title: The influence of donor age on liver regeneration and hepatic progenitor cell populations.
abstract: BACKGROUND
  Recent reports suggest that donor age might have a major impact on recipient outcome in adult living donor liver transplantation (LDLT), but the reasons underlying this effect remain unclear. The aims of this study were to compare liver regeneration between young and aged living donors and to evaluate the number of Thy-1+ cells, which have been reported to be human hepatic progenitor cells.
  
  
  METHODS
  LDLT donors were divided into 2 groups (Group O, donor age ≥ 50 years, n = 6 and Group Y, donor age ≤ 30 years, n = 9). The remnant liver regeneration rates were calculated on the basis of computed tomography volumetry on postoperative days 7 and 30. Liver tissue samples were obtained from donors undergoing routine liver biopsy or patients undergoing partial hepatectomy for metastatic liver tumors. Thy-1+ cells were isolated and counted using immunomagnetic activated cell sorting (MACS) technique.
  
  
  RESULTS
  Donor liver regeneration rates were significantly higher in young donors compared to old donors (P = .042) on postoperative day 7. Regeneration rates were significantly higher after right lobe resection compared to rates after left lobe resection. The MACS findings showed that the number of Thy-1+ cells in the human liver consistently tended to decline with age.
  
  
  CONCLUSIONS
  Our study revealed that liver regeneration is impaired with age after donor hepatectomy, especially after right lobe resection. The declining hepatic progenitor cell population might be one of the reasons for impaired liver regeneration in aged donors.
authors: Department of Surgery, Keio University School of Medicine, Tokyo, Japan.
authors: Yoshihiro
authors: Y
authors: Ono
authors: Shigeyuki
authors: S
authors: Kawachi
authors: Tetsu
authors: T
authors: Hayashida
authors: Masatoshi
authors: M
authors: Wakui
authors: Minoru
authors: M
authors: Tanabe
authors: Osamu
authors: O
authors: Itano
authors: Hideaki
authors: H
authors: Obara
authors: Masahiro
authors: M
authors: Shinoda
authors: Taizo
authors: T
authors: Hibi
authors: Go
authors: G
authors: Oshima
authors: Noriyuki
authors: N
authors: Tani
authors: Kisyo
authors: K
authors: Mihara
authors: Yuko
authors: Y
authors: Kitagawa
mesh_terms: D000328:Adult; D000367:Age Factors; D005260:Female; D006498:Hepatectomy; D022781:Hepatocytes / Q000166:cytology* / Q000276:immunology; D006801:Humans; D008099:Liver; D008107:Liver Diseases; D008115:Liver Regeneration / Q000502:physiology*; D016031:Liver Transplantation; D019520:Living Donors; D008297:Male; D008875:Middle Aged; D013234:Stem Cells / Q000166:cytology* / Q000276:immunology; D018800:Thy-1 Antigens
chemical_list: D018800:Thy-1 Antigens