axoCells™ human iPSC-derived ventricular cardiomyocytes, media, supplement and coating kit, female donor (ax5808), ≥1 million cells

Robust data validation is essential for ensuring physiological accuracy and reproducibility in cardiac research. Our ventricular cardiomyocytes are thoroughly characterized using immunocytochemistry (ICC) to confirm identity and purity, and spontaneous beating is observed within days post-thaw, demonstrating functional viability. RNA sequencing provides deep transcriptomic insights, while patch-clamp electrophysiology confirms ion channel integrity and safety pharmacology relevance. Multi-electrode array (MEA) recordings deliver precise electrical activity profiles, and functional validation in a chronic cardiotoxicity model ensures predictive performance for long-term drug safety studies. This comprehensive dataset empowers researchers to trust the fidelity of our cells for disease modeling, drug screening, and cardiac safety testing.

Phenotypic characterization: beating

Here you can see axoCells™ human iPSC-derived ventricular cardiomyocytes beating spontaneously in a smooth, synchronous monolayer. This demonstrates the high purity of the cell culture. This also demonstrates their optimization for electrophysiology assays, as you can perform spontaneous readings without the need for pacing.

axoCells™ human iPSC-derived ventricular cardiomyocytes beating spontaneously at 0.8Hz prior to cryopreservation. Video obtained using 10x magnification, 90fps.

Phenotypic characterization: ICC

Here you can see axoCells^TM ventricular cardiomyocytes expressing key markers of maturity and chamber-specificity. Expression of chamber-specific markers forms part of our QC for these cells. You can also appreciate the expected morphology with clear banding patterns.

1. Immunocytochemistry of axoCellsTM ventricular cardiomyocytes stained for myomesin (green) and actin (red). This image illustrates the presence of the M-line within the sarcomere, the contractile unit of cardiomyocytes. Magnification 63x oil objective. Scale bar = 20 µm
2. Immunocytochemistry of axoCellsTM cardiomyocytes stained for MLC2V (red) and MLC2A (green). Demonstrated is the mixture of ventricular (MLC2V) and atrial (MLC2A) Cardiomyocytes within the culture. Magnification 63x oil objective. Scale bar = 20 µm
3. Immunocytochemistry of axoCellsTM ventricular cardiomyocytes stained for cardiac alpha-actinin (green) and cardiac troponin T (red). This image illustrates the presence of the sarcomere, the contractile unit of cardiomyocytes. Magnification 40x
4. Immunocytochemistry of axoCellsTM ventricular cardiomyocytes stained for vimentin (red) and cardiac troponin T (green). Vimentin is a major filament protein in non-muscle cells whilst cardiac troponin T is a sarcomeric protein found in cardiomyocytes.

Phenotypic characterization: RNA sequencing

Here you can see distinct expression patterns between our standard cardiac maintenance media and MyoMax, demonstrating their functional maturity. The utility of iPSC-derived cells over traditional hERG overexpression models can be further appreciated by the expression of multiple ion channels (allowing more physiologically-relevant models) and specific calcium handling machinery, which traditional models often lack.

Overall, this demonstrates the value of axoCells cardiomyocytes in chamber-specific, physiologically-relevant cardiac models.

TempO-Seq transcriptomic analysis shows upregulated sarcomeric genes (e.g. TNNI3, TNNT2), downregulated atrial genes (e.g. NPPA, TBX5) and upregulated fatty acid metabolism genes (e.g. MDH1, FABP3).

Functional relevance: patch clamp

Here we show an example of functional validation of our axoCells ventricular cardiomyocytes against 3 major drug classes: Lidocaine (an Na+ channel blocker), Nifedipine (a Ca2+ channel blocker) and Dofetilide (a hERG channel blocker), measured by patch clamp, which is the “gold standard” electrophysiology method. There is expected response to the major drug classes, validating these cells for use in in vitro cardiac models.

axoCells human iPSC-derived ventricular cardiomyocytes express the core cardiac ion channels INa, ICa,L and IKr. (A) Representative traces of evoked action potentials recorded under control conditions (grey) and in the presence of 100 μM Lidocaine (green), 100 nM Nifedipine (blue) or 50 nM Dofetilide (red), which show expected effects on action potential amplitude and duration. B) Average effect of each compound on spontaneous action potential parameters, presented as percent of control ± SEM, N ≥ 4. Statistical significance calculated by a paired two-tailed Student’s t-test (* p<0.05, ** p<0.01, *** p<0.001).

Functional characterization: MEA

We’ve extensively characterized our axoCells ventricular cardiomyocytes using our industry-leading Axion Maestro Pro MEA system, which we also use for our axoServices electrophysiology assays.

Here you can see a physiological waveform at base, and then the expected electrophysiological response to Dofetilide (a commercially available hERG blocker), demonstrating the functional relevance of our axoCells ventricular cardiomyocytes.

Improved electrophysiological parameters of day 14 axoCells ventricular cardiomyocytes measured using the Axion Maestro Pro MEA system. MyoMax treated cells exhibit shorter FPD, faster conduction velocity and lower beat rate.