Tracking Stem cells with IMAGEtags

使用 IMAGEtags 追踪干细胞

• 批准号: 7080430
• 负责人: Marit Nilsen-Hamilton
• 金额: $ 25.64万
• 依托单位: IOWA STATE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-09-20 至 2008-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7080430
• 关键词: DNA directed RNA polymerase; bioengineering /biomedical engineering; cell differentiation; cell migration; cell proliferation; embryonic stem cell; gene expression; laboratory mouse; molecular cloning; nucleic acid chemical synthesis; nucleic acid structure; oligonucleotides; reporter genes; stem cells; technology /technique development; tissue /cell culture; transfection /expression vector

DESCRIPTION (provided by applicant): To-date most real time imaging procedures have been used to detect cancer cells in vivo. The application of these methods may not be appropriate for stem cells for several reasons. First, the tracking systems include the expression in the cells to be tracked of a foreign protein that has the potential of altering stem cell behavior such as proliferation, differentiation, and migration. Second, the production of the foreign protein, often to reach many fold over the levels of other proteins in the cell, requires that the cell devote a significant portion of its energy to its synthesis. Although this is not likely to be a problem for cancer cells which generally express very high levels of hexokinase and glucose transporters for making ATP by glycolysis, stem cells are less robust and could be debilitated. For effective tissue repair, stem cells must migrate and proliferate in regions of previously damaged tissues that are often hypoxic and nutrient depleted. The additional need to synthesize a foreign protein from a constitutive promoter that cannot readily be down regulated will place an energy burden on the cells when they need to cope with an inadequate environment and may decrease the number of cells that can successfully populate the damaged tissue. Consequently, for marking stem cells, it would be of great advantage to have a system that does not place a large energy burden on the cells that are being imaged. The ultimate goal of the research proposed here is to develop an innocuous means of marking stem cells so that they can be tracked in vivo and in real time without their potential for homing, proliferation and differentiation being altered by the marking system. The current proposal describes a novel nucleic acid structure that will be expressed in cells to mark them so they can be tracked in vivo by available imaging technology. We call the markers "Intracellular MultiAptamer Genetic Tags" (IMAGEtags). The basic innovation in the proposed IMAGEtag design is the expression in living cells of aptamers that can be used to track the cells in vivo by a noninvasive procedure. Cells that express IMAGEtags will be detected by virtue of the concentrated ligands bound to the aptamers. (End of Abstract)

描述（由申请人提供）： 迄今为止，大多数实时成像程序已用于在体内检测癌细胞。由于几个原因，这些方法的应用可能不适合干细胞。首先，跟踪系统包括在细胞中的表达，以跟踪异物蛋白质，该蛋白具有改变干细胞行为（例如增殖，分化和迁移）的潜力。其次，外国蛋白质的产生通常在细胞中其他蛋白质的水平上达到许多折叠，要求该细胞将大部分能量投入其合成。尽管对于通常表达很高水平的己糖激酶和葡萄糖转运蛋白来通过糖酵解制造ATP的癌细胞不太可能是一个问题，但干细胞的稳健性较低，可能会衰弱。为了有效的组织修复，干细胞必须在先前受损的组织的区域中迁移和增殖，而这些组织通常是缺氧和营养耗尽的。 从本构启动子中合成异物蛋白质的另外需求无法轻易地调节，当需要应对环境不足并可能减少可以成功填充受损组织的细胞数量时，会给细胞带来能源负担。因此，对于标记干细胞，拥有一个不会在正在成像的细胞上施加巨大能源负担的系统将是很大的优势。 这里提出的研究的最终目标是开发一种标记干细胞的无害手段，以便可以在体内和实时跟踪它们，而不会通过标记系统改变其归因，增殖和分化的潜力。当前的建议描述了一种新型的核酸结构，该结构将在细胞中表达以标记它们，以便可以通过可用的成像技术在体内跟踪它们。我们称标记为“细胞内多培养基遗传标签”（图像图）。所提出的成像标签设计中的基本创新是适体的活细胞中的表达，可用于通过非侵入性程序在体内跟踪细胞。将通过与适体结合的浓缩配体检测到表达成像塔的细胞。 （抽象的结尾）