Mechanism-Based Facilitated Maturation of Human Pluripotent Stem Cell–Derived Cardiomyocytes

Lieu, Deborah K.; Fu, Ji-Dong; Chiamvimonvat, Nipavan; Tung, Kelvin W. Chan; McNerney, Gregory P.; Huser, Thomas; Keller, Gordon; Kong, Chi-Wing; Tse, Gary

doi:10.1161/circep.111.973420

Cited by 165 publications

(187 citation statements)

References 47 publications

Supporting

Mentioning

174

Contrasting

Order By: Relevance

“…Despite their utility in human arrhythmia models, iPSC-CMs differ from adult tissue-derived cardiomyocytes (29)(30)(31)(32)(33). APs recorded from iPSC-CMs display depolarized diastolic potentials, myogenic AP firing, and a reduced maximum rise rate of the AP upstroke (dV/dt MAX ) compared with APs from adult ventricular tissue (Fig.…”

Section: Discussionmentioning

confidence: 99%

hERG 1b is critical for human cardiac repolarization

Jones¹,

Liu²,

Vaidyanathan

et al. 2014

Proc. Natl. Acad. Sci. U.S.A.

108

View full text Add to dashboard Cite

The human ether-à-go-go-related gene (hERG; or KCNH2) encodes the voltage-gated potassium channel underlying I Kr , a repolarizing current in the heart. Mutations in KCNH2 or pharmacological agents that reduce I Kr slow action potential (AP) repolarization and can trigger cardiac arrhythmias associated with long QT syndrome. Two channel-forming subunits encoded by KCNH2 (hERG 1a and 1b) are expressed in cardiac tissue. In heterologous expression systems, these subunits avidly coassemble and exhibit biophysical and pharmacological properties distinct from those of homomeric hERG 1a channels. Despite these findings, adoption of hERG 1a/1b heteromeric channels as a model for cardiac I Kr has been hampered by the lack of evidence for a direct functional role for the 1b subunit in native tissue. In this study, we measured I Kr and APs at physiological temperature in cardiomyocytes derived from human induced pluripotent stem cells (iPSC-CMs). We found that specific knockdown of the 1b subunit using shRNA caused reductions in 1b mRNA, 1b protein levels, and I Kr magnitude by roughly one-half. AP duration was increased and AP variability was enhanced relative to controls. Early afterdepolarizations, considered cellular substrates for arrhythmia, were also observed in cells with reduced 1b expression. Similar behavior was elicited when channels were effectively converted from heteromers to 1a homomers by expressing a fragment corresponding to the 1a-specific N-terminal Per-Arnt-Sim domain, which is omitted from hERG 1b by alternate transcription. These findings establish that hERG 1b is critical for normal repolarization and that loss of 1b is proarrhythmic in human cardiac cells.T he human ether-à-go-go-related gene (hERG; or KCNH2) encodes the voltage-gated potassium channel underlying a native cardiac current known as I Kr (1, 2). Mutations in the gene or drugs that block the channel can diminish I Kr and slow ventricular repolarization, thus prolonging the QT interval on the surface electrocardiogram and causing long QT syndrome (LQTS) (1-3). Individuals with LQTS have an increased risk for torsades de pointes arrhythmia, syncope, and sudden cardiac death. Since 2005, a cell-based assay expressing the hERG 1a isoform as a proxy for I Kr has been the cornerstone of drug safety screening for new drug development (4). Thus, whether current drug safety assays accurately represent the native channel is of paramount importance.The first studies of heterologously expressed hERG channels described biophysical (1, 2) and pharmacological (2, 5) properties uniquely characteristic of cardiac I Kr . Subsequently, alternate transcripts of KCNH2 in mouse and human heart were shown to encode two subunits: 1a (the original isolate) and 1b (6, 7). In the hERG 1b transcript, an alternate 5′ exon replaces 1a exons 1-5, resulting in a shorter, unique N terminus that lacks a Per-Arnt-Sim (PAS) domain (also known as the ether-à-go-go domain) (8, 9). In heterologous systems, hERG 1b subunits avidly associate with hERG 1a but fail as homomer...

show abstract

Section: Discussionmentioning

confidence: 99%

hERG 1b is critical for human cardiac repolarization

Jones¹,

Liu²,

Vaidyanathan

et al. 2014

Proc. Natl. Acad. Sci. U.S.A.

108

View full text Add to dashboard Cite

show abstract

“…These results suggest that, despite the fact that specific mechanisms involved in HL-1 cell remodeling may differ significantly from those that take place in human chronic AF (7,30), the described in vitro remodeling is a first, although important, step in the study of AF remodeling mechanisms. For example, the recent development of human cardiac myocytes derived from pluripotent stem cells (16,17) may allow the use of in vitro models of human AF in the near future and should serve to extend our study to a more clinically relevant setting.…”

