Z Gastroenterol 2007; 45 - A5_05
DOI: 10.1055/s-2007-967895

Heparanase and hVEGF165, increases early engraftment, intravascular survival and endothelial cell proliferation, of transplanted hepatocyte, in hepatectomized rats

Y Baruch 1, I Boyanjo 1, V Tsiperson 1, Y Axelman 1, J Dudas 2, G Ramadori 2, N Ilan 3, G Shoshany 4, I Vlodavsky 3, E Veitzman 1
  • 1Liver Unit And 4Department of Pediatric Surgery, Rambam Medical Center And The Bruce Rappaport Faculty of Medicine, Technion-Israel Institute of Technology Haifa, Haifa, Israel
  • 2Department of Internal Medicine, Section of Gastroenterology and Endocrinology, Georg-August-University Goettingen, Robert-Koch-Strasse 40, 37075 Goettingen, Germany, Göttingen
  • 3Tumor And Vascular Biology Research Center, The Bruce Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa, Israel
  • 4Department of Pediatric Surgery, Rambam Medical Center And The Bruce Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa, Israel

Heparanase by degradating heparan sulfate proteoglycans has multifunctional effect on cell-cell interaction, cell invasion and angiogenesis. VEGF, a potent angiogenic factor promotes hepatocyte growth, increases vascular permeability and vasodilatation, and may thus accelerate cell engraftment

Aim: The effect of heparanase and hVEGF165, on hepatocyte engraftment after intrasplenic cell transplantation in partially hepatectomized (PHP) rats.

Methods: Female Lewis rats were subjected to 70% PHP and transplanted with male hepatocytes (107 cells/rat), pre- incubated with heparanase (50µl, n=12), or 240ng VEGF165 or saline as control. Engraftment efficiency was evaluated up to 14 days by a semi-quantitative PCR analysis of the SRY region on Y-chromosome and endothelial cells proliferation by PCNA immunohistochemistry. Post transplant intravascular hepatocytes were studied by immunostaining to Hepar–1, VW-factor, Fibronectin, and SMA.

Results: The number of portal radicles filled with hepatocytes in heparanase and VEGF treated rats was higher than in control rats (p<0.05). The transplanted treated hepatocytes appeared in clusters without signs of damage. Hepar–1 immunostaining shows normal staining of these hepatocytes up to 72 hours post transplantation. The number of transplanted cells detected in the liver was significantly higher (p<0.05) in treated animals vs. controls at 24 and 48 hrs. By 14 days the number of cells was similar to the control group. Already by 24 hrs after transplantation the proliferating index of SEC increased over controls (P<0.02). SMA immunostaining at the site of cell adhesion was non continuous without signs of damage.

Conclusions: Heparanase and hVEGF165 increases the long-term presence of transplanted cells within portal radicles, thereby facilitating their engraftment. Hepatocyte can survive in the portal vessels longer than was expected and it seems that the portal radicle is the main site for cell engraftment, explaining the relative low yield of intravascular cell transplantation.