Model for long QT syndrome type 2 using human iPS cells demonstrates arrhythmogenic characteristics in cell culture

SUMMARY Long QT syndrome (LQTS) is caused by functional alterations in cardiac ion channels and is associated with prolonged cardiac repolarization time and increased risk of ventricular arrhythmias. Inherited type 2 LQTS (LQT2) and drug-induced LQTS both result from altered function of the hERG channel. We investigated whether the electrophysiological characteristics of LQT2 can be recapitulated in vitro using induced pluripotent stem cell (iPSC) technology. Spontaneously beating cardiomyocytes were differentiated from two iPSC lines derived from an individual with LQT2 carrying the R176W mutation in the KCNH2 (HERG) gene. The individual had been asymptomatic except for occasional palpitations, but his sister and father had died suddenly at an early age. Electrophysiological properties of LQT2-specific cardiomyocytes were studied using microelectrode array and patch-clamp, and were compared with those of cardiomyocytes derived from control cells. The action potential duration of LQT2-specific cardiomyocytes was significantly longer than that of control cardiomyocytes, and the rapid delayed potassium channel (IKr) density of the LQT2 cardiomyocytes was significantly reduced. Additionally, LQT2-derived cardiac cells were more sensitive than controls to potentially arrhythmogenic drugs, including sotalol, and demonstrated arrhythmogenic electrical activity. Consistent with clinical observations, the LQT2 cardiomyocytes demonstrated a more pronounced inverse correlation between the beating rate and repolarization time compared with control cells. Prolonged action potential is present in LQT2-specific cardiomyocytes derived from a mutation carrier and arrhythmias can be triggered by a commonly used drug. Thus, the iPSC-derived, disease-specific cardiomyocytes could serve as an important platform to study pathophysiological mechanisms and drug sensitivity in LQT2.

[1]  Jules C Hancox,et al.  The hERG potassium channel and hERG screening for drug-induced torsades de pointes. , 2008, Pharmacology & therapeutics.

[2]  L. Schild,et al.  Molecular characterization of two founder mutations causing long QT syndrome and identification of compound heterozygous patients , 2006, Annals of medicine.

[3]  Lior Gepstein,et al.  Modelling the long QT syndrome with induced pluripotent stem cells , 2011, Nature.

[4]  A. C. Fijnvandraat.  Embryonic stem cell-derived cardiomyocytes , 2003 .

[5]  W. Allan,et al.  Long QT Syndrome , 1998, Pediatrics.

[6]  Michael Christiansen,et al.  The genetic basis of long QT and short QT syndromes: A mutation update , 2009, Human mutation.

[7]  D. Roden.  Long QT syndrome: reduced repolarization reserve and the genetic link , 2006, Journal of internal medicine.

[8]  Shulan Tian,et al.  Induced Pluripotent Stem Cell Lines Derived from Human Somatic Cells , 2007, Science.

[9]  Wojciech Zareba,et al.  Baseline Values and Sotalol‐Induced Changes of Ventricular Repolarization Duration, Heterogeneity, and Instability in Patients With a History of Drug‐Induced Torsades de Pointes , 2009, Journal of clinical pharmacology.

[10]  L. Toivonen,et al.  Further evidence of inherited long QT syndrome gene mutations in antiarrhythmic drug-associated torsades de pointes. , 2007, Heart rhythm.

[11]  Lior Gepstein,et al.  In vitro electrophysiological drug testing using human embryonic stem cell derived cardiomyocytes. , 2009, Stem cells and development.

[12]  Peter J. Schaap,et al.  Molecular characterization of the , 1997 .

[13]  J. Valentin,et al.  Strategies to reduce the risk of drug‐induced QT interval prolongation: a pharmaceutical company perspective , 2008, British journal of pharmacology.

[14]  T. Ichisaka,et al.  Induction of Pluripotent Stem Cells from Adult Human Fibroblasts by Defined Factors , 2007, Cell.

[15]  A. Camm,et al.  Relationships between preclinical cardiac electrophysiology, clinical QT interval prolongation and torsade de pointes for a broad range of drugs: evidence for a provisional safety margin in drug development. , 2003, Cardiovascular research.

[16]  M. Viitasalo,et al.  Four potassium channel mutations account for 73% of the genetic spectrum underlying long‐QT syndrome (LQTS) and provide evidence for a strong founder effect in Finland , 2004, Annals of medicine.