Section: Discussionmentioning

confidence: 99%

Role of atrial tissue remodeling on rotor dynamics: an in vitro study

Climent

Guillem

Fuentes

et al. 2015

American Journal of Physiology-Heart and Circulatory Physiology

View full text Add to dashboard Cite

The objective of this article is to present an in vitro model of atrial cardiac tissue that could serve to study the mechanisms of remodeling related to atrial fibrillation (AF). We analyze the modification on gene expression and modifications on rotor dynamics following tissue remodeling. Atrial murine cells (HL-1 myocytes) were maintained in culture after the spontaneous initiation of AF and analyzed at two time points: 3.1 ± 1.3 and 9.7 ± 0.5 days after AF initiation. The degree of electrophysiological remodeling (i.e., relative gene expression of key ion channels) and structural inhomogeneity was compared between early and late cell culture times both in nonfibrillating and fibrillating cell cultures. In addition, the electrophysiological characteristics of in vitro fibrillation [e.g., density of phase singularities (PS/cm2), dominant frequency, and rotor meandering] analyzed by means of optical mapping were compared with the degree of electrophysiological remodeling. Fibrillating cell cultures showed a differential ion channel gene expression associated with atrial tissue remodeling (i.e., decreased SCN5A, CACN1C, KCND3, and GJA1 and increased KCNJ2) not present in nonfibrillating cell cultures. Also, fibrillatory complexity was increased in late- vs. early stage cultures (1.12 ± 0.14 vs. 0.43 ± 0.19 PS/cm2, P < 0.01), which was associated with changes in the electrical reentrant patterns (i.e., decrease in rotor tip meandering and increase in wavefront curvature). HL-1 cells can reproduce AF features such as electrophysiological remodeling and an increased complexity of the electrophysiological behavior associated with the fibrillation time that resembles those occurring in patients with chronic AF.

show abstract

“…We previously reported using a heterologous expression model (HEK293 cells) that CAV3 LQT9 mutations increase late I Na (I Na-L ) without affecting peak I Na (I Na-P ) density and steady-state activation or inactivation (3,30) and reduced I K1 density by decreasing surface membrane expression of Kir2.1 (28). Other groups have attempted to compensate for the small density of I K1 in iPS-CMs by electronic addition of I K1 or viral infection of Kir2.1 (2,17), but, to date, augmentation of I K1 has not been systematically studied for its effects on AP characteristics, membrane currents, or cardiomyocyte growth. In the present study we 1) quantify the AP characteristics and effects of pacing; 2) define the percentage of I K1 enhancement; 3) demonstrate calcium transients more similar to adult myocytes; 4) quantify increased cell size, capacitance, and DNA synthesis; and 5) model LQT9 with AP prolongation and production of early afterdepolarizations (EADs).…”

mentioning

confidence: 99%

I_K1-enhanced human-induced pluripotent stem cell-derived cardiomyocytes: an improved cardiomyocyte model to investigate inherited arrhythmia syndromes

Vaidyanathan

Markandeya

Kamp

et al. 2016

American Journal of Physiology-Heart and Circulatory Physiology

View full text Add to dashboard Cite

Vaidyanathan R, Markandeya YS, Kamp TJ, Makielski JC, January CT, Eckhardt LL. IK1-enhanced human-induced pluripotent stem cell-derived cardiomyocytes: an improved cardiomyocyte model to investigate inherited arrhythmia syndromes. Am J Physiol Heart Circ Physiol 310: H1611-H1621, 2016. First published April 8, 2016; doi:10.1152/ajpheart.00481.2015.-Currently available induced pluripotent stem cell-derived cardiomyocytes (iPS-CMs) do not ideally model cellular mechanisms of human arrhythmic disease due to lack of a mature action potential (AP) phenotype. In this study, we create and characterize iPS-CMs with an electrically mature AP induced by potassium inward rectifier (IK1) enhancement. The advantages of IK1-enhanced iPS-CMs include the absence of spontaneous beating, stable resting membrane potentials at approximately Ϫ80 mV and capability for electrical pacing. Compared with unenhanced, IK1-enhanced iPS-CMs calcium transient amplitudes were larger (P Ͻ 0.05) with a typical staircase pattern. IK1-enhanced iPS-CMs demonstrated a twofold increase in cell size and membrane capacitance and increased DNA synthesis compared with control iPS-CMs (P Ͻ 0.05). Furthermore, IK1-enhanced iPS-CMs expressing the F97C-CAV3 long QT9 mutation compared with wild-type CAV3 demonstrated an increase in AP duration and late sodium current. I K1-enhanced iPSCMs represent a more mature cardiomyocyte model to study arrhythmia mechanisms. arrhythmia; potassium ion channel; LQTS; iPS-CM NEW & NOTEWORTHY Ik1-enhanced induced pluripotent stem cell-derived cardiomyocytes (iPS-CMs) more closely represent the cell size, structure, multinucleation, electrophysiology, and calcium handling properties of adult human cardiomyocytes. These I K1-enhanced iPS-CMs will permit advanced studies of arrhythmia mechanisms such as rotor and reentry generation in plated iPS-CMs or drug safety testing due to the mature cellular phenotype.INDUCED PLURIPOTENT STEM (iPS) cells have opened new avenues to investigate many human diseases (33). Patient-specific iPSderived cardiomyocytes (iPS-CMs) have been used to investigate inherited arrhythmia syndromes such as long QT syndrome (LQTS) and catecholeminergic polymorphic ventricular tachycardia (9,21,31,34). These proof of concept studies have recapitulated some characteristic features of human disease (8, 23). However, despite advances in differentiation and culturing techniques, currently available iPS-CMs have several features of immature cardiomyocytes, which limit their application for modeling cellular arrhythmia mechanisms and inherited arrhythmic disease. The electrophysiological limitations occur predominately due to action potential (AP) diastolic properties including a relatively depolarized resting membrane potential and spontaneous automaticity due to a small inward rectifier (I K1 ) density and unopposed pacemaker current (I f ) (5, 18). In turn, this results in partial inactivation of ion channels such as the cardiac sodium channel to reduce current (I Na ) amplitude. Automaticity also interferes w...

show abstract

Mechanism-Based Facilitated Maturation of Human Pluripotent Stem Cell–Derived Cardiomyocytes

Cited by 165 publications

References 47 publications

hERG 1b is critical for human cardiac repolarization

hERG 1b is critical for human cardiac repolarization

Role of atrial tissue remodeling on rotor dynamics: an in vitro study

I_K1-enhanced human-induced pluripotent stem cell-derived cardiomyocytes: an improved cardiomyocyte model to investigate inherited arrhythmia syndromes

Contact Info

Product

Resources

About