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Induced pluripotent stem cell derived cardiomyocytes and multivariate analysis for detection of potential QT perturbation
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Abstracts
Poster Number: 21 Board Number: 21 In vitro rat hippocampal slice model for pro-convulsion liability assessment Xian Chena, Sunny Z. Suna, Richard Newmanb, Karen Tseb, Gareth Waldronb, Bernard Ferminia, Jill Steidl-Nicholsa a
Global Safety Pharmacology, Pfizer Global R&D, Groton, CT, United States Global Safety Pharmacology, Pfizer Global R&D, Sandwich, Kent, United Kingdom
b
Drug-induced convulsion is a major adverse effect that hinders drug development. The aim of this study was to define and validate appropriate end points using a rat hippocampal slice model for proconvulsion liability assessment, and correlate the in vitro data with corresponding in vivo data. Evoked population spikes (PS) were recorded using the MED64 multi-electrode array system from the CA1 cell body layer in 4 coronal slices simultaneously at 21 °C, with stimulations every 30 s at the Schaffer collateral pathway. Eight end points, including area with respect to 0 mV, PS area, PS number, peak amplitude and conduction time were obtained for ten compounds. 4-AP, PTZ, caffeine, and theophylline increased PS number with the onset of multiple population spikes of a similar pattern. 4-AP, pilocarpine, bupropion and two project compounds which produced convulsions in vivo, A and B, prolonged the conduction time measured from the stimulation to the first PS peak. No changes in these two parameters were observed for negative controls diazepam or C, which is similar to A and B but does not cause seizures in vivo. In vitro concentrations were compared to in vivo plasma and CSF exposures that produced full convulsion or pre-convulsive symptoms as measured by a modified Racine scale. These data establish that a combination of PS properties and conduction time is a better quantitative predictor of in vivo convulsion than PS properties alone, and demonstrate that rat hippocampal slice can be a useful model for pro-convulsion liability assessment during drug development. doi:10.1016/j.vascn.2010.11.025
Poster Number: 22 Board Number: 22 Induced pluripotent stem cell derived cardiomyocytes and multivariate analysis for detection of potential QT perturbation Blake D. Ansona, Junyi Maa, Steven Fienea, Simon Bryantb, Richard Healb, Scott Nicollb a
Cellular Dynamics International, Inc., Madison, WI, United States VivoMedica Ltd., Sittingbourne, United Kingdom
distinct classes of compounds. Isoprenaline increased beat rate and reduced sfAP duration, E4031 prolonged while nifedipine shortened sfAP durations, respectively, and TTX produced interspike interval variability with quiescent episodes. Conclusion: iPS-cardiomyocyte sfAP waveform modulation by pharmacological agents was in agreement with their well characterized cardiac effects. The ability to quantify these changes in a human-based model system, to discriminate between different modes of drug action using DrugPrint® analysis software, and the overall ease of use provides an excellent in vitro system for detecting drug-induced changes in cardiac electrophysiology. doi:10.1016/j.vascn.2010.11.026
Poster Number: 23 Board Number: 23 Stem cell-derived human cardiomyocyte action potential assay for cardiac risk evaluation Andrew Bruening-Wright, Shengde Peng, Glenn E. Kirsch, Arthur M. Brown ChanTest Corporation, Cleveland, OH, United States Non-human Purkinje fiber (PF) action potential (AP) assays are commonly used to assess cardiac risk of pharmaceuticals in preclinical development, but the recent availability of human embryonic stem cellderived cardiomyocytes (hESC-CMs) offers potential advantages. The electrophysiological and pharmacological profiles of hESC-CMs were compared to rabbit and canine PFs. The effects of reference compounds were measured in ventricular-type hESC-CMs by perforated-patch, current clamp recording and compared with results obtained in PF AP assays. AP prolongation in hESC-CMs was observed upon exposure to hERG channel blockers (terfenadine, quinidine, cisapride, sotalol, E-4031 and verapamil), with shorter latencies than in PF assays. For torsadogenic compounds terfenadine and quinidine, hESC-CM sensitivity to AP prolongation was greater than that observed in either the canine or rabbit PF assays. Moreover, the IKs blocker chromanol 293B prolonged APs from hESC-CMs, whereas both rabbit and canine PF assays are known to be insensitive to IKs blockers in the absence of adrenergic preconditioning. In conclusion, hESC-CMs provide an attractive alternative to PF AP assays; the hESC-CM assay is conducted in human myocytes, removes diffusion delays with consequent reduced test compound consumption, and demonstrates an overall pharmacological sensitivity that is superior to conventional rabbit or canine PF assays.
