Dual Modality Labels for Macro and Micro Detection and Quantification of Stem Cel

用于干细胞宏观和微观检测及定量的双模态标签

• 批准号: 7909750
• 负责人: Brian David Gray
• 金额: $ 19.62万
• 依托单位: MOLECULAR TARGETING TECHNOLOGIES, INC.
• 依托单位国家: 美国
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-07-15 至 2012-04-14
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7909750
• 关键词: Affect; Alzheimer' s Disease; Animal Model; Animals; Autoradiography; Binding; Biodistribution; Biological Process; Carbocyanines; Cell Differentiation process; Cell Survival; Cell Therapy; Cell membrane; Cell physiology; Cells; Chelating Agents; Chemicals; Clinical; Clinical Research; Clinical Trials; Controlled Study; Data; Detection; Development; Diabetes Mellitus; Disadvantaged; Disease; Dyes; Engraftment; Evaluation; Family; Fluorescence; Fluorochrome; Future; Generations; Half-Life; Hand; Heart Diseases; High Pressure Liquid Chromatography; Histologic; Histology; Homing; Hydrocarbons; Image; In Vitro; Indium; Indium-111; Individual; Ischemia; Knowledge; Label; Lead; Location; Measurement; Medicine; Membrane; Methods; Microscopic; Microscopy; Modality; Molecular; Monitor; Mus; Noise; Nuclear; Organ; Oxyquinoline; PKH 26; PKH67; Parkinson Disease; Pentetic Acid; Phase; Physiological; Positron-Emission Tomography; Property; Radio; Radioactivity; Radioisotopes; Radiolabeled; Reagent; Reference Standards; Research; Resolution; Signal Transduction; Site; Solubility; Spinal cord injury; Stem cells; Stroke; System; Tail; Time; Tissue Sample; Tissues; Toxic effect; Tracer; Transplantation; Tropolone; analog; cell type; commercialization; cytotoxicity; daughter cell; embryonic stem cell; fluorophore; imaging modality; imaging probe; improved; in vitro Assay; in vivo; insight; interest; killings; meetings; migration; next generation; optical imaging; public health relevance; radiation effect; radiochemical; radiotracer; safety study; single photon emission computed tomography; stem; stem cell biology; stem cell differentiation; stem cell therapy; tool; uptake

DESCRIPTION (provided by applicant): Stem cells hold promise for treatment of a number of disease states such as Parkinson's, Alzheimer's, spinal cord injury, diabetes, ischemia stroke and heart disease since stem cells have the potential under certain physiological conditions to develop into many different specialized cell types with individual functions. There are 2,620 clinical trials involving stem cells that are either on-going or have been completed, however, to-date, no stem cell therapy has received full FDA approval. The potential that stem cells offer remains to be better understood by observing their fate in vivo (e.g. bio-distribution, survival and differentiation) and this requires the means by which to track the cells non-invasively overtime. Methods are available to visualize cells, each having its own advantages and disadvantages, however, at present, no single imaging modality possess all the desired qualities for optimal evaluation of stem cell therapies. Likewise, many currently available direct cell labels have limitations due to cell toxicity, intracellular radiation effects, inefficient uptake and most importantly, rapid elution from the cell. We hypothesize that dual-modality imaging of stem cells using a non-diffusable dual-labeled imaging probe consisting of a far-red fluorophore and a radionuclide can provide complementary information regarding stem cell location longitudinally, thereby providing an accurate global picture of stem cell biodistribution in vivo which may lead to an improved understanding of stem cell biology and guide emerging stem cell therapies. In Phase I, MTTI will synthesize a dual modality probe for stem cell labeling comprising of three components: (i) a chelator (DTPA) for radiolabeling with 111In allowing detection by SPECT; (ii) a far red emitting fluorochrome to permit observation by optical imaging at the macro and micro-levels, and (iii) long hydrocarbon tails to provide stable non-diffusable incorporation of the probe into the plasma membrane. The probe's cytotoxicity, radiotoxicity, signal:noise, membrane retention and effect on various mouse stem cell functions will be characterized using standard in vitro assays. We expect to establish a suitable probe concentration which does not alter cell viability, proliferation or differentiation, and show that the probe is passed on to the next generation of daughter cells; but does not get incorporated into neighboring cells. Finally, utility of the probe to quantify and track stem cell distribution in vivo in a normal mouse using small animal SPECT and optical imaging systems will be evaluated. The fluorochrome present will also permit microscopic evaluation of tissue samples of interest after sacrifice. We expect to demonstrate that stem cells with the dual labeled marker will localize and accumulate in our animal model in a manner consistent with the cell type and be "visible" for several cell generations. Phase II will include studies in larger animal models, synthesis and evaluation of a dual modality probe for PET and optical imaging, commercialization of the dual probes as research tools and initiation of assembly of a data package for eventual clinical use. PUBLIC HEALTH RELEVANCE: Stem cells hold promise for the treatment of a number of disease states such as Parkinson's, Alzheimer's, spinal cord injury, diabetes, ischemia stroke and heart disease, but their true potential remains to be better understood by observing their fate in vivo. We propose to develop a dual modality label for stem cell tracking using nuclear and optical imaging modalities. This label is expected to provide a highly sensitive and accurate global picture of stem cell biodistribution longitudinally, which may lead to an improved understanding of stem cell biology, and in the future guide emerging stem cell therapies.

