In situ perfusion of the liver enhances the efficiency of retrovirus-mediated gene transfer to hepatocytes

To increase the efficiency of retrovirus-mediated gene transfer targeting a n individual's liver in vivo, the liver was perfused in situ with the retro virus vector during hepatic cold ischemia. Four weeks prior to gene transfe r, the spleen was transpositioned to the left subcutaneous position to deve lop a portosplenic shunt, which was performed in order to prevent intestina l congestion during hepatic ischemia. Traditional retrovirus vectors (1 x 1 0(5) CFU/ml) which encode genes for the Escherichia coli beta-galactosidase (LacZ) were used in this study. Twenty-four hours after partial hepatectom y (70%), the remnant liver was surgically isolated, perfused with 1 mi of v ector solution through the portal vein, and kept in contact with the vector for 30 min under cold ischemia (group 1). Hepatic ischemia could thus be p erformed without any intestinal congestion, due to the preestablished porto systemic shunt. In group 2, the liver was perfused with 1 mi of vector solu tion through the portal vein without in situ perfusion of the liver. Animal s were sacrificed 1, 3, 7 and 28 days after gene transfer. In X-gal stainin g, the transferred LacZ was detected positive in 10-15% of the hepatocytes only in group 7, 3 days after gene transfer. Graft histology and a liver fu nction test showed no difference between both groups 24 h after gene transf er. In conclusion, in situ perfusion of the liver greatly enhanced the effi cacy of retrovirus-mediated gene transfer, targeting an individual's liver in vivo. Copyright (C) 2000 S. Karger AG, Basel.