Syncytium cell growth increases Kir2.1 contribution in human iPSC-cardiomyocytes.
Syncytium cell growth increases Kir2.1 contribution in human iPSC-cardiomyocytes.
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DOI：
10.1152/ajpheart.00148.2020
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发表时间：
2020-11-01
期刊：
影响因子：
--
通讯作者：
Entcheva E
中科院分区：
文献类型：
--
作者：
Li W;Han JL;Entcheva E
人类诱导多能干细胞来源的心肌细胞 (hiPSC-CM) 可实现心脏毒性测试和个性化医疗。然而，它们的成熟度值得关注，包括与成年心肌细胞相比相对去极化的静息膜电位和更多的自发活动，这意味着内向整流钾电流（Ik1）较低或缺乏。在这里，蛋白质定量证实了 hiPSC-CM 合胞体中的 Kir2.1 表达，尽管比成人心脏组织中的表达低几倍。我们发现 hiPSC-CM 培养密度在 mRNA 水平（钾内向整流通道亚家族 J 成员 2）和蛋白质水平及其相关的电生理学表型上影响 Kir2.1 表达。也就是说，全光学心脏电生理学和药物治疗揭示了在致密培养物中自发和不规则活动的减少以及动作电位上冲的增加。仅在最高密度的培养物中，用 BaCl2 阻断类似 Ik1 的电流会增加自发频率，并以剂量依赖性方式减弱起搏期间动作电位的上冲，这与 Ik1 在调节静息膜电位中的作用一致。我们的结果强调了 hiPSC-CM 合胞体生长对于更多生理相关表型的重要性，以及全光学电生理学在多细胞环境中研究心肌细胞的能力。新的和值得注意的我们确定细胞培养密度和细胞-细胞接触是决定转录和蛋白质水平上关键离子通道 KCNJ2/Kir2.1 表达的重要因素，及其对人类诱导多能干细胞来源的心肌细胞电生理学的贡献。我们的结果表明，对脱离组织背景的分离细胞的研究可能会低估所表征的细胞离子通道特性。
Human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) enable cardiotoxicity testing and personalized medicine. However, their maturity is of concern, including relatively depolarized resting membrane potential and more spontaneous activity compared with adult cardiomyocytes, implicating low or lacking inward rectifier potassium current (Ik1). Here, protein quantification confirms Kir2.1 expression in hiPSC-CM syncytia, albeit several times lower than in adult heart tissue. We find that hiPSC-CM culture density influences Kir2.1 expression at the mRNA level (potassium inwardly rectifying channel subfamily J member 2) and at the protein level and its associated electrophysiology phenotype. Namely, all-optical cardiac electrophysiology and pharmacological treatments reveal reduction of spontaneous and irregular activity and increase in action potential upstroke in denser cultures. Blocking Ik1-like currents with BaCl2 increased spontaneous frequency and blunted action potential upstrokes during pacing in a dose-dependent manner only in the highest-density cultures, in line with Ik1’s role in regulating the resting membrane potential. Our results emphasize the importance of syncytial growth of hiPSC-CMs for more physiologically relevant phenotype and the power of all-optical electrophysiology to study cardiomyocytes in their multicellular setting. NEW & NOTEWORTHY We identify cell culture density and cell-cell contact as an important factor in determining the expression of a key ion channel at the transcriptional and the protein levels, KCNJ2/Kir2.1, and its contribution to the electrophysiology of human induced pluripotent stem cell-derived cardiomyocytes. Our results indicate that studies on isolated cells, out of tissue context, may underestimate the cellular ion channel properties being characterized.
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影响因子：
5
作者：
Kim, Jong J.;Yang, Lei;Lin, Bo;Zhu, Xiaodong;Sun, Bin;Kaplan, Aaron D.;Bett, Glenna C. L.;Rasmusson, Randall L.;London, Barry;Salama, Guy
通讯作者：
Salama, Guy
影响因子：
5.5
作者：
Bett, Glenna C. L.;Kaplan, Aaron D.;Lis, Agnieszka;Cimato, Thomas R.;Tzanakakis, Emmanuel S.;Zhou, Qinlian;Morales, Michael J.;Rasmusson, Randall L.
通讯作者：
Rasmusson, Randall L.
光能作为高通量全光动态心脏电生理学的自动化系统。
影响因子：
16.6
作者：
Klimas A;Ambrosi CM;Yu J;Williams JC;Bien H;Entcheva E
通讯作者：
Entcheva E
DOI：
10.1113/jp271559
发表时间：
2016-05-01
期刊：
The Journal of physiology
影响因子：
--
作者：
Entcheva E;Bub G
通讯作者：
Bub G
影响因子：
20.1
作者：
Abriel H;Rougier JS;Jalife J
通讯作者：
Jalife J