title: Cardiac Non-myocyte Cells Show Enhanced Pharmacological Function Suggestive of Contractile Maturity in Stem Cell Derived Cardiomyocyte Microtissues.
abstract: The immature phenotype of stem cell derived cardiomyocytes is a significant barrier to their use in translational medicine and pre-clinical in vitro drug toxicity and pharmacological analysis. Here we have assessed the contribution of non-myocyte cells on the contractile function of co-cultured human embryonic stem cell derived cardiomyocytes (hESC-CMs) in spheroid microtissue format. Microtissues were formed using a scaffold free 96-well cell suspension method from hESC-CM cultured alone (CM microtissues) or in combination with human primary cardiac microvascular endothelial cells and cardiac fibroblasts (CMEF microtissues). Contractility was characterized with fluorescence and video-based edge detection. CMEF microtissues displayed greater Ca(2+ )transient amplitudes, enhanced spontaneous contraction rate and remarkably enhanced contractile function in response to both positive and negative inotropic drugs, suggesting a more mature contractile phenotype than CM microtissues. In addition, for several drugs the enhanced contractile response was not apparent when endothelial cell or fibroblasts from a non-cardiac tissue were used as the ancillary cells. Further evidence of maturity for CMEF microtissues was shown with increased expression of genes that encode proteins critical in cardiac Ca(2+ )handling (S100A1), sarcomere assembly (telethonin/TCAP) and β-adrenergic receptor signalling. Our data shows that compared with single cell-type cardiomyocyte in vitro models, CMEF microtissues are superior at predicting the inotropic effects of drugs, demonstrating the critical contribution of cardiac non-myocyte cells in mediating functional cardiotoxicity.
authors.affiliation: *Department of Molecular and Clinical Pharmacology, MRC Centre for Drug Safety Science, Sherrington Building, the University of Liverpool, Ashton Street, L69 3GE, UK Safety and ADME Translational Sciences, AstraZeneca R&D, Cambridge, CB4 0WG, UK.
authors.forename: Stephanie M
authors.initials: SM
authors.lastname: Ravenscroft
authors.affiliation: Safety and ADME Translational Sciences, AstraZeneca R&D, Cambridge, CB4 0WG, UK.
authors.forename: Amy
authors.initials: A
authors.lastname: Pointon
authors.affiliation: *Department of Molecular and Clinical Pharmacology, MRC Centre for Drug Safety Science, Sherrington Building, the University of Liverpool, Ashton Street, L69 3GE, UK.
authors.forename: Awel W
authors.initials: AW
authors.lastname: Williams
authors.affiliation: *Department of Molecular and Clinical Pharmacology, MRC Centre for Drug Safety Science, Sherrington Building, the University of Liverpool, Ashton Street, L69 3GE, UK Safety and ADME Translational Sciences, AstraZeneca R&D, Cambridge, CB4 0WG, UK m.j.cross@liv.ac.uk.
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Cross
authors.affiliation: *Department of Molecular and Clinical Pharmacology, MRC Centre for Drug Safety Science, Sherrington Building, the University of Liverpool, Ashton Street, L69 3GE, UK Safety and ADME Translational Sciences, AstraZeneca R&D, Cambridge, CB4 0WG, UK Safety and ADME Translational Sciences, AstraZeneca R&D, Cambridge, CB4 0WG, UK.
authors.forename: James E
authors.initials: JE
authors.lastname: Sidaway
mesh_terms: D020013:Calcium Signaling / Q000187:drug effects; D002304:Cardiac Pacing, Artificial; D002316:Cardiotonic Agents / Q000494:pharmacology*; D002450:Cell Communication; D002478:Cells, Cultured; D018920:Coculture Techniques; D004305:Dose-Response Relationship, Drug; D042783:Endothelial Cells / Q000187:drug effects* / Q000378:metabolism; D005347:Fibroblasts / Q000187:drug effects* / Q000378:metabolism; D000066449:Human Embryonic Stem Cells / Q000187:drug effects* / Q000378:metabolism; D006801:Humans; D057026:Induced Pluripotent Stem Cells / Q000187:drug effects* / Q000378:metabolism; D009200:Myocardial Contraction / Q000187:drug effects*; D032383:Myocytes, Cardiac / Q000187:drug effects* / Q000378:metabolism; D010641:Phenotype; D009418:S100 Proteins / Q000378:metabolism; D018874:Spheroids, Cellular; D013997:Time Factors
chemical_list: D002316:Cardiotonic Agents; D009418:S100 Proteins; C110294:S100A1 protein
keywords: S100A1; cardiac microtissue; cardiotoxicity; contractility; hESC-CMs; inotropy