Department of Anatomy and Embryology, Leiden University Medical Center, Einthovenweg, Leiden, The Netherlands.
Department of Applied Stem Cell Technologies, TechMed Centre, University of Twente, Enschede, The Netherlands.
Cardiovasc Res. 2020 Mar 1;116(3):545-553. doi: 10.1093/cvr/cvz181.
Cardiovascular diseases caused by loss of functional cardiomyocytes (CMs) are a major cause of mortality and morbidity worldwide due in part to the low regenerative capacity of the adult human heart. Human pluripotent stem cell (hPSC)-derived cardiovascular progenitor cells (CPCs) are a potential cell source for cardiac repair. The aim of this study was to examine the impact of extensive remuscularization and coincident revascularization on cardiac remodelling and function in a mouse model of myocardial infarction (MI) by transplanting doxycycline (DOX)-inducible (Tet-On-MYC) hPSC-derived CPCs in vivo and inducing proliferation and cardiovascular differentiation in a drug-regulated manner.
CPCs were injected firstly at a non-cardiac site in Matrigel suspension under the skin of immunocompromised mice to assess their commitment to the cardiovascular lineage and ability to self-renew or differentiate in vivo when instructed by systemically delivered factors including DOX and basic fibroblast growth factor (bFGF). CPCs in Matrigel were then injected intra-myocardially in mice subjected to MI to assess whether expandable CPCs could mediate cardiac repair. Transplanted CPCs expanded robustly both subcutis and in the myocardium using the same DOX/growth factor inducing regime. Upon withdrawal of these cell-renewal factors, CPCs differentiated with high efficiency at both sites into the major cardiac lineages including CMs, endothelial cells, and smooth muscle cells. After MI, engraftment of CPCs in the heart significantly reduced fibrosis in the infarcted area and prevented left ventricular remodelling, although cardiac function determined by magnetic resonance imaging was unaltered.
Replacement of large areas of muscle may be required to regenerate the heart of patients following MI. Our human/mouse model demonstrated that proliferating hPSC-CPCs could reduce infarct size and fibrosis resulting in formation of large grafts. Importantly, the results suggested that expanding transplanted cells in situ at the progenitor stage maybe be an effective alternative causing less tissue damage than injection of very large numbers of CMs.
由于功能性心肌细胞 (CM) 的丧失导致的心血管疾病是全球范围内死亡和发病的主要原因，部分原因是成人心脏的再生能力低。人多能干细胞 (hPSC) 衍生的心血管祖细胞 (CPC) 是心脏修复的潜在细胞来源。本研究的目的是通过体内移植可诱导多西环素 (DOX) (Tet-On-MYC) hPSC 衍生 CPC，并以药物调节的方式诱导增殖和心血管分化，研究在心肌梗死 (MI) 小鼠模型中广泛再肌化和伴随的再血管化对心脏重塑和功能的影响。
首先，将 CPC 在 Matrigel 悬浮液中注射到免疫缺陷小鼠的非心脏部位的皮下，以评估它们在包括 DOX 和碱性成纤维细胞生长因子 (bFGF) 等系统给予的因子的指导下向心血管谱系的定向能力，以及体内自我更新或分化的能力。然后，将 CPC 在 Matrigel 中注射到 MI 小鼠的心肌内，以评估可扩展的 CPC 是否可以介导心脏修复。使用相同的 DOX/生长因子诱导方案，在皮下和心肌中，CPC 都大量扩增。在撤出这些细胞更新因子后，CPC 在这两个部位高效分化为包括心肌细胞、内皮细胞和平滑肌细胞在内的主要心脏谱系。在 MI 后，CPC 在心脏中的植入显著减少了梗死区的纤维化并防止了左心室重塑，尽管心脏功能磁共振成像未改变。
在 MI 后，可能需要替换大量的肌肉来再生患者的心脏。我们的人/鼠模型表明，增殖的 hPSC-CPC 可以减少梗死面积和纤维化，从而形成大的移植物。重要的是，结果表明，在祖细胞阶段原位扩增移植细胞可能是一种有效的替代方法，比注射大量的心肌细胞造成的组织损伤更小。
