Contents lists available at ScienceDirect Biosensors and Bioelectronics journal homepage: www.elsevier.com/locate/bios Non-invasive electromechanical cell-based biosensors for improved investigation of 3D cardiac models Guido Caluori a,b,c , Jan Pribyl a , Martin Pesl b,d,e , Sarka Jelinkova d , Vladimir Rotrekl d , Petr Skladal a, ⁎ , Roberto Raiteri c, ⁎ a Central European Institute of Technology, Masaryk University, Kamenice 5, 62500 Brno, Czech Republic b International Clinical Research Centre of Saint Anne Hospital Brno, Pekarska 53, 60200 Brno, Czech Republic c Department of Informatics, Bioengineering Robotics and Systems Engineering, University of Genova, Via All'Opera Pia, 13, 16145 Genova, Italy d Department of Biology, Faculty of Medicine, Masaryk University, Kamenice 5, 62500 Brno, Czech Republic e 1st Department of Cardiovascular Diseases, St. Anne's University Hospital and Masaryk University, Pekarska 53, Brno, Czech Republic ARTICLE INFO Keywords: Excitation-contraction coupling Human pluripotent stem cells Cardiomyocytes Atomic force microscopy Microelectrode array Drug testing ABSTRACT Cardiomyocytes (CM) placed on microelectrode array (MEA) were simultaneously probed with cantilever from atomic force microscope (AFM) system. This electric / nanomechanical combination in real time recorded beating force of the CMs cluster and the triggering electric events. Such "organ-on-a-chip" represents a tool for drug development and disease modeling. The human pluripotent stem cells included the WT embryonic line CCTL14 and the induced dystrophin deficient line reprogrammed from fibroblasts of a patient affected by Duchenne Muscular Dystrophy (DMD, complete loss of dystrophin expression). Both were differentiated to CMs and employed with the AFM/MEA platform for diseased CMs’ drug response testing and DMD characterization. The dependence of cardiac parameters on extracellular Ca 2+ was studied. The differential evaluation explained the observed effects despite variability of biological samples. The β-adrenergic stimulation (isoproterenol) and antagonist trials (verapamil) addressed ionotropic and chronotropic cell line-dependent features. For the first time, a distinctive beating-force relation for DMD CMs was measured on the 3D cardiac in vitro model. 1. Introduction In the field of cell-based biosensors, cardiomyocytes (CM) are often used as models to study heart related diseases. The monitoring of electric activities of CMs is typically chosen; (multi)electrode transdu- cers seem well established and widely available as microelectrode ar- rays (MEA) (Rothermel et al., 2005). The beating of CMs can be fol- lowed relatively easily (e.g. by video microscopy, Laurila et al., 2015), though in many situations the missing information on the associated beating force is of paramount importance in heart remodeling pathol- ogies, such as dystrophinopathies and cardiomyopathies (Vatta et al., 2005). Beating force is associated with pathophysiological electro-me- chanical coupling, and its alterations result often in mechanical heart failure (Pesl et al., 2016a). Such biomechanical measurements in- vestigating the dilated cardiomyopathy were previously done on CMs using the stretcher device (Knoll et al., 2002). More detailed in- vestigations were later done using cantilevers as nanomechanical transducers and atomic force microscope (AFM) as the evaluation system in real time with individual cardiomyocyte cells (Liu et al., 2012a,2012b) or cell clusters (Pesl et al., 2016a). Thus, combination of AFM for biomechanical changes with MEA sensing electric signals de- scribed here seems naturally promising for elucidating complex events in cardiomyocytes obtained from patient derived stem cells. This ap- proach provides a robust and convenient example of the organ-on-a- chip system demonstrating its capabilities on disease related CMs. Supplementary material related to this article can be found online at doi:10.1016/j.bios.2018.10.021. The introduction of human pluripotent stem cells (hPSC, either embryonic, hESC, or induced pluripotent, hiPSC) and cardiac differ- entiation protocols allowed almost two decades of study on the cardiac organogenesis and functionality. In particular, patient-specific hiPSC representing a direct supply of healthy and mutation-carrying samples (Sinnecker et al., 2014) allow for description of the diseases progression involved in heart failure (Moretti et al., 2013). To improve the com- parison between in vitro models, CRISPR-Cas9 technology has recently gained an outstanding popularity for its efficiency and flexibility in inducing precise mutations in cell lines, providing researchers with isogenic controls (Motta et al., 2017). hPSC-derived cardiomyocytes https://doi.org/10.1016/j.bios.2018.10.021 Received 1 July 2018; Received in revised form 11 October 2018; Accepted 11 October 2018 ⁎ Corresponding authors. E-mail addresses: skladal@chemi.muni.cz (P. Skladal), roberto.raiteri@unige.it (R. Raiteri). Biosensors and Bioelectronics 124–125 (2019) 129–135 Available online 16 October 2018 0956-5663/ © 2018 Elsevier B.V. All rights reserved. T