title: Direct and indirect contribution of human embryonic stem cell-derived hepatocyte-like cells to liver repair in mice.
abstract: OBJECTIVE
  Many studies of embryonic stem cells have investigated direct cell replacement of damaged tissues, but little is known about how donor cell-derived signals affect host tissue regeneration. We investigated the direct and indirect roles of human embryonic stem cell-derived cells in liver repair in mice.
  
  
  METHODS
  To promote the initial differentiation of human embryonic stem cells into mesendoderm, we activated the β-catenin signaling pathway with lithium; cells were then further differentiated into hepatocyte-like cells. The differentiated cells were purified by indocyanine green staining and laser microdissection and characterized by immunostaining, polymerase chain reaction, biochemical function, electron microscopy, and transplantation analyses. To investigate indirect effects of these cells, secreted proteins (secretomes) were analyzed by a label-free quantitative mass spectrometry. Carbon tetrachloride was used to induce acute liver injury in mice; cells or secreted proteins were administered by intrasplenic or intraperitoneal injection, respectively.
  
  
  RESULTS
  The differentiated hepatocyte-like cells had multiple features of normal hepatocytes, engrafted efficiently into mice, and continued to have hepatic features; they promoted proliferation of host hepatocytes and revascularization of injured host liver tissues. Proteomic analysis identified proteins secreted from these cells that might promote host tissue repair. Injection of the secreted proteins into injured livers of mice promoted significant amounts of tissue regeneration without cell grafts.
  
  
  CONCLUSIONS
  Hepatocyte-like cells derived from human embryonic stem cells contribute to recovery of injured liver tissues in mice, not only by cell replacement but also by delivering trophic factors that support endogenous liver regeneration.
authors.affiliation: Laboratory of Stem Cell Biology, Division of Biotechnology, College of Life Sciences and Biotechnology, Korea University, Seoul, Republic of Korea.
authors.forename: Dong-Hun
authors.initials: DH
authors.lastname: Woo
authors.forename: Suel-Kee
authors.initials: SK
authors.lastname: Kim
authors.forename: Hee-Joung
authors.initials: HJ
authors.lastname: Lim
authors.forename: Jeonghoon
authors.initials: J
authors.lastname: Heo
authors.forename: Hyung Soon
authors.initials: HS
authors.lastname: Park
authors.forename: Gum-Yong
authors.initials: GY
authors.lastname: Kang
authors.forename: Sung-Eun
authors.initials: SE
authors.lastname: Kim
authors.forename: Hyun-Ju
authors.initials: HJ
authors.lastname: You
authors.forename: Daniel J
authors.initials: DJ
authors.lastname: Hoeppner
authors.forename: Youngchul
authors.initials: Y
authors.lastname: Kim
authors.forename: Heechung
authors.initials: H
authors.lastname: Kwon
authors.forename: Tae Hyun
authors.initials: TH
authors.lastname: Choi
authors.forename: Joo Hee
authors.initials: JH
authors.lastname: Lee
authors.forename: Su Hee
authors.initials: SH
authors.lastname: Hong
authors.forename: Kang Won
authors.initials: KW
authors.lastname: Song
authors.forename: Eun-Kyung
authors.initials: EK
authors.lastname: Ahn
authors.forename: Josh G
authors.initials: JG
authors.lastname: Chenoweth
authors.forename: Paul J
authors.initials: PJ
authors.lastname: Tesar
authors.forename: Ronald D G
authors.initials: RD
authors.lastname: McKay
authors.forename: Jong-Hoon
authors.initials: JH
authors.lastname: Kim
mesh_terms: D000818:Animals; D015415:Biomarkers / Q000378:metabolism; D002251:Carbon Tetrachloride; D002454:Cell Differentiation / Q000187:drug effects; D049109:Cell Proliferation; D002469:Cell Separation / Q000379:methods; D002478:Cells, Cultured; D056486:Chemical and Drug Induced Liver Injury / Q000378:metabolism / Q000473:pathology / Q000601:surgery*; D018920:Coculture Techniques; D004195:Disease Models, Animal; D053595:Embryonic Stem Cells / Q000187:drug effects / Q000378:metabolism / Q000637:transplantation*; D022781:Hepatocytes / Q000187:drug effects / Q000378:metabolism / Q000473:pathology / Q000637:transplantation*; D006801:Humans; D007150:Immunohistochemistry; D057026:Induced Pluripotent Stem Cells / Q000187:drug effects / Q000378:metabolism / Q000637:transplantation*; D061346:Laser Capture Microdissection; D018021:Lithium Chloride / Q000494:pharmacology; D008099:Liver / Q000098:blood supply / Q000378:metabolism / Q000473:pathology*; D008115:Liver Regeneration; D013058:Mass Spectrometry; D051379:Mice; D008807:Mice, Inbred BALB C; D008819:Mice, Nude; D008854:Microscopy, Electron; D018919:Neovascularization, Physiologic; D016133:Polymerase Chain Reaction; D040901:Proteomics / Q000379:methods; D013997:Time Factors; D014945:Wound Healing
chemical_list: D015415:Biomarkers; D002251:Carbon Tetrachloride; D018021:Lithium Chloride