title: Modification of a purification and expansion method for human embryonic stem cell-derived cardiomyocytes.
abstract: OBJECTIVE
  This study aimed to develop a simple and efficient purification method for human embryonic stem cell (hESC)-derived cardiomyocytes (CMs) using a low-glucose culture system. In addition, we investigated whether intercellular adhesion between single hESC-CMs plays a critical role in enhancing proliferation of purified hESC-CMs.
  
  
  METHODS
  hESCs were cultured in suspension to form human embryoid bodies (hEBs) from which ∼15% contracting clusters were derived after 15-20 days in culture. To purify CMs from contracting hEBs, we first manually isolated contracting clumps that were re-cultured on gelatin-coated plates with media containing a low concentration of glucose. The purified hESC-CMs were cultured at different densities to examine whether cell-cell contact enhances proliferation of hESC-CMs.
  
  
  RESULTS
  Purified CMs demonstrated spontaneous contraction and strongly expressed the CM-specific markers cardiac troponin T and slow myosin heavy chain. We investigated the purification efficiency by examining the expression levels of cardiac-related genes and the expression of MitoTracker Red dye. In addition, purified hESC-CMs in low-glucose culture demonstrated a 1.5-fold increase in their proliferative capacity compared to those cultured as single hESC-CMs.
  
  
  CONCLUSIONS
  A low level of glucose is efficient in purifying hESC-CMs and intercellular adhesion between individual hESC-CMs plays a critical role in enhancing hESC-CM proliferation.
authors: Stem Cell Research Laboratory, CHA Stem Cell Institute, CHA University, Seol 135-081, Korea.
authors: Soon-Jung
authors: SJ
authors: Park
authors: Daekyeong
authors: D
authors: Bae
authors: Sung-Hwan
authors: SH
authors: Moon
authors: Hyung-Min
authors: HM
authors: Chung
mesh_terms: D018929:Cell Culture Techniques / Q000379:methods*; D002454:Cell Differentiation / Q000187:drug effects; D049109:Cell Proliferation / Q000187:drug effects; D002469:Cell Separation / Q000379:methods; D003470:Culture Media / Q000494:pharmacology*; D053595:Embryonic Stem Cells / Q000166:cytology* / Q000187:drug effects; D005947:Glucose / Q000494:pharmacology*; D006801:Humans; D057026:Induced Pluripotent Stem Cells / Q000166:cytology; D032383:Myocytes, Cardiac / Q000166:cytology* / Q000187:drug effects; D020133:Reverse Transcriptase Polymerase Chain Reaction
chemical_list: D003470:Culture Media; D005947:Glucose