Single-Cell Mechanical Analysis of Human Pluripotent Stem Cell-Derived Cardiomyocytes for Drug Testing and Pathophysiological Studies

Abstract

Summary Current platforms for studying the mechanical properties of human pluripotent stem cell-derived cardiomyocytes (hPSC-CMs) as single cells do not measure forces directly, require numerous assumptions, and cannot study cell mechanics at different loading conditions. We present a method for directly measuring the active and passive forces generated by single-cell hPSC-CMs at different stretch levels. Utilizing this technique, single hPSC-CMs exhibited positive length-tension relationship and appropriate inotropic, klinotropic, and lusitropic changes in response to pharmacological treatments (isoproterenol and verapamil). The unique potential of the approach for drug testing and disease modeling was exemplified by doxorubicin and omecamtiv mecarbil drug studies revealing their known actions to suppress (doxorubicin) or augment (omecamtiv mecarbil at low dose) cardiomyocyte contractility, respectively. Finally, mechanistic insights were gained regarding the cellular effects of these drugs as doxorubicin treatment led to cellular mechanical alternans and high doses of omecamtiv mecarbil suppressed contractility and worsened the cellular diastolic properties.

Dense optical flow software to quantify cellular contractility

“…Measurements of contractility have been widely used for research on both adult and neonatal myocytes ( Belostotskaya and Golovanova, 2014 ; Berger et al., 1994 ; Boudreau-Béland et al., 2015 ; Harary and Farley, 1960 ; Haworth et al., 1987 ; Hissa et al., 2017 ; Jesus et al., 2020 ; Penitente et al., 2014 ; Ramadan et al., 2018 ). More recently, human induced pluripotent stem cell-derived CMs (hiPSC-CMs) have been employed as a model for human cardiac disease and drug screening ( Ballan et al., 2020 ; Birket et al., 2015 ; Gong and Sobie, 2018 ; Lahti et al., 2012 ; Lan et al., 2013 ; Ribeiro et al., 2015 ; Wang et al., 2014 , 2019 ). The development of this new experimental model, although showing great promise, also brings some challenges to efficiently detect CM contraction dynamics.…”

Direct Contraction Force Measurements of Engineered Cardiac Tissue Constructs With Inotropic Drug Exposure

“…However, varying inotropic effects have also been reported. Measuring from single-cell hiPSC-CMs, Ballan et al (2020) reported 11% increase in force at 100 nM but higher doses, 1 and 10 µM, suppressed contractility. Ribeiro et al (2017) , also measuring single-cell hiPSC-CMs, reported positive inotropy immediately after administration of 100 nM omecamtiv mecarbil.…”

Targeted therapies in genetic dilated and hypertrophic cardiomyopathies: from molecular mechanisms to therapeutic targets. A position paper from the Heart Failure Association (HFA) and the Working Group on Myocardial Function of the European Society of Cardiology (ESC)

“… 110 Moreover, relevant non‐myocyte cardiac cells such as vascular, cardiac fibroblasts, epicardial and endocardial precursor cells could also be generated, allowing to construct more clinically relevant cardiac‐like structures and asses the role of non‐myocyte/cardiomyocyte crosstalk in cardiac pathologies. Similarly, ongoing efforts are focused on enhancing hiPSC‐CM maturation through the use of thyroid and glucocorticoid hormones, 111 the effects of extracellular‐matrix and tissue‐engineering strategies, mechanical and electrical training, changes in the metabolic fuel to free fatty acids, and other interventions.…”