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Long-term self-renewing human epicardial cells generated from pluripotent stem cells under defined xeno-free conditions

Nature Biomedical Engineering volume 1, Article number: 0003 (2016) | Download Citation


The epicardium contributes both multi-lineage descendants and paracrine factors to the heart during cardiogenesis and cardiac repair, underscoring its potential for use in cardiac regenerative medicine. Yet little is known about the cellular and molecular mechanisms that regulate human epicardial development and regeneration. Here, we show that the temporal modulation of canonical Wnt signalling is sufficient for epicardial induction from six different human pluripotent stem cell (hPSC) lines, including a WT1-2A-eGFP knock-in reporter line, under chemically defined, xeno-free conditions. We also show that treatment with transforming growth factor beta (TGF-β)-signalling inhibitors permitted long-term expansion of the hPSC-derived epicardial cells, resulting in more than 25 population doublings of WT1+ cells in homogenous monolayers. The hPSC-derived epicardial cells were similar to primary epicardial cells both in vitro and in vivo, as determined by morphological and functional assays, including RNA sequencing. Our findings have implications for the understanding of self-renewal mechanisms of the epicardium and for epicardial regeneration using cellular or small-molecule therapies.

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We thank D.A. Roenneburg and X. Wang for their technical support. We also thank members of the Palecek group for critical discussion of the manuscript. This work was supported by NIH grant EB007534 (S.P.P.), NSF grant 1547225 (S.P.P.), and a fellowship from the University of Wisconsin Stem Cell and Regenerative Medicine Center (X.B.).

Author information


  1. Department of Chemical & Biological Engineering, University of Wisconsin, Madison, Wisconsin 53706, USA

    • Xiaoping Bao
    • , Xiaojun Lian
    • , Tongcheng Qian
    • , Vijesh J. Bhute
    • , Tianxiao Han
    • , Mengxuan Shi
    •  & Sean P. Palecek
  2. Departments of Biomedical Engineering, Biology and Huck Institutes of the Life Sciences, The Pennsylvania State University, University Park, Pennsylvania 16802, USA

    • Xiaojun Lian
  3. Department of Medicine, University of Wisconsin, Madison, Wisconsin 53706, USA

    • Timothy A. Hacker
    •  & Eric G. Schmuck
  4. Department of Cardiovascular and Metabolic Diseases Innovative Medicine Unit, AstraZeneca, Mölndal, 43183, Sweden

    • Lauren Drowley
    • , Alleyn T. Plowright
    •  & Qing-Dong Wang
  5. Department of Molecular Cell Biology, Leiden University Medical Center, 2333 ZC Leiden, the Netherlands

    • Marie-Jose Goumans


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X.B. and S.P.P. designed this study and prepared the manuscript. X.B. undertook experimentation and data analysis. X.L. contributed to the study design and assisted in writing the manuscript. T.A.H. and E.G.S. designed and performed the in vivo study. T.H., V.J.B., T.Q. and M.S. assisted in differentiation experiments and data analysis. L.D., A.T.P., Q.-D.W. and M.-J.G. isolated and provided the human primary donor samples for RNA-seq. All authors reviewed and approved the manuscript.

Competing interests

The authors declare no competing financial interests.

Corresponding author

Correspondence to Sean P. Palecek.

Supplementary information

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    Supplementary Information

    Supplementary figures and tables, and movie legends.


  1. 1.

    Supplementary Movie 1

    Non-contracting hESC-derived pro-epicardial cells at day 12.

  2. 2.

    Supplementary Movie 2

    Spontaneously contracting hESC-derived cardiomyocytes at day 12.

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    Supplementary Movie 3

    Spontaneously contracting hESC-derived cardiomyocytes at day 12.

  4. 4.

    Supplementary Movie 4

    Non-contracting iPSC-derived pro-epicardial cells at day 12.

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