COMPARISON BETWEEN CYTOMEGALOVIRUS PROMOTER AND ELONGATION FACTOR-1-ALPHA PROMOTER-DRIVEN CONSTRUCTS IN THE ESTABLISHMENT OF CELL-LINES EXPRESSING HEPATITIS-C VIRUS CORE PROTEIN

The establishment of stable cell lines expressing the hepatitis C viru s (HCV) core protein may be important for studies of HCV pathogenesis. Human and mouse cell lines were generated expressing the HCV core pro tein using expression vectors driven by either the cytomegalovirus (CM V) or elongation factor-1 alpha (EF-1 alpha) promoters. Following tran sient transfection, HCV core protein was expressed in all cell lines. However, stable human hepatocellular carcinoma (HCC) and murine myelom a cell lines expressing the HCV core protein were only established usi ng constructs driven by the EF-1 alpha promoter. In contrast, stable e xpression of the hepatitis B virus (HBV) middle envelope protein (MHBs ) was obtained successfully in these cell lines using an expression ve ctor driven by the CMV promoter. Inhibitory activity of the first 69 a mino acids of the HCV core protein on the CMV promoter was found by us ing chimeric MHBs/HCV core protein constructs. Growth of cloned cell l ines expressing the HCV core protein was slower than that of nonexpres sing cell lines. However, morphological changes and cell death were no t observed in the stable cell lines expressing HCV core protein. These results indicate that the HCV core protein was not directly cytotoxic to HCC and myeloma cell lines but that specific promoter elements are required to establish stable expression of the nucleocapsid structura l protein. Copyright (C) 1997 Elsevier Science B.V.