Differentiation of human embryonic stem cells to cardiomyocytes: role of coculture with visceral endoderm-like cells.
BACKGROUND
Cardiomyocytes derived from human embryonic stem (hES) cells could be useful in restoring heart function after myocardial infarction or in heart failure. Here, we induced cardiomyocyte differentiation of hES cells by a novel method and compared their electrophysiological properties and coupling with those of primary human fetal cardiomyocytes.


RESULTS
hES cells were cocultured with visceral-endoderm (VE)-like cells from the mouse. This initiated differentiation to beating muscle. Sarcomeric marker proteins, chronotropic responses, and ion channel expression and function were typical of cardiomyocytes. Electrophysiology demonstrated that most cells resembled human fetal ventricular cells. Real-time intracellular calcium measurements, Lucifer yellow injection, and connexin 43 expression demonstrated that fetal and hES-derived cardiomyocytes are coupled by gap junctions in culture. Inhibition of electrical responses by verapamil demonstrated the presence of functional alpha1c-calcium ion channels.


CONCLUSIONS
This is the first demonstration of induction of cardiomyocyte differentiation in hES cells that do not undergo spontaneous cardiogenesis. It provides a model for the study of human cardiomyocytes in culture and could be a step forward in the development of cardiomyocyte transplantation therapies.
Mummery
Christine
C
Hubrecht Laboratory, University Medical Center Utrecht, Utrecht, The Netherlands. christin@niob.knaw.nl
Ward-van Oostwaard
Dorien
D
Doevendans
Pieter
P
Spijker
Rene
R
van den Brink
Stieneke
S
Hassink
Rutger
R
van der Heyden
Marcel
M
Opthof
Tobias
T
Pera
Martin
M
de la Riviere
Aart Brutel
AB
Passier
Robert
R
Tertoolen
Leon
L
D000200:Action Potentials / Q000502:physiology; D000818:Animals; D000943:Antigens, Differentiation / Q000096:biosynthesis; D020013:Calcium Signaling / Q000502:physiology; D002450:Cell Communication; D002454:Cell Differentiation / Q000502:physiology*; D002460:Cell Line; D019070:Cell Lineage; D018920:Coculture Techniques; D004707:Endoderm / Q000166:cytology*; D005456:Fluorescent Dyes; D006321:Heart / Q000196:embryology; D006801:Humans; D007473:Ion Channels / Q000096:biosynthesis; D051379:Mice; D009206:Myocardium / Q000166:cytology; D032383:Myocytes, Cardiac / Q000166:cytology* / Q000502:physiology; D018408:Patch-Clamp Techniques; D013234:Stem Cells / Q000166:cytology*; D014781:Viscera / Q000166:cytology*
D000943:Antigens, Differentiation; D005456:Fluorescent Dyes; D007473:Ion Channels