Moscow Institute of Physics and Technology, Dolgoprudny, Russian Federation.
Institute of Cytology and Genetics.
Toxicol Sci. 2019 Mar 1;168(1):70-77. doi: 10.1093/toxsci/kfy274.
In vitro screening for potential side effects of drugs on human-induced pluripotent stem-cell-derived cardiomyocytes (hiPSC-CMs) is a cutting-edge technology in pharmaceutical industry. International groups are currently considering using iPSC-CM as a part of comprehensive battery for an accurate and complex mechanistic-based assessment of the proarrhythmic potential of drugs. Despite iPSC-CMs expression and phenotype differences from mature adult CMs screening for drug-induced prolonged QT interval is now routinely carried and also recommended by ICH. The revelation of the mechanism of how the elongation of the QT interval is associated with the occurrence of an arrhythmia should extend the prospects of screening. To address this problem, a comprehensive tissue-based test for arrhythmogenicity is needed. Induced pluripotent stem (iPS) cells from a healthy individual were differentiated into a CM monolayer that was identified by immunocytochemistry and the patch-clamp technique also considering of the potential impact of the developing phenotype of the iPSC-CMs. To study the occurrence of reentry as a precursor to arrhythmias, a standard obstacle was created in the cell layer. With the aid of optical mapping, the measure of arrhythmogenicity was determined, as defined by the probability of a reentry occurrence for the particular frequency of stimulation. A change in the potassium current corresponding to LQTS type 2 at frequencies matching high heart rates was demonstrated visually and quantitatively. Also, the efficiency of this method for quantifying both the effectiveness and ineffectiveness of drugs for a particular donor and for determining the donor's cardiovascular disease risk zone was tested.
在体筛选药物对人诱导多能干细胞衍生心肌细胞（hiPSC-CMs）的潜在副作用是制药行业的一项前沿技术。国际组织目前正在考虑将 iPSC-CM 作为综合电池的一部分，用于准确和复杂的药物致心律失常潜在性的基于机制的评估。尽管 iPSC-CMs 的表达和表型与成熟的成年 CM 不同，但目前已经常规进行药物诱导 QT 间期延长的筛选，ICH 也推荐进行这种筛选。揭示 QT 间期延长与心律失常发生相关的机制应该会扩展筛选的前景。为了解决这个问题，需要进行全面的基于组织的致心律失常性测试。从健康个体中诱导多能（iPS）细胞分化为 CM 单层，通过免疫细胞化学和膜片钳技术进行鉴定，同时考虑到 iPSC-CMs 发育表型的潜在影响。为了研究折返作为心律失常发生的前兆，在细胞层中创建了一个标准障碍物。借助光学映射，根据特定刺激频率的折返发生概率来确定致心律失常性的测量。还直观和定量地证明了在匹配高心率的频率下，对应 LQTS 类型 2 的钾电流发生变化。此外，还测试了这种方法用于量化特定供体的药物有效性和无效性以及确定供体的心血管疾病风险区域的效率。
