Abstract: Objective: To package five recombinant retroviral vectors containing the enhanced green fluorescent protein (EGFP) gene and screen for the best hepatocytes-targeting retroviral vector. Methods: Four additional expression plasmids were constructed based on the previously constructed fusion expression plasmid. Following a simultaneous transfection of five plasmids and plasmid pL-EGFP into NIH3T3 packaging cells respectively, which can stably express gag-pol protein, recombinant retroviral vectors were achieved 48h post-transfection. The virus supernatant was collected and used to infect HepG2215 and 293T cells. The total RNA of 48 h post-infected cells was extracted, and the tropism of the recombinant vectors were compared by real-time PCR. Results: Four additional expression plasmids were successfully constructed by enzyme digest identification. The viruses titer was about 10⁵ cfu/ml, and the retrovirus stocks packaging with the plasmid pcDNA3.1(-)-env^m-preS1-S2 had a better hepatocellular tropism. Conclusion: The recombinant retroviral vector which has a better hepatocellular tropism would provide great help for packaging the virus vector carrying the HDV ribozyme and studying the inhibition on HBV replication and expression induced by the HDV ribozyme.

Key words: Hepatocytes, Retroviridae, Retroviridae proteins, DNA mutational analysis, Polymerase chain reaction