title: Developmental origin of postnatal cardiomyogenic progenitor cells.
abstract: OBJECTIVE
  To trace the cell origin of the cells involved in postnatal cardiomyogenesis.
  
  
  METHODS
  Nkx2.5 enhancer-eGFP (Nkx2.5 enh-eGFP) mice were used to test the cardiomyogenic potential of Nkx2.5 enhancer-expressing cells. By analyzing Cre excision of activated Nkx2.5-eGFP+ cells from different lineage-Cre/Nkx2.5 enh-eGFP/ROSA26 reporter mice, we traced the developmental origin of Nkx2.5 enhancer-expressing cells.
  
  
  RESULTS
  Nkx2.5 enhancer-expressing cells could differentiate into striated cardiomyocytes bothin vitroandin vivo. Nkx2.5-eGFP+ cells increased remarkably after experimental myocardial infarction (MI). The post-MI Nkx2.5-eGFP+ cells originated from the embryonic epicardial cells, not from the pre-existing cardiomyocytes, endothelial cells, cardiac neural crest cells or perinatal/postnatal epicardial cells.
  
  
  CONCLUSIONS
  Postnatal Nkx2.5 enhancer-expressing cells are cardiomyogenic progenitor cells and originate from embryonic epicardium-derived cells.
authors.affiliation: Section of Cardiology, Cardiovascular Center, Far Eastern Memorial Hospital, Pan Chiao, New Taipei City, Taiwan; Graduate Institute of Clinical Medicine, College of Medicine, National Taiwan University, Taiwan; College of Informatics, Yuan Ze University, Chungli, Taoyuan, Taiwan; Section of Cardiology, Cardiovascular Center, Far Eastern Memorial Hospital, Pan Chiao, New Taipei City, Taiwan; Graduate Institute of Clinical Medicine, College of Medicine, National Taiwan University, Taiwan; College of Informatics, Yuan Ze University, Chungli, Taoyuan, Taiwan.
authors.forename: Yuan-Hung
authors.initials: YH
authors.lastname: Liu
authors.affiliation: Department of Internal Medicine, National Taiwan University Hospital, Taipei, Taiwan; Department of Internal Medicine, National Taiwan University Hospital, Taipei, Taiwan.
authors.forename: Ling-Ping
authors.initials: LP
authors.lastname: Lai
authors.affiliation: Section of Cardiology, Cardiovascular Center, Far Eastern Memorial Hospital, Pan Chiao, New Taipei City, Taiwan; Section of Cardiology, Cardiovascular Center, Far Eastern Memorial Hospital, Pan Chiao, New Taipei City, Taiwan.
authors.forename: Shih-Yun
authors.initials: SY
authors.lastname: Huang
authors.affiliation: Section of Cardiology, Cardiovascular Center, Far Eastern Memorial Hospital, Pan Chiao, New Taipei City, Taiwan; Section of Cardiology, Cardiovascular Center, Far Eastern Memorial Hospital, Pan Chiao, New Taipei City, Taiwan.
authors.forename: Yi-Shuan
authors.initials: YS
authors.lastname: Lin
authors.affiliation: Department of Animal Science & Technology, National Taiwan University, Taipei, Taiwan; Department of Animal Science & Technology, National Taiwan University, Taipei, Taiwan.
authors.forename: Shinn-Chih
authors.initials: SC
authors.lastname: Wu
authors.affiliation: Department of Animal Science & Technology, National Taiwan University, Taipei, Taiwan; Department of Animal Science & Technology, National Taiwan University, Taipei, Taiwan.
authors.forename: Chih-Jen
authors.initials: CJ
authors.lastname: Chou
authors.affiliation: Department of Internal Medicine, National Taiwan University Hospital, Taipei, Taiwan; Department of Internal Medicine, National Taiwan University Hospital, Taipei, Taiwan.
authors.forename: Jiunn-Lee
authors.initials: JL
authors.lastname: Lin
keywords: Nkx2.5; cardiac progenitor cells; cardiac regeneration; epicardium-derived cells; myocardial infarction