Introduction
- A highly purified population of cardiomyocytes, differentiated from human induced pluripotent stem (iPS) cells (Cellular Dynamics iCell® Cardiomyocytes), are used.
- The cells are a mixture of spontaneously electrically-active atrial, nodal, and ventricular-like myocytes. They possess typical human heart cell characteristics forming electrically connected syncytial layers that beat in synchrony, and exhibit expected electrophysiological and biochemical responses upon reference drug exposure.
- Viability is maintained for an extended culture periods (up to 2 weeks) allowing for acute and chronic studies.
- Microelectrode array (MEA) is one of the most sophisticated and efficacious technologies for measuring changes in spontaneously-active cells, such as cardiomyocytes and neurons.
- Cyprotex’s eCiphr®Cardio is a cell-based assay which uses MEA recording to monitor electrophysiological activity by measuring beat rate, field potential duration, amplitude and conduction velocity.
- Unlike the patch-clamp hERG assay, eCiphr®Cardio assesses changes in all major ion channels implicated in an action potential.
- This cardiac assay provides a unique in vitro system for preclinical drug discovery, cardiotoxicity assessment, disease modelling and high throughput phenotypic screening of drug candidates.
Protocol
eCiphr®Cardio Cell Based Assay Protocol
Data
Data from Cyprotex's eCiphr®Cardio Assay
Figure 1
Raw traces for vehicle control (0.1% DMSO) and test compound (verapamil).
Red arrows point to the field potential duration (FPD, indicative of the QT interval duration). Verapamil clearly shortens FPD as compared to 0.1% DMSO (vehicle control). Note: In order to distinguish between the two traces, the voltage for verapamil is purposely shifted upward.
References
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