Efficiency of adenovirus-mediated gene transfer into hepatocytes by liver asanguineous perfusion method

Efficient targeted gene delivery is essential for successful gene therapy. In this study, we examined the liver asanguineous perfusion method (LAP) fo r adenovirus-mediated gene transfer to the liver from the standpoints of ef ficiency, tissue-specificity and safety. The adenoviral vector containing t he E. coli LacZ gene driven by the CAG promoter was delivered to the livers of rats by LAP. This method involves selective in situ perfusion, with the liver isolated by clamping of the afferent and efferent blood vessels to p revent adenoviral vector dissemination and genetic modification of nonhepat ic organs. We demonstrated that gene transfer to the liver by LAP was not u niform, but more efficient than by intravenous (IV) or intraportal (IP) inf usion, and caused no obvious liver damage or high mortality. As determined by specific histochemical staining and polymerase chain reaction, the amoun t of vector DNA transferred to the nonhepatic organs by LAP was significant ly less than that transferred by the other two methods. Our data suggest th at LAP is clearly superior to TV or IP infusion in terms of efficiency, spe cificity and safety of gene delivery to the liver. Further reduction in sur gical risk is needed for the clinical application of gene therapy.