Inducible Notch improves progenitor cell repair of damaged heart

描述（由申请人提供）：心肌再生治疗目前受限于过继移植细胞的存活和适当的谱系承诺。Notch信号通路作为一种心脏保护干细胞信号通路，在受损心肌中表达，在心脏干细胞的分化和向成体心脏细胞类型的分化中起着核心作用，Notch信号通路在表达水平和时间上都受到严格调控。这项建议的长期目标是通过调节Notch信号来增强细胞治疗，从而增强心肌修复和再生。短期目标是确定优化的Notch信号在心脏修复中的分子机制。控制Notch信号将通过基因工程进入心脏祖细胞，产生可诱导和可逆的激活Notch信号。具体目标将证明：1)在表达干细胞特异性调节的细胞内Notch的转基因小鼠中，心肌修复增加；2)经过工程改造表达诱导Notch的心脏祖细胞在过继转移到梗死心脏时具有增强的再生能力。目标将通过分子生物学设计，结合生化、组织学和功能分析，对小鼠和人类细胞系进行基因工程设计。拟议研究的意义在于获得对干细胞存活和承诺的控制，这两者共同是基于细胞的治疗实施的深刻限制。这种靶向调节Notch活性的策略不仅可以应用于心脏祖细胞，还可以应用于其他类型的干细胞，以促进再生能力并改变治疗性干细胞治疗的模式。

DESCRIPTION (provided by applicant): Myocardial regenerative therapy is currently limited by survival and appropriate lineage commitment of adoptively transferred cells. The Notch pathway has emerged as a cardioprotective stem cell signaling pathway expressed in damaged myocardium that plays a central role in cardiac stem cell specification and differentiation to adult cardiac cell types, with Notch signaling being tightly regulated in both expression level and timing. The long-term goal of this proposal is to enhance myocardial repair and regeneration using regulated Notch signaling to enhance cellular therapy. The short-term goal is to determine molecular mechanism(s) underlying optimized Notch signaling in cardiac repair. Controlled Notch signaling will be genetically engineered into cardiac progenitor cells to produce activated Notch signaling that is both inducible and reversible. Specific aims will demonstrate: 1) Myocardial repair is increased in transgenic mice expressing stem cell-specific regulated intracellular Notch and 2) Cardiac progenitor cells engineered to express inducible Notch possess augmented regenerative capacity when adoptively transferred to infarcted hearts. Aims will be accomplished by molecular biological design to genetically engineer mouse and human cell lines in combination with biochemical, histological, and functional analyses. The significance of the proposed studies is to gain control over stem cell survival and commitment that together are profound limitations of cell-based therapeutic implementation. This targeted strategy for regulating Notch activity could be applied not only to cardiac progenitor cells but also to other stem cell types in order to promote regenerative capacity and change the paradigm for therapeutic stem cell treatment. PUBLIC HEALTH RELEVANCE: Heart disease persists as the leading cause of morbidity and mortality in the United States and throughout the world. Recent promise of cell-based therapy for treatment of cardiomyopathic injury has been stymied by limited survival, engraftment and persistence of the donated cells. Improving the reparative capacity of adoptively transferred cardiac progenitors remains a significant hurdle to therapeutic implementation. This proposal advances cardiac cell therapy through development of genetically engineered cardiac progenitors cells with enhanced properties to potentiate myocardial regeneration.