title: Prion Protein and Stage Specific Embryo Antigen 1 as Selection Markers to Enrich the Fraction of Murine Embryonic Stem Cell-Derived Cardiomyocytes.
abstract: BACKGROUND
  The prion protein (PrP) might be useful as a tool to collect cardiac progenitor cells derived from embryonic stem (ES) cells. It is also possible that PrP(+) cells include undifferentiated cells with a capacity to develop into tumors.
  
  
  METHODS
  PrP(+) cells isolated from embryoid bodies (EB) formed by mouse AB1 ES cells were examined using RT-PCR analysis and clonogeneic cell assay. To assess their potential to differentiate into cardiomyocytes, Nkx2.5(GFP/+) (hcgp7) cells, another ES cell line that carries the GFP reporter gene in the Nkx2.5 loci, were used.
  
  
  RESULTS
  PrP(+) cells isolated from EB of day 7 and 14 did not express pluripotency markers, but expressed cardiac cell markers, while PrP(+) cells isolated from EB of day 21 expressed pluripotency markers. Cultured PrP(+) cells isolated from EB of day 21 expressed pluripotency markers to form colonies, whereas those isolated from EB of day 7 and 14 did not. To exclude proliferating cells from PrP(+) cells, stage specific embryo antigen 1 (SSEA1) was employed as a second marker. PrP(+)/SSEA1(-) cells did not proliferate and expressed cardiac cell markers, while PrP(+)/SSEA1(+) did proliferate.
  
  
  CONCLUSIONS
  PrP(+) cells isolated from EB included undifferentiated cells in day 21. PrP(+)/SSEA1(-) cells included cardiomyoctes, suggesting PrP and SSEA1 may be useful as markers to enrich the fraction of cardiomyocytes.
authors: Division of Regenerative Medicine and Therapeutics, Department of Genetic Medicine and Regenerative Therapeutics, Tottori University Graduate School of Medical Science, Yonago, 683-8503, Japan.
authors: Nobuhito
authors: N
authors: Ikeda
authors: †Division of Functional Genomics, Research Center for Bioscience and Technology, Tottori University, Yonago, 683-8503, Japan.
authors: Yuji
authors: Y
authors: Nakayama
authors: Division of Regenerative Medicine and Therapeutics, Department of Genetic Medicine and Regenerative Therapeutics, Tottori University Graduate School of Medical Science, Yonago, 683-8503, Japan.
authors: Natsumi
authors: N
authors: Nakazawa
authors: Division of Regenerative Medicine and Therapeutics, Department of Genetic Medicine and Regenerative Therapeutics, Tottori University Graduate School of Medical Science, Yonago, 683-8503, Japan.
authors: Akio
authors: A
authors: Yoshida
authors: ‡Department of Biological Regulation, School of Health Sciences, Tottori University Faculty of Medicine, Yonago, 683-8503, Japan.
authors: Haruaki
authors: H
authors: Ninomiya
authors: Division of Regenerative Medicine and Therapeutics, Department of Genetic Medicine and Regenerative Therapeutics, Tottori University Graduate School of Medical Science, Yonago, 683-8503, Japan.
authors: Yasuaki
authors: Y
authors: Shirayoshi
keywords: cell differentiation; embryonic stem cells; prion protein; stage-specific embryonic antigens