MR Signal Amplification for Receptor Imaging

用于受体成像的 MR 信号放大

基本信息

批准号：
7645768
负责人：
Alexei A Bogdanov
金额：
$ 34.85万
依托单位：
UNIV OF MASSACHUSETTS MED SCH WORCESTER
依托单位国家：
美国
项目类别：
财政年份：
2003
资助国家：
美国
起止时间：
2003-04-01 至 2011-06-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/7645768
关键词：
Abnormal Cell Achievement Address Adenocarcinoma Animal Model Animals Antibodies Antibody Therapy Binding Biological Markers Brain Cancer Model Cell Adhesion Molecules Cell physiology Cells Clinical Clinical Trials Detection Development Diabetes Mellitus Disease Disease Marker Disease Progression Early Diagnosis Enzymes Epidermal Growth Factor Receptor Fc Receptor Funding Future Genomics Goals Heart Diseases Human Image Imagery Imaging Device Imaging Techniques Immunoglobulin Fragments Immunohistochemistry In Vitro Inflammatory Response Label Laboratory Animals Laccase Lanthanoid Series Elements Lead Life Link Magnetic Resonance Imaging Malignant neoplasm of prostate Mediating Medical Medicine Modeling Molecular Molecular Probes Molecular Target Molecular Weight Monitor Nature Neoplasm Metastasis Non-Small-Cell Lung Carcinoma Organ Organism Oxidoreductase Patients Pattern Peroxidases Pharmaceutical Preparations Phenols Physicians Proteomics Protocols documentation Radioisotopes Research Resolution Safety Scientist Signal Transduction Site Specificity Substrate Specificity System TACSTD2 gene Testing Time Tissues Transgenic Model Translating Xenograft procedure base cancer cell design improved in vivo innovation macromolecule molecular imaging molecular marker monocyte neoplastic cell neutrophil novel novel marker overexpression polymerization public health relevance receptor receptor expression research study response scale up tool tumor

项目摘要

DESCRIPTION (provided by applicant): The pressing needs in translating recent achievements of genomic and proteomic screens ex vivo into the visualization of markers in living systems necessitate the development of novel molecular biomarker imaging techniques. The ability to apply molecular imaging to novel markers in vivo would have significant implications for early detection of disease, assessing patient-specific therapies and monitoring dynamic changes in expression patterns during disease progression. This application builds on our recent innovations in designing, testing and applying enzyme-mediated MR signal amplification strategy (MRamp) for imaging molecular targets. The proposed research is based on our observation that paramagnetic phenols in the presence of oxidoreductases give markedly enhanced relaxivity and MR signal. We previously proposed to harness MRamp effect and apply it for the needs of MR molecular imaging. As a result, we accomplished a transition of our research from in vitro level to in vivo experiments. Reaching the following milestones were instrumental in achieving the aims of the research: 1) designing and scaling up synthesis of MRamp substrates; 2) determining that the nature of aromatic reducing group linked to paramagnetic moiety defines substrate specificity and enzyme selectivity; 3) providing evidence that MRamp mechanism includes both polymerization and binding of paramagnetic oligomers to macromolecules; 4) optimizing a complete protocol for small conjugates of anti-receptor antibody and amplification enzymes ( binary amplification system ); 5) performing the testing of the developed system by using MRI in EGFR-expressing tumors; 6) testing alternative amplification enzymes and identifying a candidate for future research. By building on the above key findings we propose to achieve the following specific aims: Specific Aim. 1. Optimize and test in vivo single-enzyme targeted amplification imaging system. We hypothesize that MR signal amplification strategy could be improved by optimizing in vivo delivery. This can be achieved by using a) single, phenol- oxidizing enzyme covalently linked to F(ab')2 fragment of EGFR antibody. This hypothesis will be tested in EGFR-overexpressing tumor models. Specific Aim 2. Develop and test two-enzyme, bi-specific approach for imaging tumor cells co-expressing two different molecular markers. We hypothesize that by using two antibody fragments directed against different targets on the same cells we will image co-expression of adhesion molecule (EpCAM) and EGF receptor on non-small cell lung cancer (NSCLC) cells that are likely to respond to combined antibody therapy. This hypothesis will be tested in a model of NSCLC metastasis to the brain. Specific Aim 3. To use MRamp strategy for imaging inflammatory response and receptor repertoire of tumors in vivo. We hypothesize that monocyte/neutrophil component of inflammatory response can be imaged in tumors separately from receptors by using two MRamp substrates: the first having narrow myeloperoxidase specificity, and the second having laccase specificity. This hypothesis will be tested in transgenic model of prostate cancer. Public health relevance statement: The development of new drugs that can efficiently eliminate tumor cells or slow heart disease and diabetes requires ample testing in laboratory animals to prove safety and efficacy. The use of medical scanners that detect these cellular processes with high accuracy in live animals has the potential to significantly decrease the time between discovery of and subsequent clinical use of new medicines. This decreased time benefits both patients and taxpayers. We are proposing research approaches that will lead to the development of new tools (imaging drugs and compositions) for use with medical scanners. These tools will have applications for tracking the molecules that are linked to the abnormal cells. This research will help scientists and physicians to detect these cells and follow their response to medicines.

