Alterations in Human Induced Pluripotent Stem Cell Derived Cardiomyocyte Electrophysiology: The Impact of Temporal Changes and Study Parameters on Experimental Reproducibility

Background: Human induced pluripotent stem cell derived cardiomyocytes (hiPSC-CM) have been used as an experimental model to investigate cardiac physiology, electrophysiology (EP), and drug toxicity. Despite the broad use of hiPSC-CM in biomedical research, the experimental technical approaches used to maintain hiPSC-CM and conduct electrophysiology studies can vary between laboratories, which can impact the resultant data. Objective: To quantify daily developmental changes in hiPSC-CM physiology over a two-week period, and optimize EP recording techniques to improve reproducibility across hiPSC-CM studies. Methods: hiPSC-CM were plated on 24-well microelectrode (MEA) plates and EP measurements were recorded daily for two weeks. RNA was isolated from hiPSC-CM on post-defrost day 4, 7, and 10 to monitor cell maturation. hiPSC-CM EP parameters were measured at baseline and after exposure to the drugs E-4031, nifedipine, and isoproterenol on post-defrost day 4, 7, and 10. Results: Across the two-week timeframe, hiPSC-CM spontaneous beating rate slowed daily until reaching a plateau around post-defrost day 10 (-27%; day 2: 53.8 ± 5.1 BPM to day 10: 39.4 ± 6.8 BPM), which effected other rate-dependent measurements including the field potential duration (FPD) (day 2: 288.9 ± 14 ms to day 10: 505.9 ± 59 ms). Spike amplitude also increased over two-weeks, with most significant changes occurring with the first week (+717% from baseline day 2: 0.30 ± 0.03 mV to day 7: 2.45 ± 0.8 mV). Action potential duration at 90% repolarization also lengthened from 0.319 ± 0.02s on day 4 to 0.402 ± 0.02s on day 10. Gene expression studies suggest that hiPSC-CM continue to mature during two-weeks of cell culture, and these daily differences impacted cellular responses to various drug treatments (E4031, nifedipine, isoproterenol). Conclusion: Length of cell culture and variations in other technical recording parameters can alter hiPSC-CM basal physiology and responses to various drug treatments. To increase rigor and improve experimental reproducibility, care should be taken to utilize hiPSC-CM within a short timeframe (e.g., 6-8 days post-culture) and experimental techniques should be thoroughly reported.

Author

• Pressman, Jenna

Language

• en

Date created

• 2023

Type of Work

• Master's Thesis

License

• All rights reserved

Rights statement

• In Copyright

GW Unit

• Biomedical Engineering

Degree

• M.S.

Advisor

• Kay, Matthew
• Posnack, Nikki

Committee Member(s)

• Zderic, Vesna

Persistent URL

•  https://scholarspace.library.gwu.edu/etd/6h440t33q