[17]  G. Breithardt,et al.  Life-threatening Arrhythmias Genotype-phenotype Correlation in the Long-qt Syndrome : Gene-specific Triggers for Genotype-phenotype Correlation in the Long-qt Syndrome Gene-specific Triggers for Life-threatening Arrhythmias , 2022 .

[18]  L. Peltonen,et al.  High prevalence of four long QT syndrome founder mutations in the Finnish population , 2009, Annals of medicine.

[19]  S. Yamanaka,et al.  The effects of cardioactive drugs on cardiomyocytes derived from human induced pluripotent stem cells. , 2009, Biochemical and biophysical research communications.

[20]  Divya Rajamohan,et al.  Drug evaluation in cardiomyocytes derived from human induced pluripotent stem cells carrying a long QT syndrome type 2 mutation , 2011, European heart journal.

[21]  Lior Gepstein,et al.  Cardiomyocyte Differentiation of Human Induced Pluripotent Stem Cells , 2009, Circulation.

[22]  Lei Yang,et al.  Patient-specific induced pluripotent stem cell derived models of LEOPARD syndrome , 2010, Nature.

[23]  E. Green,et al.  A molecular basis for cardiac arrhythmia: HERG mutations cause long QT syndrome , 1995, Cell.

[24]  S. Priori,et al.  Low penetrance in the long-QT syndrome: clinical impact. , 1999, Circulation.

[25]  Michael J Ackerman,et al.  Ethnic differences in cardiac potassium channel variants: implications for genetic susceptibility to sudden cardiac death and genetic testing for congenital long QT syndrome. , 2003, Mayo Clinic proceedings.

[26]  M. Viitasalo,et al.  Sinus node function and ventricular repolarization during exercise stress test in long QT syndrome patients with KvLQT1 and HERG potassium channel defects. , 1999, Journal of the American College of Cardiology.

[27]  Post‐Mortem Review and Genetic Analysis of Sudden Unexpected Death in Epilepsy (SUDEP) Cases , 2011, Brain pathology.

[28]  Shetuan Zhang.  Isolation and characterization of I(Kr) in cardiac myocytes by Cs+ permeation. , 2006, American journal of physiology. Heart and circulatory physiology.

[29]  Michael J Ackerman,et al.  Postmortem long QT syndrome genetic testing for sudden unexplained death in the young. , 2007, Journal of the American College of Cardiology.

[30]  Giuseppe Curigliano,et al.  Drug-induced prolongation of the QT interval. , 2004, The New England journal of medicine.

[31]  M. Pekkanen-Mattila,et al.  A Defined and Xeno-Free Culture Method Enabling the Establishment of Clinical-Grade Human Embryonic, Induced Pluripotent and Adipose Stem Cells , 2010, PloS one.

[32]  L. Fink,et al.  Generation and characterization of functional cardiomyocytes using induced pluripotent stem cells derived from human fibroblasts , 2009, Cell biology international.

[33]  D. Roden,et al.  Genetic susceptibility to acquired long QT syndrome: pharmacologic challenge in first-degree relatives. , 2005, Heart rhythm.

[34]  L. Studer,et al.  Induced pluripotent stem cell technology for the study of human disease , 2009, Nature Methods.

[35]  Jonathan A. Bernstein,et al.  Using iPS cells to investigate cardiac phenotypes in patients with Timothy Syndrome , 2011, Nature.

[36]  Karl-Ludwig Laugwitz,et al.  Patient-specific induced pluripotent stem-cell models for long-QT syndrome. , 2010, New England Journal of Medicine.

[37]  Rene Spijker,et al.  Differentiation of Human Embryonic Stem Cells to Cardiomyocytes: Role of Coculture With Visceral Endoderm-Like Cells , 2003, Circulation.

[38]  Tan Min Pau,et al.  Genetic structure of the snakehead murrel, Channa striata (channidae) based on the cytochrome c oxidase subunit I gene: Influence of historical and geomorphological factors , 2011, Genetics and molecular biology.

[39]  D M Roden,et al.  The long QT syndromes: genetic basis and clinical implications. , 2000, Journal of the American College of Cardiology.

[40]  R. Nagai,et al.  Novel mechanism of HERG current suppression in LQT2: shift in voltage dependence of HERG inactivation. , 1998, Circulation research.

[41]  J. Valentin,et al.  Pharmacological and electrophysiological characterization of nine, single nucleotide polymorphisms of the hERG‐encoded potassium channel , 2010, British journal of pharmacology.