Replating of Human Pluripotent Stem Cell Derived Cardiomyocytes Induces a Shift in Myosin Heavy Chain Expression and Changes in Contractile Function

Human embryonic stem cell-derived cardiomyocytes (hESC-CMs) and human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) grown for 35 days on laminin-coated coverslips, a stiff matrix, were enzymatically dissociated, replated on laminin-coated coverslips and grown for further 2 days. Gene expression was compared with controls grown for 37 days on laminin-coated coverslips. Total RNA was isolated and gene expression was analyzed by RNA-sequencing (RNA-seq) on an Illumina NextSeq 550 sequencer using a High Output Flowcell for single reads (20024906; Illumina). Gene enrichment analysis based on RNA-Seq data of hESC-CMs replated for 2 days as compared with 37 days old controls was performed by using the comprehensive gene set enrichment analysis tool Enrichr for pathway analysis with KEGG Pathways 2019 Human, as well as for Gene Ontology (GO) analysis with GO Cellular Component 2018, GO Molecular Function 2018, and GO Biological Process 2018. Gene enrichment was also analyzed by Ingenuity Pathway analysis (IPA, Qiagen), especially Canonical Pathways analysis. Gene enrichment analysis revealed changes in the gene expression profile, especially of mechanosensation/-transduction-related genes and pathways in replated hESC-CMs. Gene enrichment analysis based on RNA-Seq data from hESC-CMs replated on day 35 and cultivated for 2 more days versus hES-CMs cultivated for 37 days