Highly enriched cardiomyocytes from human embryonic stem cells.
BACKGROUND
Current efforts to direct differentiation of human embryonic stem cells (hESC) into a particular cell lineage usually lead to a heterogeneous cell population with only a fraction of the desired cell type present. We show the generation of an essentially pure population of human cardiomyocytes from hESC using lineage selection.


METHODS
A construct comprising the murine alpha-myosin heavy chain (alpha-MHC) promoter driving the neomycin-resistance gene was introduced into hES3 cells to generate stable transgenic lines. Transgenic hESC lines were differentiated into cardiomyocytes and subjected to G418 selection. Both G418-selected and non-selected cardiomyocytes were characterized by immunocytochemistry and reverse transcriptase-polymerase chain reaction (RT-PCR) analysis. The teratoma-forming potential of differentiated cells was assessed by injection of about 2 million cells into the hind limb muscle of SCID mice. Results After cardiac differentiation and antibiotic selection in a suspension culture process, more than 99% of the transgenic cells showed immunoreactivity to alpha-MHC and alpha-actinin; this enrichment efficiency was observed for independent transgenic cell lines. Quantitative RT-PCR analysis revealed high levels of enrichment for cardiac-specific messages in the selected population. Importantly, injection of selected cells into six SCID mice resulted in no apparent teratoma formation, in contrast to differentiated but non-selected controls.


CONCLUSIONS
Our results represent a significant step toward scalable production of pure human cardiomyocytes from stable, expandable hESC lines that will facilitate the development of cell therapies, safety pharmacology and drug discovery.
Xu
X Q
XQ
ES Cell International Pte Ltd, Singapore.
Zweigerdt
R
R
Soo
S Y
SY
Ngoh
Z X
ZX
Tham
S C
SC
Wang
S T
ST
Graichen
R
R
Davidson
B
B
Colman
A
A
Sun
W
W
D000818:Animals; D018929:Cell Culture Techniques; D002454:Cell Differentiation; D002460:Cell Line; D019070:Cell Lineage; D004594:Electrophysiology; D053595:Embryonic Stem Cells / Q000166:cytology / Q000502:physiology; D006614:Hindlimb / Q000473:pathology; D006801:Humans; D051379:Mice; D016513:Mice, SCID; D008822:Mice, Transgenic; D032383:Myocytes, Cardiac / Q000166:cytology / Q000502:physiology; D033581:Stem Cell Transplantation; D013724:Teratoma