Construction Of Cellular Model For Regulating Expression Of HBV Gene In Lentivirus System

Hepatitis B, caused by Hepatitis B virus (HBV), is one of worldwide epidemic diseases endangering human health. Among the affected individuals, approximately350million are chronic carriers of HBV. HBV infection has revealed clinical courses from asymptomatic infection to chronic hepatitis, liver cirrhosis or hepatocellular carcinoma (HCC). Heretofore HepG2cells, HCC tissue, transgenic mouse and others were usually used as models for studying HBV. In all these models, HBV DNA had stably been integrated into the genome, which was a static process compatible with the host cell and couldn’t reflect the dynamic changes after infected by virus, as the model of mechanism research between the viral antigen and host. Here the tetracycline regulation lentiviral system was utilized to achieve the regulated HBV gene expression, contributing to understanding the overall changes of the different stages in the cells.The tetracycline regulating expression plasmid containing seven HBV genes (X, P, C, preC-C, S, preS2-S, preSl-S2-S) were constructed. The plasmids were transfected into the lentiviral packaging cell line HEK293T cells, and the virus particles containing the regulating gene pLVX-Tet-On and the expression gene pLVX-GOI were gained. The virus titer was about108LPs/ml. HepG2and L02cell lines were infected by two types of viruses and selected with G418and puromycin antibiotics. Hence the tably HBV infected cell models were constructed. Finally it was demonstrated that the gene integrated into cells, and HepG2-X/LS RNA expression is induced in HepG2-X/LS cells. Also X protein can be induced expression in HepG2-X cells. The HBV gene inserting into the cell model of inducing expression provides an ideal experimental cell model for studying the role of HBV in the HBV infection and the host immune tolerance.