OBJECTIVETo investigate the optimal approach of lentiviral vector transfection for effective delivery of exogenous gene into the liver.

METHODSThe lentiviral vector was delivered via the ileocolic vein of the ileocecus (portal vein group) or via the caudal vein of SD rats. The effect gene transfection into the liver was assessed by observing the expression of green fluorescence protein expression carried by the lentiviral vector, silencing of LXRα mRNA expression mediated by RNA interference, and liver transaminase changes. The efficiency and safety of the two approaches of transfection were evaluated.

RESULTSAll the rats receiving lentiviral transfection survived. In the portal vein group, abundant green fluorescence was detected in the liver at 96 h following the transfection and lasted till 14 days, whereas only weak fluorescence was observed in the caudal vein group. The results of RT-PCR demonstrated a significant higher rate of LXRα knock-down in portal vein group than in caudal vein group (0.135∓0.002 vs 0.713∓0.036, P<0.05). No significant difference in ALT levels found between the two groups.

CONCLUSIONSInfusion via the potal vein is effective for gene transfection into the liver, and puncture from the ileocolic vein of ileocecus can guarantee the survival of rats and improve the transfection efficiency without causing liver injury.

Animals ; Gene Expression ; Genetic Vectors ; Lentivirus ; genetics ; Liver ; metabolism ; Male ; RNA Interference ; RNA, Messenger ; genetics ; Rats ; Rats, Sprague-Dawley ; Transfection

OBJECTIVETo investigate whether RNA interference (RNAi) of LXRα gene in donor rats with fatty liver improves liver graft function after transplantation.

METHODSFifty donor SD rats were fed a high-fat diet and 56% alcohol to induce macrovesicular steatosis exceeding 60% in the liver. The donor rats were injected via the portal veins with 7 × 10⁷ TU LXRα-RNAi-LV mixture (n=25) or negative control-LV (NC-LV) vector (n=25) 72 h before orthotopic liver transplantation. At 2, 24, and 72 h after the transplantation, the recipient rats were sacrificed to examine liver transaminases, liver graft histology, immunostaining (TUNEL), and protein and mRNA levels of LXRα.

RESULTSLentivirus-LXRα RNAi inhibited LXRα gene expression at both the mRNA and protein levels in the liver graft and reduced the expressions of SREBP-1c and CD36 as compared with the controls, resulting also in reduced fatty acid accumulation in the hepatocytes. The recipient rats receiving RNAi-treated grafts showed more obvious reduction in serum ALT, AST, IL-1β and TNF-α levels, and exhibited milder hepatic pathologies than the control rats after the transplantation. TUNEL assay demonstrated a significant reduction in cell apoptosis in LXRα-RNAi-LV-treated liver grafts, and the rats receiving treated liver grafts had a prolonged mean overall survival time.

CONCLUSIONLXRα-RNAi-LV treatment of the donor rats with fatty liver can significantly down-regulate LXRα gene expression in the liver graft and improve the graft function and recipient rat survival after liver transplantation.

Animals ; Fatty Liver ; genetics ; surgery ; Gene Expression Regulation ; Hepatocytes ; cytology ; Lentivirus ; Liver ; physiology ; Liver Transplantation ; Liver X Receptors ; Orphan Nuclear Receptors ; genetics ; RNA Interference ; RNA, Messenger ; Rats ; Rats, Sprague-Dawley