doi:10.1016/j.vascn.2010.11.027
b
Accurate assessment of potential QT perturbation with single ion channel test systems requires multiple assays per drug. Induced pluripotent stem cell derived cardiomyocytes (iPS-cardiomyocytes) and multivariate analysis provide an integrated, single pass approach for detecting drug-induced changes in cardiac electrophysiology of early stage lead compounds. Aims: (1) quantify drug-induced changes in spontaneous field potentials (sfAP) recorded from human iPS-cardiomyocytes; and (2) assess the suitability of this combined bioassay/analytical system for profiling NCEs. Methods: Syncytial monolayers of iPS-cardiomyocytes were cultured onto multi-electrode arrays (MEAs; MCS, Germany). Waveforms were recorded with a 60channel amplifier at 37 °C, digitized at a rate of 10 kHz, and processed offline with DrugPrint® analysis software. Results: The sfAP waveform profile was modified differently by submaximal applications of
Poster Number: 24 Board Number: 24 Plug and play for the patch clamp technology: Frozen instant cells in direct comparison to permanently cultured cells Gesa Rascher-Eggstein, Olaf Scheel, Thomas Knott Cytocentrics AG, Rostock, Meck-Vorp, Germany Manual and automated patch clamp is established for several years in the ion channel drug discovery and safety pharmacology. However, the technique is very complex and difficult to standardize. In particular the cell quality is crucial for reliable data and adequate success rates. Exclusive for patch clamp applications we have
Abstracts
Poster Number: 21 Board Number: 21 In vitro rat hippocampal slice model for pro-convulsion liability assessment Xian Chena, Sunny Z. Suna, Richard Newmanb, Karen Tseb, Gareth Waldronb, Bernard Ferminia, Jill Steidl-Nicholsa a
Global Safety Pharmacology, Pfizer Global R&D, Groton, CT, United States Global Safety Pharmacology, Pfizer Global R&D, Sandwich, Kent, United Kingdom
b
Drug-induced convulsion is a major adverse effect that hinders drug development. The aim of this study was to define and validate appropriate end points using a rat hippocampal slice model for proconvulsion liability assessment, and correlate the in vitro data with corresponding in vivo data. Evoked population spikes (PS) were recorded using the MED64 multi-electrode array system from the CA1 cell body layer in 4 coronal slices simultaneously at 21 °C, with stimulations every 30 s at the Schaffer collateral pathway. Eight end points, including area with respect to 0 mV, PS area, PS number, peak amplitude and conduction time were obtained for ten compounds. 4-AP, PTZ, caffeine, and theophylline increased PS number with the onset of multiple population spikes of a similar pattern. 4-AP, pilocarpine, bupropion and two project compounds which produced convulsions in vivo, A and B, prolonged the conduction time measured from the stimulation to the first PS peak. No changes in these two parameters were observed for negative controls diazepam or C, which is similar to A and B but does not cause seizures in vivo. In vitro concentrations were compared to in vivo plasma and CSF exposures that produced full convulsion or pre-convulsive symptoms as measured by a modified Racine scale. These data establish that a combination of PS properties and conduction time is a better quantitative predictor of in vivo convulsion than PS properties alone, and demonstrate that rat hippocampal slice can be a useful model for pro-convulsion liability assessment during drug development. doi:10.1016/j.vascn.2010.11.025
Poster Number: 22 Board Number: 22 Induced pluripotent stem cell derived cardiomyocytes and multivariate analysis for detection of potential QT perturbation Blake D. Ansona, Junyi Maa, Steven Fienea, Simon Bryantb, Richard Healb, Scott Nicollb a
Cellular Dynamics International, Inc., Madison, WI, United States VivoMedica Ltd., Sittingbourne, United Kingdom
