title: Liver chimerism after allogeneic blood stem cell transplantation.
abstract: Blood stem cells can mature into elements of many different lineages. We investigated the presence and nature of donor-derived (chimeric) cells within the liver after allogeneic stem cell transplantation.
  
  
  METHODS
  Liver biopsy autopsy specimens were examined from nine female patients who had undergone allogeneic bone marrow (n = 6) or peripheral stem cell (n = 3) transplantation from a male donor. To identify the male origin of cells within the liver, in-situ hybridization for Y-chromosomes was performed in conjunction with CD45 staining to identify leucocytes.
  
  
  RESULTS
  Hematopoietic stem cell engraftment was confirmed in all nine recipients. Histologic examination of the liver tissue sections revealed 5.6-fold more Y-chromosome-positive than CD45-positive staining cells (P < .02), indicative of considerable nonleucocytic chimerism. This was particularly observed in patients who had developed graft-versus-host disease.
  
  
  CONCLUSIONS
  Donor-derived cells can be found in liver tissue specimens after allogeneic stem cell transplantation. A considerable fraction of chimeric (donor-derived) cells appeared to be of nonlymphohematopoietic origin. This finding supports the theory of blood stem cells developing into liver cells of mesenchymal origin.
authors.affiliation: Department of Gastroenterology and Hepatology, LUMC, Leiden, The Netherlands.
authors.forename: W R
authors.initials: WR
authors.lastname: ten Hove
authors.forename: H W
authors.initials: HW
authors.lastname: Verspaget
authors.forename: R
authors.initials: R
authors.lastname: Barge
authors.forename: C B
authors.initials: CB
authors.lastname: Lamers
authors.forename: B
authors.initials: B
authors.lastname: van Hoek
mesh_terms: D000818:Animals; D016026:Bone Marrow Transplantation; D005260:Female; D006801:Humans; D008099:Liver / Q000166:cytology* / Q000473:pathology; D023421:Models, Animal; D012189:Retrospective Studies; D033581:Stem Cell Transplantation; D018183:Transplantation Chimera; D014184:Transplantation, Homologous