Utilizing advanced biomedical imaging to determine the role of cardiac stem cells in physiological remodeling of the heart

利用先进的生物医学成像确定心脏干细胞在心脏生理重塑中的作用

• 批准号: 1628801
• 金额: --
• 依托单位: University College London
• 依托单位国家: 英国
• 项目类别: Studentship
• 财政年份: 2015
• 资助国家: 英国
• 起止时间: 2015 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=studentship-1628801
• 关键词: Utilizing; advanced; biomedical; imaging; determine

Strategic Research Priority: World Class BioscienceAbstract Stem-cells have the potential to repair the heart after physiological and pathological stress. Better understanding of stem-cell biology may enhance this process, providing effective treatments for heart-failure. We recently identified endogenous cardiac stem-cells (eCSCs) which are necessary and sufficient for cardiac regeneration in physiological remodeling. This project will use cutting-edge in-vivo biomedical imaging to simultaneously monitor cardiac function and follow the fate of eCSCs tagged with a lineage specific bioluminescent reporter-gene in response to physiological remodeling. This novel in-vivo eCSC lineage-tracing approach has never been undertaken previously and will inform on the critical link between eCSC activation and cardiac regeneration. Project Aim 1: 0-18 monthsDerive an in vivo lineage tracing mouse through stem cell marker driven Cre recombination of luciferaseBioluminescent luciferase can be used to track cells within living mice. Using Cre-Lox recombination technology we will cross existing mouse lines so that luciferase expression is restricted to c-kit and Sca-1 expressing CSCs and their progeny (Vandeputte et al.2014, Neurobiology of Disease). This will provide a powerful model for non-invasive serial monitoring of the fate/expansion of eCSCs in vivo. Aim-2: 0-18 months Advanced biomedical imaging of physiological remodeling following acute injection of isoproterenol A single injection of isoproterenol induces diffuse myocardial damage with a drop out of 8-10% cardiomyocytes, resulting in acute cardiac failure (Takotsubo-like stress cardiomyopathy), which is both structurally and functionally spontaneously reversible within 28 days(1,2). We have shown that c-kit positive eCSCs are responsible for cardiomyocyte renewal in this physiological remodeling(1). Here, we will fully characterize the isoproterenol model using novel MRI, optical and nuclear imaging techniques that serially assess myocardial hypertrophy, edema, contractility, fibrosis, inflammation and cell death. These studies are independent of the outcome of Aim-1 and will be undertaken in tandem using existing transgenic mouse models that allow fate mapping of eCSCs through inducible CRE-lineage tracing by their expression of c-kit (Heger et al.2014.Eur J Immunol), Sca-1 (Uchida et al.2013.Stem Cell Rep) and Wt1 (Chong et al.2011.Cell Stem Cell). Tissue sections from these mice will be analysed at the cellular level for myocardial regeneration and remodeling by immunohistochemistry and confocal microscopy(1). Aim-3: 18-36 monthsAdvanced biomedical imaging of the role of cardiac stem cells in physiological remodelingAims 1 and 2 will be combined allowing simultaneous in vivo lineage tracing of eCSCs using bioluminescence imaging and monitoring of cardiac function using MRI, nuclear and optical imaging after isoproterenol-induced physiological remodeling.

战略研究重点：世界一流的生物科学摘要干细胞具有在生理和病理应激后修复心脏的潜力。更好地理解干细胞生物学可能会增强这一过程，为心力衰竭提供有效的治疗方法。我们最近发现了内源性心脏干细胞（eCSCs），这是必要的和足够的心脏再生的生理重塑。该项目将使用尖端的体内生物医学成像技术，同时监测心脏功能，并跟踪标记有谱系特异性生物发光标记基因的eCSC的命运，以响应生理重塑。这种新的体内eCSC谱系追踪方法以前从未进行过，并将告知eCSC激活和心脏再生之间的关键联系。项目目标1：0 - 18个月通过干细胞标记物驱动的Cre重组获得体内谱系追踪小鼠生物发光荧光素酶可用于追踪活体小鼠内的细胞。使用Cre-Lox重组技术，我们将杂交现有的小鼠品系，使得荧光素酶表达限于表达c-kit和Sca-1的CSC及其后代（Vandeputte等人，2014，Neurobiology of Disease）。这将为体内eCSC的命运/扩增的非侵入性连续监测提供强大的模型。目标二：0 - 18个月急性注射异丙肾上腺素后生理重塑的先进生物医学成像单次注射异丙肾上腺素可诱导弥漫性心肌损伤，导致8 - 10%的心肌细胞脱落，导致急性心力衰竭（Takotsubo样应激性心肌病），其在结构和功能上在28天内自发可逆（1，2）。我们已经表明，c-kit阳性eCSC负责这种生理重塑中的心肌细胞更新（1）。在这里，我们将充分表征异丙肾上腺素模型使用新的MRI，光学和核成像技术，连续评估心肌肥大，水肿，收缩力，纤维化，炎症和细胞死亡。这些研究与Aim-1的结果无关，将使用现有的转基因小鼠模型串联进行，这些模型允许通过c-kit（Heger et al.2014.Eur J Immunol）、Sca-1（Uchida et al.2013.Stem Cell Rep）和Wt1（Chong et al.2011.Cell Stem Cell）的表达通过诱导型CRE-lineage追踪进行eCSC的命运定位。将通过免疫组织化学和共聚焦显微镜在细胞水平分析这些小鼠的组织切片，以了解心肌再生和重塑（1）。 目标三：18 - 36 monthsAdvancedbiomedical imaging of the role of cardiac stem cells in physiological remodelingaims 1 and 2 will be combined allowing simultaneously in vivo lineage tracing of eCSC using bioluminescence imaging and monitoring of cardiac function using MRI，nuclear and optical imaging after isoproprenol induced physiological remodeling.