title: Pharmacogenetic selection of transplanted human hepatocytes in immunocompetent rats.
abstract: OBJECTIVE
  To introduce a genetic survival advantage for transplanted human hepatocytes over host cells in rats.
  
  
  METHODS
  Green fluorescent protein (GFP) was introduced into Huh-7 human hepatoma cells to create fluorescent GFP-Huh-7 cells. mRNA of CYP2E1, the enzyme that converts acetaminophen (APA) into hepatotoxic intermediates, was quantified by real-time polymerase chain reaction (PCR). The effects of APA on GFP-Huh-7 and control Huh-7 cells were determined in a cell culture. Immunological tolerance was induced by the injection of GFP-Huh-7 cells into fetal rats in utero. The GFP-Huh-7 cells were transplanted after birth of the rats into tolerant rats followed by APA treatment. Serum alanine aminotransferase (ALT) levels and liver histological data were obtained. GFP-Huh-7 cells were detected by quantitive PCR and microscopy.
  
  
  RESULTS
  CYP2E1 mRNA levels in the GFP-Huh-7 cells were 2.7% of parental Huh-7 cells. In 1 mmol/L APA, parental Huh-7 cells decreased by 60% while GFP-Huh-7 cells increased to within 95% of untreated controls after 5 days. In rats in which GFP-Huh-7 cells were transplanted and treated with APA, serum ALT increased to a peak of 200 U/L on day 1 and returned to normal levels by day 3. Fluorescence microscopy of liver specimens from rats transplanted with GFP-Huh-7 cells showed substantial increases in GFP-Huh-7, but not Huh-7 cells by day 7 after APA treatment. Real-time PCR confirmed a 10-fold increase of GFP mRNA in APA-treated rats, but not in those without APA treatment.
  
  
  CONCLUSIONS
  The difference in CYP2E1 gene expression between GFP-Huh-7 and rat hepatocytes provides a convenient means for the enrichment of transplanted human cells in rat liver.
authors.affiliation: Department of Medicine, Division of Gastroenterology-Hepatology, University of Connecticut Health Center, Farmington, Connecticut 06030-1845, USA.
authors.forename: Martina
authors.initials: M
authors.lastname: Smolic
authors.forename: Catherine H
authors.initials: CH
authors.lastname: Wu
authors.forename: Shilpa
authors.initials: S
authors.lastname: Madadi
authors.forename: Nidhi
authors.initials: N
authors.lastname: Gupta
authors.forename: Robert
authors.initials: R
authors.lastname: Smolic
authors.forename: Marcy
authors.initials: M
authors.lastname: Coash
authors.forename: Jeanette
authors.initials: J
authors.lastname: Smith
authors.forename: George Y
authors.initials: GY
authors.lastname: Wu
mesh_terms: D000082:Acetaminophen / Q000494:pharmacology*; D000410:Alanine Transaminase / Q000097:blood; D018712:Analgesics, Non-Narcotic / Q000494:pharmacology; D000818:Animals; D006528:Carcinoma, Hepatocellular; D019392:Cytochrome P-450 CYP2E1 / Q000235:genetics / Q000378:metabolism; D004195:Disease Models, Animal; D005260:Female; D015870:Gene Expression / Q000187:drug effects*; D006085:Graft Survival / Q000502:physiology*; D049452:Green Fluorescent Proteins / Q000235:genetics; D056945:Hep G2 Cells; D022781:Hepatocytes / Q000187:drug effects / Q000502:physiology / Q000637:transplantation*; D006801:Humans; D007108:Immune Tolerance / Q000502:physiology*; D007121:Immunocompetence / Q000502:physiology*; D008113:Liver Neoplasms; D009368:Neoplasm Transplantation; D011247:Pregnancy; D051381:Rats; D017207:Rats, Sprague-Dawley; D014183:Transplantation, Heterologous
chemical_list: D018712:Analgesics, Non-Narcotic; D049452:Green Fluorescent Proteins; D000082:Acetaminophen; D019392:Cytochrome P-450 CYP2E1; D000410:Alanine Transaminase