title: Species-specific regulation of fibrinogen synthesis with implications for porcine hepatocyte xenotransplantation.
abstract: BACKGROUND
  Patients with liver failure could potentially be bridged with porcine xenogeneic liver cell transplantation. We examined species-specific differences between primary human and porcine hepatocytes in the regulation of coagulation protein expression and function.
  
  
  METHODS
  Isolated primary human and porcine hepatocytes were stimulated with either porcine or human interleukin (IL)-6 (10 ng/ml), IL-1β (10 ng/ml), and tumor necrosis factor-alpha (TNF-α, 30 ng/ml). mRNA expression of coagulation factors were measured by RT-PCR and real-time PCR. Cell culture supernatants were used for the measurement of fibrinogen by ELISA and determination of fibrin clot generation.
  
  
  RESULTS
  Fibrinogen expression in human hepatocytes increased after IL-6 treatment (P = 0.010) and decreased after TNF-α treatment (P = 0.005). Porcine hepatocytes displayed a lower increase in fibrinogen expression after IL-6 treatment as compared to hepatocytes of human origin (P = 0.021). Porcine hepatocytes responded contrarily following TNF-α treatment with an increased expression of fibrinogen resulting in a significant species-specific difference between human and porcine hepatocytes (P = 0.029). Fibrin polymer generation by human hepatocytes was stable and widely branched after IL-6 treatment, while stimulation with TNF-α displayed no fibrin generation at all. In contrast, treatment of porcine hepatocytes with TNF-α resulted in generation of a stable and widely branched fibrin polymer, and stimulation with IL-6 only leads to generation of partial fibrin aggregates.
  
  
  CONCLUSIONS
  We identified species-specific differences in the regulation of fibrinogen mRNA expression and fibrin generation under inflammatory stimuli. In hepatic xenotransplantation of porcine origin, these interspecies differences might lead to a loss of physiological coagulation function and a loss of transplanted cells.
authors.affiliation: Department of General, Visceral and Transplant Surgery, Hannover Medical School, Hannover, Germany; Integrated Research and Treatment Center Transplantation (IFB-Tx), Hannover Medical School, Hannover, Germany.
authors.forename: Wolf
authors.initials: W
authors.lastname: Ramackers
authors.forename: Johannes
authors.initials: J
authors.lastname: Klose
authors.forename: Florian W R
authors.initials: FW
authors.lastname: Vondran
authors.forename: Harald
authors.initials: H
authors.lastname: Schrem
authors.forename: Alexander
authors.initials: A
authors.lastname: Kaltenborn
authors.forename: Jürgen
authors.initials: J
authors.lastname: Klempnauer
authors.forename: Moritz
authors.initials: M
authors.lastname: Kleine
mesh_terms: D000818:Animals; D015415:Biomarkers / Q000378:metabolism; D004797:Enzyme-Linked Immunosorbent Assay; D005340:Fibrinogen / Q000378:metabolism*; D022781:Hepatocytes / Q000378:metabolism / Q000637:transplantation*; D006801:Humans; D053583:Interleukin-1beta / Q000378:metabolism; D015850:Interleukin-6 / Q000378:metabolism; D060888:Real-Time Polymerase Chain Reaction; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013552:Swine; D014183:Transplantation, Heterologous / Q000379:methods*; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism
chemical_list: D015415:Biomarkers; D053583:Interleukin-1beta; D015850:Interleukin-6; D014409:Tumor Necrosis Factor-alpha; D005340:Fibrinogen
keywords: IL-1β; IL-6; TNF-α; acute phase reaction; hepatocyte transplantation; human cytokines; species-specific gene regulation