Preliminary Study On The Infection Of HepG2 And L02 Cells By HBV Wild Strain And Variant

Objective: HepG2 and L02 cells were infected with serum-derived HBV variant and wild strain,in order to evaluate the ability of two kinds of cells infected with HBV, and to investigate the difference of replication between them.Methods:Collect the serum of patients infected with HBV including Adefovir resistance,lamivudine resistance and wild strains,respectively. After HepG2 and L02 cells were cultured by 2% DMSO for 4 days, these serum were added into cells to co- incubated with DMSO for 12h,respectively. Collect the supernatant of infected cell at 0, 1, 2, 4, 6, 8, 10 days. The levels of HBsAg were detected by Time-Resolved Fluorescence immunoassay, and HBV DNA concentrations were detected by Real-time quantitative PCR assay. After infection 0, 24, 48, 96 hour, the intracellular localization of HBcAg were measured by Immunofluorescence assay.Results:1.The levels of HBsAg were increasing in HepG2 and L02 cell supernatant , reaching a peak at 2 days after infection, and then declining with the delay of curltured time. 2. The HBV-DNA concentrations were also increasing in HepG2 and L02 cell supernatant. After infection for 4 days, HBV-DNA levels reached a peak and then gradually declined.3. After infection for 24h, HBcAg was strong signal expressed firstly in the cytoplasm, homogeneous distribution and absent in the nucleus; After infection for 48h, HBcAg expression was appeared in the nucleus and decreased in the cytoplasm; after 96h , the expression of HBcAg was reduced in the nucleus and the cytoplasm.4. After HepG2 cells were incubated with DMSO and serum from Adefovir resistance, lamivudine resistance and wild strains of paitents with HBV infection , there was statistical significance about the levels of HBsAg in the supernatant, also there was abvous difference about HBV DNA concentrations ,respectively (p<0.05). However, there was no significant difference between ADV mutant and LAM mutant (p>0.05). Pairwise comparison, there were statistical significance(p<0.05).5. After L02 cells were incubated for serum from Adefovir resistance,lamivudine resistance and wild strains of HBV with DMSO, there was statistical significance about the amount of HBsAg in the supernatant, (p<0.05). In contrast, there was abvous difference between ADV mutant and HBV wild type (p<0.05). Pairwise comparison, there was no difference(p>0.05).Conclusion:Serum-derived HBV could infect HepG2 and L02 cells, the replication of HBV variant is weaker than that of wild strain.