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The progenitor cell dilemma: Cellular and functional heterogeneity in assistance or escalation of liver injury

  • Author Footnotes
    † This author was the recipient of the EASL Young Investigators’ Award 2016.
    Veronika Lukacs-Kornek
    Correspondence
    Corresponding author. Address: Department of Medicine II, Saarland University Medical Center, Homburg, Germany. Tel.: +49 (0)6841 16 23299; fax: +49 (0)6841 16 23267.
    Footnotes
    † This author was the recipient of the EASL Young Investigators’ Award 2016.
    Affiliations
    Department of Medicine II, Saarland University Medical Center, Saarland University, Homburg, Germany
    Search for articles by this author
  • Frank Lammert
    Affiliations
    Department of Medicine II, Saarland University Medical Center, Saarland University, Homburg, Germany
    Search for articles by this author
  • Author Footnotes
    † This author was the recipient of the EASL Young Investigators’ Award 2016.
Published:November 05, 2016DOI:https://doi.org/10.1016/j.jhep.2016.10.033

      Summary

      Liver progenitor cells (LPCs) are quiescent cells that are activated during liver injury and thought to give rise to hepatocytes and cholangiocytes in order to support liver regeneration and tissue restitution. While hepatocytes are capable of self-renewal, during most chronic injuries the proliferative capacity of hepatocytes is inhibited, thus LPCs provide main source for regeneration. Despite extensive lineage tracing studies, their role and involvement in these processes are often controversial. Additionally, increasing evidence suggests that the LPC compartment consists of heterogeneous cell populations that are actively involved in cellular interactions with myeloid and lymphoid cells during regeneration. On the other hand, LPC expansion has been associated with an increased fibrogenic response, raising concerns about the therapeutic use of these cells. This review aims to summarize the current understanding of the identity, the cellular interactions and the key pathways affecting the biology of LPCs. Understanding the regulatory circuits and the specific role of LPCs is especially important as it could provide novel therapeutic platforms for the treatment of liver inflammation, fibrosis and regeneration.

      Keywords

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