Exosome-mediated cardioprotection and regeneration

外泌体介导的心脏保护和再生

• 批准号: 8890879
• 负责人: EDUARDO MARBAN
• 金额: $ 41.86万
• 依托单位: CEDARS-SINAI MEDICAL CENTER
• 依托单位国家: 美国
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-07-11 至 2018-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8890879
• 关键词: Accounting; Acute; Acute myocardial infarction; Allogenic; Animal Model; Anti-Inflammatory Agents; Anti-inflammatory; Antibodies; Apoptosis; Apoptotic; Attenuated; Autologous; Biological Process; Biological Products; Cardiac Myocytes; Cell Therapy; Cell Transplantation; Cell physiology; Cells; Centers for Disease Control and Prevention (U.S.); Cessation of life; Cicatrix; Complement; Data; Dermal; Development; Disease model; Engineering; Fibroblasts; Fibrosis; Goals; Health; Heart; Human; Image; Inflammation; Inflammatory; Injection of therapeutic agent; Intravenous; Knock-out; Left Ventricular Remodeling; Life; Lipid Bilayers; Mass Spectrum Analysis; Mediating; Methods; MicroRNAs; Modeling; Molecular; Mus; Muscle Cells; Myocardial Infarction; Myocardium; Myosin Light Chains; Natural regeneration; Neoplasm Metastasis; Outcome; Pathway interactions; Patients; Proteins; RNA; Recovery of Function; Relative (related person); Resolution; Stem cells; Surface; Testing; Therapeutic; Therapeutic Agents; Therapeutic Effect; Tissue Viability; Transgenic Mice; Transplantation; Vesicle; Work; angiogenesis; base; cardiac regeneration; cardiac repair; cell type; cytokine; heart cell; improved; in vitro activity; in vivo; injured; insight; nanosized; novel; pre-clinical; relating to nervous system; targeted delivery; tissue regeneration; trafficking; tumor

DESCRIPTION (provided by applicant): Cardiosphere-derived cells (CDCs) are effective in reducing scar size and regenerating viable myocardium in patients after myocardial infarction (MI), and exert acute cardioprotective effects in animal models of MI. The major benefits of CDCs appear to be mediated by indirect mechanisms. Here we test the overarching hypothesis that the indirect effects of CDCs are mediated by exosomes. Secreted by a wide range of cell types, exosomes are 30-100 nm lipid bilayer vesicles that are enriched in RNAs including microRNAs (miRs). Our preliminary data indicate that exosomes secreted by human CDCs reproduce the therapeutic benefits of CDCs, and are indispensable for the therapeutic benefits of CDCs, in a mouse acute MI model. Injection of CDC-exosomes into the injured heart mimics the structural and functional benefits of CDC transplantation; conversely, inhibition of exosome secretion by CDCs abrogates the therapeutic benefits of transplanted CDCs. Not all exosomes are salutary: Injection of exosomes from dermal fibroblasts, control cells which do not improve post-MI outcomes, had no therapeutic benefit. CDC-exosomes decreased acute cardiomyocyte death and inflammatory cytokine release, while attenuating LV remodeling and fibrosis in the post-MI heart. Preliminary data from microRNA arrays reveal several "signature miRs" that are highly up-regulated in CDC- exosomes. In contrast, mass spectrometry indicates that the protein composition of CDC-exosomes is conventional and comparable to that of fibroblast-exosomes. Thus, we hypothesize that: i) CDC-exosomes contain a unique complement of miRs that, collectively, mediate many, or all, of the therapeutic effects of CDCs; ii) CDC-exosomes and their constituent miRs favorably modulate apoptosis, inflammation and fibrosis in the post-MI heart; iii) CDC-exosomes improve functional recovery and increase tissue viability post-MI; iv) CDC-exosomes represent a viable "cell free" therapeutic candidate for cardiac repair. Here we propose to sequence the full RNA content of CDC-exosomes, to determine the molecular basis underlying the therapeutic benefit of CDC-exosomes, and to optimize delivery strategies in vivo. Our ultimate goal is to develop CDC-exosomes as a biologic product to treat MI and HF. Because exosomes are unlike live cells that can migrate actively towards a target, we also seek to test novel delivery methods to target CDC-exosomes selectively to injured myocytes. The proposal is both hypothesis-driven and product-oriented. We seek to answer both mechanistic and translational questions in detail, relying upon state-of-the-art scientific methods and well-established preclinical disease models. CDCs (both autologous and allogeneic) are already in human trials, but cells have their limitations as therapeutic agents. Thus, our proposal, focusing on CDC-exosomes (as cell-free derivatives of CDCs), is of potentially significant translational value. The results will also open up novel insights into the fundamental mechanisms of cell-mediated cardioprotection and cardiac regeneration after acute MI.

描述（由申请人提供）：心肌球衍生细胞（CDC）可有效减少心肌梗塞（MI）患者的疤痕大小并再生存活的心肌，并在 MI 动物模型中发挥急性心脏保护作用。 CDC 的主要好处似乎是通过间接机制实现的。在这里，我们测试了一个总体假设，即 CDC 的间接作用是由外泌体介导的。外泌体由多种细胞类型分泌，是一种 30-100 nm 的脂质双层囊泡，富含 RNA，包括 microRNA (miR)。我们的初步数据表明，人类 CDC 分泌的外泌体再现了 CDC 的治疗效果，并且在小鼠急性 MI 模型中对于 CDC 的治疗效果是不可或缺的。将 CDC-外泌体注射到受伤的心脏中模拟了 CDC 移植的结构和功能益处；相反，CDC 抑制外泌体分泌会消除移植 CDC 的治疗效果。并非所有外泌体都是有益的：注射来自真皮成纤维细胞（对照细胞）的外泌体不会改善心肌梗死后的结果，没有治疗益处。 CDC-外泌体减少了急性心肌细胞死亡和炎症细胞因子的释放，同时减轻了心肌梗死后心脏的左室重塑和纤维化。来自 microRNA 阵列的初步数据揭示了几种在 CDC 外泌体中高度上调的“特征 miR”。相反，质谱分析表明CDC-外泌体的蛋白质组成是常规的并且与成纤维细胞外泌体的蛋白质组成相当。因此，我们假设： i) CDC-外泌体含有独特的 miR 补体，它们共同介导 CDC 的许多或全部治疗效果； ii) CDC-外泌体及其组成的 miR 有利于调节 MI 后心脏的细胞凋亡、炎症和纤维化； iii) CDC-外泌体改善功能恢复并增加心肌梗死后的组织活力； iv) CDC-外泌体代表了心脏修复的可行的“无细胞”治疗候选物。在这里，我们建议对 CDC-外泌体的完整 RNA 含量进行测序，以确定 CDC-外泌体治疗益处的分子基础，并优化体内递送策略。我们的最终目标是开发 CDC-外泌体作为治疗 MI 和 HF 的生物产品。由于外泌体与可以主动向目标迁移的活细胞不同，我们还寻求测试新的递送方法，以选择性地将 CDC-外泌体靶向受损的肌细胞。该提案既以假设为驱动，又以产品为导向。我们寻求依靠最先进的科学方法和完善的临床前疾病模型来详细回答机械和转化问题。 CDC（自体和同种异体）已经进入人体试验，但细胞作为治疗剂有其局限性。因此，我们的建议侧重于 CDC 外泌体（作为 CDC 的无细胞衍生物），具有潜在的重大转化价值。这些结果还将为急性心肌梗死后细胞介导的心脏保护和心脏再生的基本机制开辟新的见解。