hiPSC-derived cardiomyocytes: A robust and reproducible QPatch® II assay for Nav1.5 measurements

The Na_V1.5 channel is critical in maintaining the physiological electrical function in cardiomyocytes (CMs). Consequently, high-throughput measurements of Na_V1.5 currents (I_Na) in hiPSC-CMs are useful e.g. in the characterization of cardiac disease phenotypes and compound testing. QPatch II has been demonstrated as a capable platform for such measurements, and here, we present a high-performance Na_V1.5 assay using iCell^® Cardiomyocytes (hiPSC-CMs) from FUJIFILM Cellular Dynamics with:

• Assay success rates ~45% with more than 85% hiPSC CMs expressing I_Na with peak currents |I_Na|> 200 pA (at -30 mV)
• Biophysical characterization with activation/inactivation potentials in agreement with literature values
• Cumulative compound concentration response of the local anaesthetic agent tetracaine with IC₅₀ values in agreement
  with literature values