描述（由申请人提供）：将离体基因组和蛋白质组筛选的最新成果转化为生命系统中标记的可视化的迫切需要需要开发新型分子生物标记成像技术。将分子成像应用于体内新型标记物的能力将对疾病的早期检测、评估患者特异性疗法以及监测疾病进展期间表达模式的动态变化具有重要意义。该应用程序建立在我们最近在设计、测试和应用酶介导 MR 信号放大策略 (MRamp) 进行分子靶标成像方面的创新基础上。拟议的研究基于我们的观察，即在氧化还原酶存在下，顺磁性酚会显着增强弛豫度和 MR 信号。我们之前提出利用MRamp效应并将其应用于MR分子成像的需求。结果，我们完成了研究从体外水平到体内实验的转变。达到以下里程碑有助于实现研究目标：1）设计和放大 MRamp 基底的合成； 2)确定与顺磁性部分连接的芳香族还原基团的性质决定了底物特异性和酶选择性； 3）提供证据证明MRamp机制包括顺磁性低聚物的聚合和与大分子的结合； 4) 优化抗受体抗体和扩增酶的小缀合物的完整方案（二元扩增系统）； 5) 使用 MRI 在表达 EGFR 的肿瘤中对开发的系统进行测试； 6) 测试替代扩增酶并确定未来研究的候选者。基于上述主要发现，我们建议实现以下具体目标：具体目标。 1.体内单酶靶向扩增成像系统优化并测试。我们假设可以通过优化体内传递来改进 MR 信号放大策略。这可以通过使用a)与EGFR抗体的F(ab')2片段共价连接的单个酚氧化酶来实现。这一假设将在 EGFR 过表达肿瘤模型中得到检验。具体目标 2. 开发并测试双酶、双特异性方法，用于对共表达两种不同分子标记的肿瘤细胞进行成像。我们假设，通过使用针对同一细胞上不同靶点的两个抗体片段，我们将在可能对组合抗体产生反应的非小细胞肺癌 (NSCLC) 细胞上对粘附分子 (EpCAM) 和 EGF 受体的共表达进行成像治疗。这一假设将在非小细胞肺癌脑转移模型中得到检验。具体目标 3. 使用 MRamp 策略对体内肿瘤的炎症反应和受体库进行成像。我们假设，通过使用两种 MRamp 底物，可以将炎症反应的单核细胞/中性粒细胞成分与受体分开成像：第一个底物具有窄髓过氧化物酶特异性，第二个底物具有漆酶特异性。这一假设将在前列腺癌的转基因模型中得到检验。公共卫生相关声明：开发能够有效消除肿瘤细胞或减缓心脏病和糖尿病的新药需要在实验动物中进行充分的测试以证明安全性和有效性。使用医学扫描仪在活体动物中高精度检测这些细胞过程有可能显着缩短新药发现和随后临床使用之间的时间。时间的缩短对患者和纳税人都有利。我们提出的研究方法将导致开发用于医疗扫描仪的新工具（成像药物和组合物）。这些工具将用于追踪与异常细胞相关的分子。这项研究将帮助科学家和医生检测这些细胞并跟踪它们对药物的反应。