Isogenic human pluripotent stem cell pairs reveal the role of a KCNH2 mutation in long-QT syndrome

Abstract

Patient-specific induced pluripotent stem cells (iPSCs) will assist research on genetic cardiac maladies if the disease phenotype is recapitulated in vitro. However, genetic background variations may confound disease traits, especially for disorders with incomplete penetrance, such as long-QT syndromes (LQTS). To study the LQT2-associated c.A2987T (N996I) KCNH2 mutation under genetically defined conditions, we derived iPSCs from a patient carrying this mutation and corrected it. Furthermore, we introduced the same point mutation in human embryonic stem cells (hESCs), generating two genetically distinct isogenic pairs of LQTS and control lines. Correction of the mutation normalized the current (IKr) conducted by the HERG channel and the action potential (AP) duration in iPSC-derived cardiomyocytes (CMs). Introduction of the same mutation reduced IKr and prolonged the AP duration in hESC-derived CMs. Further characterization of N996I-HERG pathogenesis revealed a trafficking defect. Our results demonstrated that the c.A2987T KCNH2 mutation is the primary cause of the LQTS phenotype. Precise genetic modification of pluripotent stem cells provided a physiologically and functionally relevant human cellular context to reveal the pathogenic mechanism underlying this specific disease phenotype.

Integrating cardiomyocytes from human pluripotent stem cells in safety pharmacology: has the time come?

“…In addition, hiPSC‐CMs are also being used as model systems to test the effect of both known and novel drugs on cardiac channelopathies (Matsa et al , 2011; Zhang et al , 2012; Bellin et al , 2013; Di Pasquale et al , 2013; Zhang et al , 2014), with suppression of pathological pro‐arrhythmic potential and restoration of altered AP duration (APD) being two main endpoints. Clinical evidence has shown that pharmacological treatments can be of more benefit when properly calibrated in a disease‐specific or even mutation‐specific manner (Nebert and Vesell, 2006; Cavallari, 2012; Amin and Wilde, 2016; Itoh et al , 2016; Martiniano et al , 2016).…”

“…The green area defines the normal QT interval range for humans. Data are shown as mean ± SD: 1, (Malan et al , 2016); 2, (Rocchetti/Sala et al , unpublished); 3, (Zhang et al , 2014); 4, (Zhang et al , 2014); 5, (Davis et al , 2012); 6, (Rocchetti/Sala et al , unpublished); 7, (Bellin et al , 2013); 8, (Sala et al , 2016); 9, (Bizy et al , 2013); 10, (Ma et al , 2013); 11, (Ma et al , 2015); 12, (Ma et al , 2015); 13, (Gibson et al , 2014a); 14, (Itzhaki et al , 2011); 15, (Gibson et al , 2014c); 16, (Lu et al , 2014); 17, (Gibson et al , 2014b); 18, (Mehta et al , 2014). (B) and (C) Composition of extracellular buffers (B) and pipette solutions (C) for current clamp experiments.…”

Transcriptome of human foetal heart compared with cardiomyocytes from pluripotent stem cells

“…The dendrograms illustrate clustering of the hPSC-CMs with the first and second trimester foetal heart samples. potentials in patch clamp electrophysiology (Davis et al, 2012;Bellin et al, 2013) and by excluding the NKX2.5-GFP − cardiomyocytes, we also excluded pacemaker-like cells (Birket et al 2015). Furthermore, we also examined hESC-derived CMs that were cultured in commercially available maturation medium (MM) containing T3 hormone as a principal component .…”

Myocardial Reprogramming Medicine: The Development, Application, and Challenge of Induced Pluripotent Stem Cells

“…Finally, iPSCderived myocardium can be used to reproduce the in vitro characteristics of familial hypertrophic cardiomyopathy [230,231], right ventricular cardiomyopathy [232], and cardiac Na + channel disease [233,234]. These iPSC-derived cell models can provide a physiologically and functionally relevant human cellular context in vitro to reveal the pathogenic mechanism underlying the specific disease phenotype [235].…”