Mice were subjected to tail vein hydrodynamic injection of the siRNA/in vivo-jetPEI-Gal system, that comprised in vivo-jetPEI-Gal transfection reagent (PolyPlus Transfection, IIIkirch, France) and siRNA. The siRNA/JetPEIGal complex: 5 µL siRNA (40 µg) in 45 µL water and mixed with 50 µL 10% glucose (solution A) and 2 µL in vivo-jetPEI-Gal diluted in 48 µL water and mixed with 50 µL 10% glucose (solution B) were mixed, left for 15 min at room temperature and vortexed. After transfection, serum and liver biopsy specimens were harvested at the indicated time points for further analyses.

The chemokine monokine induced by interferon-gamma (Mig) is involved in the recruitment of inflammatory cells and liver injury during hepatitis B virus (HBV) infection. HBV protein X contributes to Mig expression in vitro by activation of nuclear factor (NF)-kappaB; however, the molecular mechanisms by which HBV induces Mig expression in vivo are unknown. In this paper, we established a mouse model for HBV study by tail vein injection of HBV genome-containing adenovirus vectors. Host immune response to the secreted hepatitis B surface antigen and e antigen was detected and serum alanine aminotransferase (ALT) was elevated at different time points. We also demonstrated that peripheral and intrahepatic Mig expression was increased after Ad-HBV infection. This was followed by inflammatory cell migration and formation of inflammatory foci in the liver. In addition, NF-kappaB p65 subunit translocated from the cytoplasm to the nucleus, and phosphoinositide 3-kinase/Akt, extracellular signal-regulated kinase (ERK) and c-Jun N-terminal kinase (JNK) were to some extent phosphorylated after HBV injection. Following tail vein injection of Mig siRNA/in vivo-jetPEI-Gal complex, Mig expression was partially suppressed, inflammatory cell migration was inhibited, serum level of ALT were reduced. In conclusion, through NF-kappaB activation, HBV induced Mig expression in vivo, which recruited peripheral inflammatory cells to the liver and resulted in liver damage. Phosphorylation of phosphoinositide 3-kinase/Akt, ERK and JNK but not p38 might involved in the molecular mechanisms underlying HBV induced Mig expression in vivo.