title: Creation of engineered cardiac tissue in vitro from mouse embryonic stem cells.
abstract: BACKGROUND
  Embryonic stem (ES) cells can terminally differentiate into all types of somatic cells and are considered a promising source of seed cells for tissue engineering. However, despite recent progress in in vitro differentiation and in vivo transplantation methodologies of ES cells, to date, no one has succeeded in using ES cells in tissue engineering for generation of somatic tissues in vitro for potential transplantation therapy.
  
  
  RESULTS
  ES-D3 cells were cultured in a slow-turning lateral vessel for mass production of embryoid bodies. The embryoid bodies were then induced to differentiate into cardiomyocytes in a medium supplemented with 1% ascorbic acid. The ES cell-derived cardiomyocytes were then enriched by Percoll gradient centrifugation. The enriched cardiomyocytes were mixed with liquid type I collagen supplemented with Matrigel to construct engineered cardiac tissue (ECT). After in vitro stretching for 7 days, the ECT can beat synchronously and respond to physical and pharmaceutical stimulation. Histological, immunohistochemical, and transmission electron microscopic studies further indicate that the ECTs both structurally and functionally resemble neonatal native cardiac muscle. Markers related to undifferentiated ES cell contamination were not found in reverse transcriptase-polymerase chain reaction analysis of the Percoll-enriched cardiomyocytes. No teratoma formation was observed in the ECTs implanted subcutaneously in nude mice for 4 weeks.
  
  
  CONCLUSIONS
  ES cells can be used as a source of seed cells for cardiac tissue engineering. Additional work remains to demonstrate engraftment of the engineered heart tissue in the case of cardiac defects and its functional integrity within the host's remaining healthy cardiac tissue.
authors.affiliation: Department of Tissue Engineering, Beijing Institute of Basic Medical Sciences, Tissue Engineering Research Center, Academy of Military Medical Sciences, Beijing, People's Republic of China.
authors.forename: Xi-Min
authors.initials: XM
authors.lastname: Guo
authors.forename: Yun-Shan
authors.initials: YS
authors.lastname: Zhao
authors.forename: Hai-Xia
authors.initials: HX
authors.lastname: Chang
authors.forename: Chang-Yong
authors.initials: CY
authors.lastname: Wang
authors.forename: Ling-Ling
authors.initials: LL
authors.lastname: E
authors.forename: Xiao-Ai
authors.initials: XA
authors.lastname: Zhang
authors.forename: Cui-Mi
authors.initials: CM
authors.lastname: Duan
authors.forename: Ling-Zhi
authors.initials: LZ
authors.lastname: Dong
authors.forename: Hong
authors.initials: H
authors.lastname: Jiang
authors.forename: Jing
authors.initials: J
authors.lastname: Li
authors.forename: Ying
authors.initials: Y
authors.lastname: Song
authors.forename: Xiangzhong Jerry
authors.initials: XJ
authors.lastname: Yang
mesh_terms: D000818:Animals; D001205:Ascorbic Acid / Q000494:pharmacology; D002454:Cell Differentiation / Q000187:drug effects; D002478:Cells, Cultured / Q000166:cytology / Q000187:drug effects / Q000637:transplantation; D003094:Collagen; D024042:Collagen Type I; D004338:Drug Combinations; D004622:Embryo, Mammalian / Q000166:cytology; D005973:Glutamine / Q000494:pharmacology; D020007:Implants, Experimental; D007797:Laminin; D008623:Mercaptoethanol / Q000494:pharmacology; D051379:Mice; D008819:Mice, Nude; D009200:Myocardial Contraction / Q000187:drug effects; D032383:Myocytes, Cardiac / Q000166:cytology / Q000187:drug effects / Q000502:physiology / Q000637:transplantation*; D009940:Organoids / Q000502:physiology*; D011509:Proteoglycans; D013234:Stem Cells / Q000166:cytology* / Q000187:drug effects; D013314:Stress, Mechanical; D023822:Tissue Engineering / Q000295:instrumentation / Q000379:methods*
chemical_list: D024042:Collagen Type I; D004338:Drug Combinations; D007797:Laminin; D011509:Proteoglycans; D005973:Glutamine; C059485:matrigel; D008623:Mercaptoethanol; D003094:Collagen; D001205:Ascorbic Acid