Construction of vascularized cardiac tissue from genetically modified mouse embryonic stem cells.
BACKGROUND
The aim of myocardial tissue engineering is to repair or regenerate damaged myocardium with engineered cardiac tissue constructed by a combination of cells and scaffolds in vitro. However, this strategy has been hampered by the lack of cardiomyocytes and the significant cell death after transplantation in vivo.


METHODS
In this study we explored the feasibility of in vitro construction of vascularized cardiac muscle using genetically modified mouse embryonic stem cells (ESCs) transfected by pMHC-neo/SV40-hygro. A stirred bioreactor was used to facilitate the formation of a large number of ESC-derived cardiomyocytes, which were then mixed with human umbilical vein endothelial cells (HUVECs) and mouse embryonic fibroblasts (MEFs) in a liquid collagen scaffold to construct highly vascularized cardiac tissue in vitro.


RESULTS
The resulting tissue constructs were transplanted into dorsal subcutaneous sites of nude mice. Tumor formation was not detected in all samples and vascularized cardiac tissue could survive after transplantation. Vascularization of the implanted cardiac muscle was significantly enhanced by the addition of HUVECs and MEFs, which resulted in a thicker myocardium. The combination of genetically modified ESCs and stirred bioreactor cultivation not only benefited the large-scale production of pure ESC-derived cardiomyocytes, but also effectively controlled the potential risk of undifferentiated ESCs.


CONCLUSIONS
Using liquid collagen as scaffold, the enriched cardiomyocytes derived from genetically modified ESCs mixed with HUVECs and MEFs in 3-dimensional culture resulted in highly vascularized cardiac tissues.
Department of Cell Engineering, Institute of Biotechnology, Academy of Military Medical Sciences, Beijing, China.
Wenjun
W
He
Lingling
L
Ye
Shichong
S
Li
Hong
H
Liu
Benchuan
B
Wu
Qiwei
Q
Wang
Xiaobing
X
Fu
Weidong
W
Han
Zhaolie
Z
Chen
D000818:Animals; D018929:Cell Culture Techniques; D002460:Cell Line; D017690:Cell Transplantation; D053595:Embryonic Stem Cells / Q000502:physiology*; D005240:Feasibility Studies; D005347:Fibroblasts; D005818:Genetic Engineering; D061307:Human Umbilical Vein Endothelial Cells; D006801:Humans; D051379:Mice; D008819:Mice, Nude; D032383:Myocytes, Cardiac / Q000502:physiology*; D018919:Neovascularization, Physiologic / Q000502:physiology*; D023822:Tissue Engineering / Q000379:methods*; D014162:Transfection