Institute for Stem Cell and Regenerative Medicine, University of Washington, 850 Republican Street, Brotman Building Room 453, Seattle, WA 98109, USA; Center for Cardiovascular Biology, University of Washington, Seattle, WA 98109, USA; Department of Laboratory Medicine & Pathology, University of Washington, Seattle, WA 98195, USA.
Institute for Stem Cell and Regenerative Medicine, University of Washington, 850 Republican Street, Brotman Building Room 453, Seattle, WA 98109, USA; Center for Cardiovascular Biology, University of Washington, Seattle, WA 98109, USA; Division of Cardiology, Department of Medicine, University of Washington, Seattle, WA 98195, USA.
Cell Stem Cell. 2023 Apr 6;30(4):396-414.e9. doi: 10.1016/j.stem.2023.03.010.
Human pluripotent stem cell-derived cardiomyocytes (hPSC-CMs) offer a promising cell-based therapy for myocardial infarction. However, the presence of transitory ventricular arrhythmias, termed engraftment arrhythmias (EAs), hampers clinical applications. We hypothesized that EA results from pacemaker-like activity of hPSC-CMs associated with their developmental immaturity. We characterized ion channel expression patterns during maturation of transplanted hPSC-CMs and used pharmacology and genome editing to identify those responsible for automaticity in vitro. Multiple engineered cell lines were then transplanted in vivo into uninjured porcine hearts. Abolishing depolarization-associated genes HCN4, CACNA1H, and SLC8A1, along with overexpressing hyperpolarization-associated KCNJ2, creates hPSC-CMs that lack automaticity but contract when externally stimulated. When transplanted in vivo, these cells engrafted and coupled electromechanically with host cardiomyocytes without causing sustained EAs. This study supports the hypothesis that the immature electrophysiological prolife of hPSC-CMs mechanistically underlies EA. Thus, targeting automaticity should improve the safety profile of hPSC-CMs for cardiac remuscularization.
人多能干细胞衍生的心肌细胞（hPSC-CMs）为心肌梗死的细胞治疗提供了一种很有前途的方法。然而，短暂性室性心律失常的存在，即所谓的植入性心律失常（EAs），阻碍了其临床应用。我们假设 EA 是由与 hPSC-CMs 发育不成熟相关的起搏器样活动引起的。我们在移植的 hPSC-CMs 成熟过程中对离子通道表达模式进行了特征描述，并使用药理学和基因组编辑来鉴定那些在体外引起自发性的离子通道。然后，将多个工程细胞系移植到未受损的猪心脏中。敲除与去极化相关的基因 HCN4、CACNA1H 和 SLC8A1，同时过表达超极化相关的 KCNJ2，可产生缺乏自发性但可在外部刺激时收缩的 hPSC-CMs。当体内移植时，这些细胞与宿主心肌细胞发生电偶联并发生植入，而不会引起持续的 EA。这项研究支持这样一种假设，即 hPSC-CMs 不成熟的电生理特性是 EA 的机械基础。因此，靶向自发性应该会提高 hPSC-CMs 用于心脏再肌化的安全性。
