Imaging Apoptosis in vivo with Technetium 99m Annexin

使用 Technetium 99m 膜联蛋白对体内细胞凋亡进行成像

• 批准号: 6804089
• 负责人: FRANCIS Gerard BLANKENBERG
• 金额: $ 40.06万
• 依托单位: STANFORD UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-07-01 至 2008-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6804089
• 关键词: annexins; apoptosis; autoradiography; bioimaging /biomedical imaging; bioluminescence; brain disorder diagnosis; brain imaging /visualization /scanning; brain injury; cerebral artery; cerebral ischemia /hypoxia; flow cytometry; fluorescence microscopy; green fluorescent proteins; immunocytochemistry; laboratory mouse; laboratory rat; radionuclide imaging /scanning; single photon emission computed tomography; technetium

DESCRIPTION (provided by applicant): Phosphatidylserine (PS) is a membrane phospholipid that is selectively redistributed to a cell's outer surface during apoptosis. PS expression can be imaged with radiolabeled annexin V, an endogenous human protein, which has a high affinity for membrane bound PS in vivo. Despite extensive study there is much that is still not fully understood about annexin V imaging. In this proposal we will to determine the sensitivity, specificity, and reproducibility of technetium-99m (99mTc)-annexin V radionuclide imaging in two models of apoptosis; the first a rodent model of unilateral middle cerebral artery (MCA) ischemic injury, the second BCL-1 tumor bearing mice undergoing chemotherapy. In the first model we will address the sensitivity, test and retest variability of 99mTc-annexin V uptake in regions of neuronal injury following unilateral mild, moderate, and severe MCA stroke in rats with and without neuroprotective therapy. We will use a dedicated small animal microSPECT (single photon emission computed tomography) system for imaging. These data will be correlated with lesion(s) size and location(s) as defined by histologic analyses to permit calculation of the sensitivity and specificity of annexin V imaging for ischemia. Test and retest variability will be determined from two serial annexin V imaging studies performed within a 24 hour period. We will then study the BCL-1 syngeneic lymphoma cell line, a line engineered to express both GFP (green fluorescent protein) and luciferase for real time direct non-invasive visualization of tumor using BLI (bioluminescence imaging). We will first define the time course of annexin V uptake in the spleen following chemotherapy in BCL-1 tumor bearing mice with microSPECT, biodistribution and autoradiographic assays in relation to serial BLI measurements of tumor burden. Next we will use fluorescent (red)-annexin V co-injected with radiotracer in combination with flow cytometry, to directly quantify the number of tumor cells that are stressed (PS positive without features of apoptosis or necrosis), apoptotic or necrotic in response to chemotherapy and correlate these results with microSPECT for calculation of sensitivity and specificity of annexin V for tumor cell apoptosis. Completion of this proposal will aid in the design and planning of clinical trials that will study the use of serial annexin V imaging as a non-invasive marker of cellular injury and therapeutic efficacy.

描述（由申请人提供）： 磷脂酰丝氨酸（PS）是一种膜磷脂，在凋亡过程中选择性地重新分布在细胞的外表面。 PS表达可以用放射性标记的膜联蛋白V（一种内源性人蛋白）成像，该蛋白对体内膜结合的PS具有高亲和力。尽管进行了广泛的研究，但仍未完全了解膜联蛋白V成像。在此提案中，我们将确定Technetium-99M（99mtc）-Annexin v放射性核素成像在两种模型中的敏感性，特异性和可重复性；第一个单侧脑中动脉（MCA）缺血性损伤的啮齿动物模型，是接受化学疗法的第二个Bcl-1肿瘤轴承小鼠。在第一个模型中，我们将解决在有或没有神经保护疗法的大鼠中单侧轻度，中度和严重的MCA中风后神经元损伤区域中99mTC-Annexin v摄取99mTC-Annexin v摄取的敏感性，测试和重新验证敏感性，测试和重新验证可变异的敏感性，中度中度和严重MCA损伤中损伤中损伤中损伤中洛。中区域中洛。中区内中：我们将使用专用的小动物微光谱（单光子发射计算机断层扫描）进行成像。这些数据将与通过组织学分析定义的病变大小和位置相关，以计算与缺血的膜联蛋白V成像的敏感性和特异性。测试和重新差异将从在24小时内进行的两种串行膜联蛋白V成像研究确定。然后，我们将研究Bcl-1合成性淋巴瘤细胞系，该系设计用于表达GFP（绿色荧光蛋白）和荧光素酶，用于实时直接使用BLI（生物发光成像）对肿瘤进行直接非侵入性可视化。我们将首先定义与肿瘤负担的串行BLI测量相关的微光谱，生物分布和放射自显影测定的BCL-1肿瘤轴承小鼠的化疗后，在脾脏中的膜联蛋白V摄取的时间过程。接下来，我们将使用与流式细胞仪联合注入的荧光（红色） - 纳米蛋白V，直接量化压力的肿瘤细胞数量（PS阳性无凋亡或坏死的特征），凋亡或坏死的特征，对化学疗法的响应并与这些结果相关，并将这些结果与微观范围相关联，并将其与敏感性相关联。该提案的完成将有助于设计和计划临床试验，这些试验将研究连续膜剂V成像作为细胞损伤和治疗功效的非侵入性标志。