title: Transplantation of endothelial cells corrects the phenotype in hemophilia A mice.
abstract: BACKGROUND
  The deficiency of factor VIII, a co-factor in the intrinsic coagulation pathway results in hemophilia A. Although FVIII is synthesized largely in the liver, the specific liver cell type(s) responsible for FVIII production is controversial.
  
  
  OBJECTIVE
  This study aimed to determine the cellular origin of FVIII synthesis and release in mouse models.
  
  
  METHODS
  We transplanted cells into the peritoneal cavity of hemophilia A knockout mice. Plasma FVIII activity was measured using a Chromogenix assay 2-7 days after cell transplantation, and phenotypic correction was determined with tail-clip challenge 7 days following cell transplantation. Transplanted cells were identified by histologic and molecular assays.
  
  
  RESULTS
  Untreated hemophilia A mice, as well as mice treated with the hepatocyte-enriched fraction, showed extensive mortality following tail-clip challenge. In contrast, recipients of unfractionated liver cells (mixture of hepatocytes, liver sinusoidal endothelial cells (LSEC), Kupffer cells, and hepatic stellate cells) or of the cell fraction enriched in LSECs survived tail-clip challenge (P < 0.001). FVIII was secreted in the blood stream in recipients of unfractionated liver cells, LSECs and pancreatic islet-derived MILE SVEN 1 (MS1) endothelial cells. Although transplanted hepatocytes maintained functional integrity in the peritoneal cavity, these cells did not produce detectable plasma FVIII activity.
  
  
  CONCLUSIONS
  The assay of cell transplantation in the peritoneal cavity showed that endothelial cells but not hepatocytes produced phenotypic correction in hemophilia A mice. Therefore, endothelial cells should be suitable additional targets for cell and gene therapy in hemophilia A.
authors.affiliation: Marion Bessin Liver Research Center, Departments of Medicine and Pathology, Albert Einstein College of Medicine, Bronx, NY 10461, USA.
authors.forename: V
authors.initials: V
authors.lastname: Kumaran
authors.forename: D
authors.initials: D
authors.lastname: Benten
authors.forename: A
authors.initials: A
authors.lastname: Follenzi
authors.forename: B
authors.initials: B
authors.lastname: Joseph
authors.forename: R
authors.initials: R
authors.lastname: Sarkar
authors.forename: S
authors.initials: S
authors.lastname: Gupta
mesh_terms: D000818:Animals; D017690:Cell Transplantation; D042783:Endothelial Cells / Q000378:metabolism / Q000637:transplantation*; D005169:Factor VIII / Q000008:administration & dosage / Q000096:biosynthesis*; D006085:Graft Survival; D006467:Hemophilia A / Q000628:therapy*; D022781:Hepatocytes / Q000637:transplantation; D008099:Liver / Q000166:cytology* / Q000378:metabolism; D051379:Mice; D018345:Mice, Knockout
chemical_list: D005169:Factor VIII