title: Action potential characterization of human induced pluripotent stem cell-derived cardiomyocytes using automated patch-clamp technology.
abstract: Recent progress in embryonic stem cell (ESC) and induced pluripotent stem cell (iPSC) research led to high-purity preparations of human cardiomyocytes (CMs) differentiated from these two sources-suitable for tissue regeneration, in vitro models of disease, and cardiac safety pharmacology screening. We performed a detailed characterization of the effects of nifedipine, cisapride, and tetrodotoxin (TTX) on Cor.4U(®) human iPSC-CM, using automated whole-cell patch-clamp recordings with the CytoPatch™ 2 equipment, within a complex assay combining multiple voltage-clamp and current-clamp protocols in a well-defined sequence, and quantitative analysis of several action potential (AP) parameters. We retrieved three electrical phenotypes based on AP shape: ventricular, atrial/nodal, and S-type (with ventricular-like depolarization and lack of plateau). To suppress spontaneous firing, present in many cells, we injected continuously faint hyperpolarizing currents of -10 or -20 pA. We defined quality criteria (both seal and membrane resistance over 1 GΩ), and focused our study on cells with ventricular-like AP. Nifedipine induced marked decreases in AP duration (APD): APD90 (49.8% and 40.8% of control values at 1 and 10 μM, respectively), APD50 (16.1% and 12%); cisapride 0.1 μM increased APD90 to 176.2%; and tetrodotoxin 10 μM decreased maximum slope of phase to 33.3% of control, peak depolarization potential to 76.3% of control, and shortened APD90 on average to 80.4%. These results prove feasibility of automated voltage- and current-clamp recordings on human iPSC-CM and their potential use for in-depth drug evaluation and proarrhythmic liability assessment, as well as for diagnosis and pharmacology tests for cardiac channelopathy patients.
authors.affiliation: 1 Cytocentrics Bioscience GmbH , Rostock, Germany .
authors.forename: Olaf
authors.initials: O
authors.lastname: Scheel
authors.forename: Stefanie
authors.initials: S
authors.lastname: Frech
authors.forename: Bogdan
authors.initials: B
authors.lastname: Amuzescu
authors.forename: Jörg
authors.initials: J
authors.lastname: Eisfeld
authors.forename: Kun-Han
authors.initials: KH
authors.lastname: Lin
authors.forename: Thomas
authors.initials: T
authors.lastname: Knott
mesh_terms: D000200:Action Potentials / Q000187:drug effects*; D000779:Anesthetics, Local / Q000494:pharmacology; D001331:Automation; D002121:Calcium Channel Blockers / Q000494:pharmacology; D002478:Cells, Cultured; D020117:Cisapride / Q000494:pharmacology; D006801:Humans; D057026:Induced Pluripotent Stem Cells / Q000187:drug effects*; D032383:Myocytes, Cardiac / Q000187:drug effects*; D009543:Nifedipine / Q000494:pharmacology; D018408:Patch-Clamp Techniques / Q000379:methods*; D015203:Reproducibility of Results; D017366:Serotonin Receptor Agonists / Q000494:pharmacology; D013779:Tetrodotoxin / Q000494:pharmacology
chemical_list: D000779:Anesthetics, Local; D002121:Calcium Channel Blockers; D017366:Serotonin Receptor Agonists; D013779:Tetrodotoxin; D009543:Nifedipine; D020117:Cisapride