Retinal Imaging of Prognostic Indicators of Atherosclerosis

动脉粥样硬化预后指标的视网膜成像

• 批准号: 7573116
• 负责人: Frederick R Haselton
• 金额: $ 23.03万
• 依托单位: VANDERBILT UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-03-14 至 2011-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7573116
• 关键词: Address; Age; Animals; Antibodies; Aorta; Apolipoprotein E; Arterial Fatty Streak; Arteries; Atherosclerosis; Biological; Biological Markers; Biological Process; Biology; Blood Circulation; Blood Vessels; CCL2 gene; Cell Adhesion Molecules; Cell-Cell Adhesion; Cells; Clinic; Clinical; Code; Color; Complex; Connective Tissue; Deposition; Diagnosis; Diagnostic; Disease; Disease Progression; Endothelium; Evaluation; Experimental Designs; Fatty acid glycerol esters; Fibrin fragment D; Fluorescence; Harvest; Image; Imagery; Imaging Techniques; Immune; Immunofluorescence Immunologic; Immunohistochemistry; Infiltration; Inflammation; Inflammatory; Integrins; Intention; Label; Lesion; Leukocytes; Life; Link; Lipids; Magnetic Resonance Imaging; Measures; Mediator of activation protein; Medicine; Modeling; Molecular; Molecular Profiling; Monitor; Monocyte Chemoattractant Proteins; Morbidity - disease rate; Mus; Optics; Participant; Peptides; Positron-Emission Tomography; Property; Proteins; Quantum Dots; Reactive Oxygen Species; Resolution; Retina; Retinal; Risk; Rupture; Severities; Signal Transduction; Specimen; Staging; Surface; System; T-Lymphocyte; Techniques; Technology; Therapeutic Intervention; Time; Tissues; Ultrasonography; Vascular Cell Adhesion Molecule-1; Vascular Diseases; Western Blotting; Work; age group; antibody conjugate; atherogenesis; base; cell type; clinical application; fluorescence imaging; in vivo; inflammatory marker; macrophage; macrophage scavenger receptors; molecular imaging; monocyte; mortality; mouse model; nanocrystal; nanoscale; optical imaging; pre-clinical; prognostic; prognostic indicator; public health relevance; retina blood vessel structure

DESCRIPTION (provided by applicant): Atherosclerosis involves the participation of multiple biomolecular and cellular mediators. Current imaging techniques do not provide for the simultaneous imaging of these participants as they work in concert during vascular disease. We seek to utilize a fluorescence retinal imaging system to simultaneously image the expression of up to four cells and/or biomolecules in retinal vasculature in a model of atherosclerosis. Our imaging agents harness the optical properties of quantum dots (QD) linked to antibodies to color-code different biomarkers within the same imaging field. We hypothesize that visualization of abnormal molecular expression in retinal vasculature using our system has diagnostic and prognostic utility in the evaluation of atherosclerosis in biology and medicine. We propose to apply our retinal imaging strategy in conjunction with QD to detect inflammatory biomarkers in retinal vasculature in vivo, and to correlate expression levels with plaque severity in proximal aorta ex vivo in a mouse model of atherosclerosis. In Specific Aim 1 we propose to identify candidate biomarkers for atherosclerotic imaging in retinal vasculature. We will excise retinas from ApoE -/- mouse models of atherosclerosis and age-matched controls at 3 different age groups (6, 24, and 44 weeks) and use QD-antibody conjugates injected in vivo to detect the inflammatory markers VCAM-1, MCP-1, MSR, and dimerized fibrin (D-dimer) on plaque surfaces, which serve as relatively early and late indicators of atherosclerotic disease. In addition, isolated monocytes and T cells will be labeled ex vivo using spectrally-distinct QD and reinfused into mouse models and age-matched controls, and quantified in retinal tissue, to correlate cellular recruitment (a marker of lesion progression) with molecular expression. In the same animals, aortas will be harvested and probed for QD-labeled species and will be quantitatively assessed for immune cell infiltration and lipid content. In Specific Aim 2 we will perform in vivo imaging of retinal vasculature throughout atherosclerotic progression. We will inject QD-labeled antibodies and/or inflammatory cells developed in Aim 1 into ApoE -/- mouse models and age-matched controls and image the retinal vasculature in vivo to monitor molecular expression and cellular recruitment to inflammatory endothelium. Our experimental design will allow us to follow disease progression within a single animal over time. If our hypothesis is correct, this approach has clinical potential for non-invasively staging atherosclerosis based on molecular signatures. PUBLIC HEALTH RELEVANCE: Atherosclerosis is a complex disease involving multiple cell types and proteins in various stages of initiation, progression, and eventually plaque rupture which is responsible for mortality and morbidity. Many imaging strategies ranging from ultrasound to MRI have been developed with the intention of detecting atherosclerotic disease early, such that therapeutic interventions can slow progression before vulnerable plaques rupture. However, these approaches do not possess the resolution necessary to detect early lesions, and imaging of arteries located deep in the body, such as the aorta, can be difficult due to the presence of connective tissue and fat. Furthermore, current imaging strategies are not capable of detecting the spectrum of cell types and proteins present in plaques on vessel linings. The "molecular signature" of plaques, if detectable, would be particularly useful in diagnosis and treatment of atherosclerotic disease. For example, the presence of macrophages in lesions signals a relatively "late stage" plaque which is more likely to rupture, whereas certain proteins on the vessel wall, the cell adhesion molecules, may signal "early warning signs" to start treatment to curb risks. In this proposal, we seek to non-invasively image atherosclerosis in blood vessels using a retinal imaging system. Furthermore, we will use optical probes to color-code different biomarkers, such as cells and cell adhesion molecules, with distinct fluorescent emission spectra using semi-conducting nanocrystals or quantum dots. The retina offers a continuously-accessible, noninvasive window into the circulation, and can be used to rapidly and safely acquire the "molecular signature" of the blood vessels throughout the body in the clinic. We will measure fluorescence due to atherosclerosis-associated mediators in the retinal vessels, and correlate their expression with expression in other inaccessible but major arteries in the body, which are commonly prone to lesion formation. Proven biomarker correlates will then be imaged in vivo in a mouse model of atherosclerosis to validate the utility of our imaging approach.

