Enhancing the effectiveness of human cardiac stem cell therapy

描述（由申请人提供）：缺血性心脏病仍然是美国最大的单一死亡原因。移植c-kit阳性的人心脏干细胞（hCSCs）是修复梗死心脏的一种非常有前途的治疗方法，但供体细胞的存活率很低，严重限制了这种方法的应用。一氧化碳（CO）是血红素加氧酶1 （HO-1）的副产物，对心肌细胞缺血/再灌注损伤具有有效的抗凋亡和细胞保护作用。然而，HO-1/CO是否对hscs具有细胞保护作用尚不清楚。我们的前期研究发现，HO-1/CO在介导hCSC存活能力中起重要作用。因此，本研究的重点是验证我们的假设，即HO-1/CO通过激活生存信号通路和细胞因子作用促进人类心脏干细胞存活，并提高心肌梗死后免疫缺陷小鼠心脏移植后干细胞的治疗效果和心脏功能。因此，我们将研究用HO-1诱导剂（CoPP）或CO释放分子（CORM-3）预处理的hCSC是否会在细胞存活、增殖、迁移、内皮和心肌分化（目的1）方面表现出更强的能力，并了解HO-1/CO对hCSC存活信号通路、细胞凋亡抗性、ROS生成和细胞因子释放的影响的分子机制（目的2）。本课题的目的3将通过免疫缺陷小鼠（SCID）模型，测试预处理eGFP+-hCSCs移植是否会改善心肌梗死后体内hCSC的存活和归巢、内源性小鼠CSC的增殖和分化以及心脏结构和功能。从上述实验中获得的知识将为提高移植后hCSC存活的策略提供重要意义，从而为缺血性心脏病患者的细胞治疗提供临床修复梗死心肌的功效。

DESCRIPTION (provided by applicant): Ischemic heart disease remains as the single largest cause of mortality in the United States. Delivery of c-kit positive human cardiac stem cells (hCSCs) is a very promising therapeutic approach in repairing the infarcted heart, but is severely limited by the poor survival of donor cells. Carbon monoxide (CO), a byproduct of heme oxygenase 1 (HO-1), has a potent anti- apoptotic, cytoprotective effect against ischemia/reperfusion injury to cardiomyocytes. However, it is not known whether HO-1/CO is cytoprotective for hCSCs. Our pilot studies found that HO-1/CO plays an important role in mediating hCSC survival ability. Therefore, this application focuses on testing our hypothesis that HO-1/CO promotes human cardiac stem cell survival vial the activation of survival signal pathways and the cytokine effects, as well as enhances the stem cell therapy efficacy and heart function after transplantation into immunodeficient mouse heart following myocardial infarction. Thus, we will examine whether hCSCs pretreated with an HO-1 inducer (CoPP), or a CO releasing molecule (CORM-3), will exhibit greater abilities in cell survival, proliferation, migration, endothelial and cardiomyogenic differentiation (Aim 1), and understand the molecular mechanisms that underlie the effect of HO-1/CO on hCSC survival signal pathways, resistance to apoptosis, ROS generation and cytokine release (Aim 2). Aim 3 of this proposal will test whether transplantation of the preconditioned eGFP+-hCSCs will result in improvement in invivo hCSC survival and homing, endogenous mouse CSC proliferation and differentiation, and cardiac structure and function with immunodeficient mouse (SCID) model following myocardial infarction. Knowledge gained from the above experiments will provide the essential implications on the strategies to enhance hCSC survival after transplantation and, therefore, their efficacy in clinical repairing infarcted myocardium for the cell therapy of patients with ischemic heart disease.