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省略标题

• 批准号: 6950738
• 负责人: EBO DERK DE MUINCK
• 金额: $ 39.98万
• 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/6950738
• 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。该归巢序列的血管地址是细胞表面氨肽酶，氨肽酶 N (APN) 也称为 CD13。在心脏血管生成中，我们已经确定，CD13/APN 在新血管系统的内皮细胞上强烈上调，并且在血管生成区域外的静止血管上无法检测到它。此外，我们已经证明，使用 NGR 与不同荧光分子和生物素的缀合物，可以用这些缀合物选择性地靶向心脏新生血管并成像。在其他研究中，我们已经表明，在内皮细胞上，CD13/APN 响应缺氧、血管生成生长因子（HIF-1a、bFGF 和 VEGF）而上调。基于这些研究，我们建议利用这种新型血管地址和多功能 NGR 归巢序列来研究血管生成脉管系统在心肌梗塞 (MI) 和后肢缺血 (HLI) 情况下通过靶向成像识别的作用。在小鼠 MI 和 HLI 模型中，我们将通过显微 CT、2 光子显微镜和连续组织切片以及组织灌注、氧合和左心室 (L.V.) 功能指标共同记录 NGR 荧光强度和断层扫描与新血管 3D 图像。结合 NGR 的新血管的分子表征将通过使用激光解剖显微镜来分离结合荧光标记的 NGR 的内皮细胞和不结合 NGR 的内皮细胞，然后进行微阵列表达分析。将使用 NGR 铁颗粒在猪心肌缺血模型中测试 NGR 成像的临床适用性，并将在小鼠中通过共聚焦和电子显微镜研究活内皮细胞的生物分布、药代动力学和内化。 （摘要完）