distinct classes of compounds. Isoprenaline increased beat rate and reduced sfAP duration, E4031 prolonged while nifedipine shortened sfAP durations, respectively, and TTX produced interspike interval variability with quiescent episodes. Conclusion: iPS-cardiomyocyte sfAP waveform modulation by pharmacological agents was in agreement with their well characterized cardiac effects. The ability to quantify these changes in a human-based model system, to discriminate between different modes of drug action using DrugPrint® analysis software, and the overall ease of use provides an excellent in vitro system for detecting drug-induced changes in cardiac electrophysiology. doi:10.1016/j.vascn.2010.11.026
Poster Number: 23 Board Number: 23 Stem cell-derived human cardiomyocyte action potential assay for cardiac risk evaluation Andrew Bruening-Wright, Shengde Peng, Glenn E. Kirsch, Arthur M. Brown ChanTest Corporation, Cleveland, OH, United States Non-human Purkinje fiber (PF) action potential (AP) assays are commonly used to assess cardiac risk of pharmaceuticals in preclinical development, but the recent availability of human embryonic stem cellderived cardiomyocytes (hESC-CMs) offers potential advantages. The electrophysiological and pharmacological profiles of hESC-CMs were compared to rabbit and canine PFs. The effects of reference compounds were measured in ventricular-type hESC-CMs by perforated-patch, current clamp recording and compared with results obtained in PF AP assays. AP prolongation in hESC-CMs was observed upon exposure to hERG channel blockers (terfenadine, quinidine, cisapride, sotalol, E-4031 and verapamil), with shorter latencies than in PF assays. For torsadogenic compounds terfenadine and quinidine, hESC-CM sensitivity to AP prolongation was greater than that observed in either the canine or rabbit PF assays. Moreover, the IKs blocker chromanol 293B prolonged APs from hESC-CMs, whereas both rabbit and canine PF assays are known to be insensitive to IKs blockers in the absence of adrenergic preconditioning. In conclusion, hESC-CMs provide an attractive alternative to PF AP assays; the hESC-CM assay is conducted in human myocytes, removes diffusion delays with consequent reduced test compound consumption, and demonstrates an overall pharmacological sensitivity that is superior to conventional rabbit or canine PF assays.
doi:10.1016/j.vascn.2010.11.027
b
Accurate assessment of potential QT perturbation with single ion channel test systems requires multiple assays per drug. Induced pluripotent stem cell derived cardiomyocytes (iPS-cardiomyocytes) and multivariate analysis provide an integrated, single pass approach for detecting drug-induced changes in cardiac electrophysiology of early stage lead compounds. Aims: (1) quantify drug-induced changes in spontaneous field potentials (sfAP) recorded from human iPS-cardiomyocytes; and (2) assess the suitability of this combined bioassay/analytical system for profiling NCEs. Methods: Syncytial monolayers of iPS-cardiomyocytes were cultured onto multi-electrode arrays (MEAs; MCS, Germany). Waveforms were recorded with a 60channel amplifier at 37 °C, digitized at a rate of 10 kHz, and processed offline with DrugPrint® analysis software. Results: The sfAP waveform profile was modified differently by submaximal applications of
Poster Number: 24 Board Number: 24 Plug and play for the patch clamp technology: Frozen instant cells in direct comparison to permanently cultured cells Gesa Rascher-Eggstein, Olaf Scheel, Thomas Knott Cytocentrics AG, Rostock, Meck-Vorp, Germany Manual and automated patch clamp is established for several years in the ion channel drug discovery and safety pharmacology. However, the technique is very complex and difficult to standardize. In particular the cell quality is crucial for reliable data and adequate success rates. Exclusive for patch clamp applications we have