title: Generation of electrophysiologically functional cardiomyocytes from mouse induced pluripotent stem cells.
abstract: Induced pluripotent stem (iPS) cells can efficiently differentiate into the three germ layers similar to those formed by differentiated embryonic stem (ES) cells. This provides a new source of cells in which to establish preclinical allogeneic transplantation models. Our iPS cells were generated from mouse embryonic fibroblasts (MEFs) transfected with the Yamanaka factors, the four transcription factors (Oct4, Sox2, Klf4 and c-Myc), without antibiotic selection or MEF feeders. After the formation of embryoid bodies (EBs), iPS cells spontaneously differentiated into Flk1-positive cardiac progenitors and cardiomyocytes expressing cardiac-specific markers such as alpha sarcomeric actinin (α-actinin), cardiac alpha myosin heavy chain (α-MHC), cardiac troponin T (cTnT), and connexin 43 (CX43), as well as cardiac transcription factors Nk2 homebox 5 (Nkx2.5) and gata binding protein 4 (gata4). The electrophysiological activity of iPS cell-derived cardiomyocytes (iPS-CMs) was detected in beating cell clusters with optical mapping and RH237 a voltage-sensitive dye, and in single contracting cells with patch-clamp technology. Incompletely differentiated iPS cells formed teratomas when transplanted into a severe combined immunodeficiency (SCID) mouse model of myocardial infarction. Our results show that somatic cells can be reprogrammed into pluripotent stem cells, which in turn spontaneously differentiate into electrophysiologically functional mature cardiomyocytes expressing cardiac-specific makers, and that these cells can potentially be used to repair myocardial infarction (MI) in the future.
authors.affiliation: Department of Pediatrics, Dell Pediatric Research Institute, University of Texas at Austin Dell Medical School, 1400 Barbara Jordan Blvd., Austin, TX 78723, USA.
authors.forename: Hongran
authors.initials: H
authors.lastname: Wang
authors.affiliation: Electrophysiology Research Laboratory, Texas Heart Institute, Houston, TX 77030, USA.
authors.forename: Yutao
authors.initials: Y
authors.lastname: Xi
authors.affiliation: Department of Internal Medicine, University of Nevada School of Medicine, Reno, NV 89557, USA.
authors.forename: Yi
authors.initials: Y
authors.lastname: Zheng
authors.affiliation: Stem Cell Center, Texas Heart Institute, Houston, TX 77030, USA.
authors.forename: Xiaohong
authors.initials: X
authors.lastname: Wang
authors.affiliation: Department of Pediatrics, Dell Pediatric Research Institute, University of Texas at Austin Dell Medical School, 1400 Barbara Jordan Blvd., Austin, TX 78723, USA. Electronic address: austin.cooney@austin.utexas.edu.
authors.forename: Austin J
authors.initials: AJ
authors.lastname: Cooney
mesh_terms: D000818:Animals; D002454:Cell Differentiation; D002460:Cell Line; D065150:Cellular Reprogramming; D018031:Connexin 43 / Q000378:metabolism; D004195:Disease Models, Animal; D005347:Fibroblasts / Q000166:cytology; D005434:Flow Cytometry; D057026:Induced Pluripotent Stem Cells / Q000166:cytology*; D000090062:Kruppel-Like Factor 4; D051379:Mice; D008810:Mice, Inbred C57BL; D016513:Mice, SCID; D008856:Microscopy, Fluorescence; D009203:Myocardial Infarction / Q000628:therapy; D032383:Myocytes, Cardiac / Q000166:cytology* / Q000378:metabolism / Q000637:transplantation; D018995:Myosin Heavy Chains / Q000378:metabolism; D018408:Patch-Clamp Techniques; D013724:Teratoma / Q000378:metabolism / Q000473:pathology; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism; D014184:Transplantation, Homologous; D020107:Troponin T / Q000378:metabolism
chemical_list: D018031:Connexin 43; C000715468:Klf4 protein, mouse; D000090062:Kruppel-Like Factor 4; D014157:Transcription Factors; D020107:Troponin T; D018995:Myosin Heavy Chains