypoxia, angiogenic growth factors (HIF-la, bFGF and VEGF). Based on these studies we propose to utilize this novel vascular address and the versatile NGR homing sequence to study the role played by the angiogenic vasculature that is identified by targeted imaging in the setting of myocardial infarction (MI), and in hind limb ischemia (HLI). In mouse MI and HLI models we will co-register NGR fluorescence intensity and tomography with 3D images of neo-vessels by micro-CT, 2 photon microscopy and serial histological sections together with indices of tissue perfusion, oxygenation and left ventricular (L.V.) function. Molecular characterization of neo-vessels that bind NGR, will be performed by using laser dissection microscopy to isolate endothelial cells that bind fluorescently labeled NGR and endothelial cells that do not bind NGR that will then be subjected to microarray expression analysis. Clinical applicability of NGR imaging will be tested with NGR-iron particles in a porcine model of myocardial ischemia and bio-distribution, pharmacokinetics and internalization will be studied in mice and by confocal and electron microscopy of live endothelial cells. (End of Abstract)

描述（由申请人提供）： 我们实验室的最新研究表明，可以使用由天冬酰胺 - 甘氨酸 - 精氨酸（NGR）组成的合成肽序列对心脏中的血管生成脉管系统进行靶向和成像。该归因序列的血管地址是细胞表面氨基肽酶N（APN），也称为CD13。在心脏血管生成中，我们已经确定了CD13/APN在新脉管系统的内皮细胞上强烈上调，并且在血管生成区域以外的静态血管上无法检测到它。此外，我们已经表明，使用NGR的共轭物与不同的荧光分子和生物素，可以将心脏新船尾靶向和与这些结合物进行选择性成像。在其他研究中，我们表明，在内皮细胞上，CD13/APN响应缺氧，血管生长因子（HIF-LA，BFGF和VEGF）上调。基于这些研究，我们建议利用这种新型的血管地址和多功能的NGR归巢序列来研究通过靶向成像在心肌梗死（MI）和Hind Limb Ischemia（HLI）中鉴定出的血管生成脉管系统的作用。在小鼠MI和HLI模型中，我们将通过微CT，2个光子显微镜和串行组织学切片以及组织灌注，氧合和左心室（L.V.）功能的3D图像进行NGR荧光强度和断层扫描。通过使用激光解剖显微镜分离荧光标记的NGR和不结合NGR的内皮细胞的内皮细胞，将进行结合NGR的新毒剂的分子表征，然后进行微阵列表达分析。 NGR成像的临床适用性将在心肌缺血的猪模型中用NGR铁颗粒进行测试，并且将通过小鼠，生物代动力学，药代动力学和内在化测试，并通过小鼠以及实时内皮细胞的共聚焦和电子显微镜进行研究。 （抽象的结尾）