Abstract: The present invention relates to a novel process for preparing hepatitis C virus (HCV) envelope glycoproteins employing Chinese Hamster Ovary (CHO) cells transformed with recombinant expression vectors containing the hepatitis C virus genome. The present invention provides CHO cells cotransfected with DHFR (dihydrofolate reductase) minigene pDCHIP and recombinant expression vectors containing cDNAs of HCV E1 and E2/NS1 ligated with tissue plasminogen activator signal sequence. HCV E1 and E2/NS1 envelope glycoproteins are produced in a massive manner from the transformed CHO cells adapted in methotrexate. The HCV envelope glycoproteins produced by the present invention can be applied to the development of a diagnostic reagent and a potential preventive HCV vaccine.

Abstract: The present invention relates to a novel cDNA of direct-acting fibrinolytic serine protease ("Salmonase") which is prepared from a Korean viper, Salmosa(Agkistrodon halys brevicaudus), and a direct-acting fibrinolytic serine protease deduced therefrom. The cDNA of direct-acting fibrinolytic serine protease contains 699 nucleotides coding for 233 amino acids, and the Salmonase translated therefrom consists of two subunits of 77 and 156 amino acids, respectively. Salmonase cDNA of the invention may be expressed in the proper systems established in the recombinant E. coli, yeast, baculovirus/insect cells and other animal cells, and the recombinant Salmonase prepared therefrom can be practically applied as an active ingredient of thrombolytic and hemostatic agents.

Abstract: The present invention relates to a novel use of a biologically active protein, p53 as an inhibitor of hepatitis B virus(HBV) replication. The inhibitory role of p53 on HBV replication was assessed by the reduced levels of three different markers, i.e., HBsAg and HBc/eAg secreted into the medium, HBV DNA, and RNAs. Based on the above results, it was concluded that wild-type p53 specifically represses the activity of pregenomic/core promoter of HBV and inhibits the replication of HBV by down-regulation of the pregenomic/core promoter. Therefore, the present invention provides a novel use of protein p53 as a HBV replication inhibitor which can be developed into an agent for the treatment of acute/chronic hapatitis and prevention of liver cirrhosis and hepatocellular carcinoma(HCC) caused by HBV.