Co-Authors:
Yeikilis, R., Department of Anatomy and Cell Biology, The Bruce Rappaport Faculty of Medicine, Rappaport Family Institute for Research in the Medical Sciences, POB 9649, Technion, Haifa 31096, Israel
Gal, S., Department of Anatomy and Cell Biology, The Bruce Rappaport Faculty of Medicine, Rappaport Family Institute for Research in the Medical Sciences, POB 9649, Technion, Haifa 31096, Israel
Kopeiko, N., Department of Experimental Surgery, The Bruce Rappaport Faculty of Medicine, Rappaport Family Institute for Research in the Medical Sciences, POB 9649, Technion, Haifa 31096, Israel
Paizi, M., Department of Anatomy and Cell Biology, The Bruce Rappaport Faculty of Medicine, Rappaport Family Institute for Research in the Medical Sciences, POB 9649, Technion, Haifa 31096, Israel
Pines, M., Institute of Animal Sciences, Agricultural Research Organization, Volcani Center, Bet Dagan 50250, Israel
Braet, F., Australian Key Centre for Microscopy and Microanalysis, The University of Sydney, Sydney, NSW 2006, Australia
Spira, G., Department of Anatomy and Cell Biology, The Bruce Rappaport Faculty of Medicine, Rappaport Family Institute for Research in the Medical Sciences, POB 9649, Technion, Haifa 31096, Israel
Abstract:
Aim: Hydrodynamics based transfection (HBT), the injection of a large volume of naked plasmid DNA in a short time is a relatively simple, efficient and safe method for in vivo transfection of liver cells. Though used for quite some time, the mechanism of gene transfection has not yet been elucidated. Methods: A luciferase encoding plasmid was injected using the hydrodynamics based procedure into normal and thioacetamide-induced fibrotic Sprague Dawley rats. Scanning and transmission electron microscopy images were taken. The consequence of a dual injection of Ringer solution and luciferase pDNA was followed. Halofuginone, an anti collagen type I inhibitor was used to reduce ECM load in fibrotic rats prior to the hydrodynamic injection. Results: Large endothelial gaps formed as soon as 10′ following hydrodynamic injection; these gradually returned to normal 10 d post injection. Hydrodynamic administration of Ringer 10 or 30 m prior to moderate injection of plasmid did not result in efficient transfection suggesting that endothelial gaps by themselves are not sufficient for gene expression. Gene transfection following hydrodynamic injection in thioacetamide induced fibrotic rats was diminished coinciding with the level of fibrosis. Halofuginone, a specific collagen type I inhibitor, alleviated this effect. Conclusion: The hydrodynamic pressure formed following HBT results in the formation of large endothelial gaps. These gaps, though important in the transfer of DNA molecules from the blood to the space of Disse are not enough to provide the appropriate conditions for hepatocyte transfection. Hydrodynamics based injection is applicable in fibrotic rats provided that ECM load is reduced. © 2006 The WJG Press. All rights reserved.