Automated Patch Clamp Recordings of Human Stem Cell-Derived Cardiomyocytes

Abstract

Patch clamp remains the gold standard for studying ion channel activity within cell membranes. Conventional patch clamp is notoriously low throughput and technically demanding making it an unsuitable technique for high-throughput screening (HTS). Automated patch clamp (APC) devices have done much to increase throughput and improve ease of use, particularly when using standard cell line cells such as HEK and CHO. In recent years, however, the use of human-induced pluripotent stem cells (hiPSCs) has become increasingly important, especially for safety screening in response to the Comprehensive In Vitro Proarrhythmia Assay (CiPA) initiative introduced in 2013. The goal of this initiative is to standardize assays, targets, and cell types. One part of the paradigm focuses on the use of APC and hiPSC cardiomyocytes. This chapter describes two automated patch clamp devices recording from up to 8 or 384 cells simultaneously using hiPSC cardiomyocytes. In the voltage clamp mode, voltage-gated Na+ (NaV), Ca2+ (CaV), and K+ (KV) channels could be recorded, and pharmacology using tetracaine, a NaV channel blocker, is described. Additionally, action potentials in the current clamp mode were recorded, and examples are shown including the effect of nifedipine, a CaV channel blocker. Detailed methods are provided for cell culture and harvesting of hiPSCs for use on APC devices. Protocols are also provided for voltage and current clamp recordings on the Patchliner, and voltage clamp experiments on the SyncroPatch 384PE APC instruments.