The immaturity of human induced pluripotent stem cell derived engineered cardiac tissues limits their ability to regenerate damaged myocardium and to serve as robust in vitro models for human disease and drug toxicity studies. Several chronic biomimetic conditioning protocols, including mechanical stretch, perfusion, and/or electrical stimulation promote engineered cardiac tissue maturation but have significant technical limitations. Non-contacting chronic optical stimulation using heterologously expressed channelrhodopsin light-gated ion channels, termed optogenetics, may be an advantageous alternative to chronic invasive electrical stimulation for engineered cardiac tissue conditioning. We designed proof-of-principle experiments to successfully transfect human induced pluripotent stem cell derived engineered cardiac tissues with a desensitization resistant, chimeric channelrhodopsin protein, and then optically paced engineered cardiac tissues to accelerate maturation. We transfected human induced pluripotent stem cell engineered cardiac tissues using an adeno-associated virus packaged chimeric channelrhodopsin and then verified optically paced by whole cell patch clamp. Engineered cardiac tissues were then chronically optically paced above their intrinsic beat rates in vitro from day 7 to 14. Chronically optically paced resulted in improved engineered cardiac tissue electrophysiological properties and subtle changes in the expression of some cardiac relevant genes, though active force generation and histology were unchanged. These results validate the feasibility of a novel chronically optically paced paradigm to explore non-invasive and scalable optically paced-induced engineered cardiac tissue maturation strategies.

中文翻译：

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h-iPSC工程心脏组织的慢性光学起搏条件。

人类诱导的多能干细胞衍生的工程心脏组织的不成熟限制了它们再生受损心肌的能力，并不能用作人类疾病和药物毒性研究的可靠体外模型。包括机械拉伸，灌注和/或电刺激在内的几种慢性仿生调节方案可促进工程心脏组织的成熟，但具有明显的技术局限性。使用异源表达的视紫红质光门控离子通道的非接触式慢性光刺激，称为光遗传学，可能是用于工程心脏组织调节的慢性侵入性电刺激的有利替代方法。我们设计了原理验证实验，以抗脱敏的嵌合通道视紫红质蛋白成功转染人诱导的多能干细胞衍生的工程化心脏组织，然后进行光学起搏的工程化心脏组织以加速成熟。我们使用包装了腺相关病毒的嵌合通道视紫红质转染了人类诱导的多能干细胞工程心脏组织，然后通过全细胞膜片钳进行了光学步速验证。然后，从体外培养第7天到第14天，对心脏工程组织进行长期的光学起搏，使其高于其固有的搏动速率。通过长期光学起搏，尽管活动力的产生和组织学改变，工程心脏组织的电生理特性有所改善，一些心脏相关基因的表达也发生了细微变化。没有变化。