描述（由申请人提供）：动脉粥样硬化涉及多个生物分子和细胞介质的参与。当前的成像技术在血管疾病期间共同起作用时，并不能同时对这些参与者进行成像。我们试图利用荧光视网膜成像系统同时在视网膜脉管系统中同时对四个细胞和/或生物分子的表达形象。我们的成像剂利用量子点（QD）的光学特性与与颜色代码在同一成像场中不同生物标志物的抗体相关。我们假设使用我们的系统在视网膜脉管系统中可视化异常的分子表达，在评估生物学和医学方面的动脉粥样硬化时具有诊断和预后效用。我们建议将视网膜成像策略与QD结合使用，以检测体内视网膜脉管系统中的炎症生物标志物，并在动脉粥样硬化模型中近端主动脉近端主动脉近端主动脉的斑块严重程度折叠表达水平。在特定目标1中，我们建议鉴定视网膜脉管系统中的动脉粥样硬化成像的候选生物标志物。 We will excise retinas from ApoE -/- mouse models of atherosclerosis and age-matched controls at 3 different age groups (6, 24, and 44 weeks) and use QD-antibody conjugates injected in vivo to detect the inflammatory markers VCAM-1, MCP-1, MSR, and dimerized fibrin (D-dimer) on plaque surfaces, which serve as relatively early and late indicators of动脉粥样硬化疾病。此外，分离的单核细胞和T细胞将使用光谱赋予的QD标记为离体，并重新融入小鼠模型和年龄匹配的对照中，并在视网膜组织中进行定量，以将细胞募集（病变进展的标记）与分子表达相关。在同一动物中，将收集主动脉并探测QD标记的物种，并将对免疫细胞浸润和脂质含量进行定量评估。在特定目标2中，我们将在整个动脉粥样硬化进展中对视网膜脉管系统进行体内成像。我们将在AIM 1中注入QD标记的抗体和/或炎症细胞中的APOE - / - 小鼠模型和年龄匹配的对照，并对体内视网膜脉管系统成像，以监测分子表达和细胞募集到炎性内皮的细胞。我们的实验设计将使我们能够随着时间的推移遵循单个动物的疾病进展。 如果我们的假设是正确的，则这种方法具有基于分子特征的非侵入性分期进行动脉粥样硬化的临床潜力。 公共卫生相关性：动脉粥样硬化是一种复杂的疾病，涉及多种细胞类型和蛋白质的启动，进展，最终导致死亡率和发病率的斑块破裂。从超声到MRI的许多成像策略是为了早期检测动脉粥样硬化疾病而开发的，因此治疗干预措施在易受伤害的斑块破裂之前可以放缓进展。但是，这些方法没有检测早期病变所需的分辨率，并且由于结缔组织和脂肪的存在，对体内深处（例如主动脉）的动脉成像可能很困难。此外，当前的成像策略无法检测容器衬里斑块中存在的细胞类型和蛋白质的光谱。斑块的“分子特征”，如果可以检测到，则在诊断和治疗动脉粥样硬化疾病方面特别有用。例如，病变中巨噬细胞的存在信号是一个相对“后期”的斑块，更有可能破裂，而血管壁上的某些蛋白质，细胞粘附分子，可能会向“预警信号”发出“预警信号”，以开始治疗以遏制风险。 在此提案中，我们试图使用视网膜成像系统在血管中非侵入性地对动脉粥样硬化形象。此外，我们将使用光学探针对不同的生物标志物（例如细胞和细胞粘附分子）进行色情探针，并使用半导体的纳米晶体或量子点具有独特的荧光发射光谱。视网膜在循环中提供了一个连续的，无创的窗口，可用于快速，安全地获取整个诊所中血管的“分子特征”。我们将由于视网膜血管中与动脉粥样硬化相关的介体引起的荧光，并将其表达与体内其他无法访问但主要的主要动脉相关，这些动脉通常易于病变形成。然后，经过验证的生物标志物相关性将在动脉粥样硬化的小鼠模型中在体内成像，以验证我们的成像方法的实用性。