Hepatitis C Virus NS2 Protein Suppresses the Activities of NF-κB in Huh-7 Cell Line*

Recombinant plasmid pCNS2 was constructed by inserting Hepatitis C Virus full-length NS2 gene between Xho I and Hind III sites of an eukaryotic expression vector pCDNA3.1(-). The recombin- ant plasmid pCNS2 was transfected to Huh-7 cells with LipoVecTM and HCV NS2 mRNA and protein produced in transient expression system was detected at the transcriptional and translational levels，respe- ctively. This indicated that pCNS2 could be expressed successfully in Huh-7 cells. Cotransfected pCNS2 of different doses to Huh-7 cells with reporter plasmid pNF-κB-Luc，the activity of luciferase controlled by NF-κB promoter/enhancer elements was detected by luciferase assay kit 48h after transfection. The results showed that the expression of luciferase in Huh-7 cells transfected by the pCNS2 decreased about two to four folds compared to control plasmid. It is suggested that the HCV NS2 protein distinctly suppressed the activities of NF-κB in a dose-dependent manner in Huh-7 cells and this will enable to investigate on the role of NS2 in the pathogenesis of chronic HCV infection.