描述（由申请人提供）：干细胞有望治疗多种疾病，如帕金森病、阿尔茨海默病、脊髓损伤、糖尿病、缺血性中风和心脏病，因为干细胞在某些生理条件下有潜力发育成许多不同的具有各自功能的专门细胞类型。目前有 2,620 项涉及干细胞的临床试验正在进行或已经完成，但迄今为止，还没有干细胞疗法获得 FDA 的完全批准。干细胞提供的潜力仍有待通过观察它们在体内的命运（例如生物分布、存活和分化）来更好地理解，这需要一种非侵入性地长期跟踪细胞的方法。有多种方法可以使细胞可视化，每种方法都有其自身的优点和缺点，然而，目前没有一种单一的成像方式具备最佳评估干细胞疗法所需的所有品质。同样，许多目前可用的直接细胞标记由于细胞毒性、细胞内辐射效应、低效吸收以及最重要的是从细胞中快速洗脱而具有局限性。我们假设使用由远红荧光团和放射性核素组成的非扩散双标记成像探针对干细胞进行双模态成像可以提供有关干细胞纵向位置的补充信息，从而提供体内干细胞生物分布的准确全局图像，这可能会提高对干细胞生物学的理解并指导新兴的干细胞治疗。在第一阶段，MTTI 将合成用于干细胞标记的双模态探针，其中包含三个组件：（i）用于用 111In 进行放射性标记的螯合剂（DTPA），允许通过 SPECT 进行检测； (ii) 发射远红光的荧光染料，以允许在宏观和微观水平上通过光学成像进行观察，以及 (iii) 长碳氢化合物尾部，以将探针稳定地非扩散地掺入质膜中。将使用标准体外测定来表征探针的细胞毒性、放射毒性、信号：噪声、膜保留以及对各种小鼠干细胞功能的影响。我们期望建立一个合适的探针浓度，该浓度不会改变细胞活力、增殖或分化，并表明探针可以传递到下一代子细胞；但不会并入相邻细胞。最后，将评估探针使用小动物 SPECT 和光学成像系统量化和跟踪正常小鼠体内干细胞分布的效用。存在的荧光染料还允许在处死后对感兴趣的组织样本进行显微镜评估。我们期望证明具有双标记标记的干细胞将以与细胞类型一致的方式在我们的动物模型中定位和积累，并且在多个细胞代中“可见”。第二阶段将包括对较大动物模型的研究、用于 PET 和光学成像的双模态探针的合成和评估、双探针作为研究工具的商业化以及启动数据包的组装以供最终临床使用。 公共健康相关性：干细胞有望治疗帕金森氏症、阿尔茨海默氏症、脊髓损伤、糖尿病、缺血性中风和心脏病等多种疾病，但它们的真正潜力仍有待通过观察它们在体内的命运来更好地了解。我们建议使用核成像和光学成像方式开发用于干细胞追踪的双模态标签。该标签有望提供干细胞纵向生物分布的高度敏感和准确的全局图，这可能会提高对干细胞生物学的理解，并在未来指导新兴的干细胞疗法。