EXPRESSION OF HCV CORE PROTEIN IN ESCHERICHIA-COLI AND THE ESTABLISHMENT OF ELISA SYSTEM

Protein encoded by the cDNA of the core region of hepatitis C virus (H CV) was expressed as a fusion protein with beta-galactosidase (beta-ga l) in Escherichia coli, and an ELISA system was established using this fusion protein for diagnosis of HCV infection, Using this ELISA syste m, a comparative study with anti-C100 antibody ELISA was undertaken in 150 cases of NANB acute hepatitis, chronic hepatitis, liver cirrhosis and hepatocellular carcinoma. Anti-C100 antibody positivity rates wit h these diseases were 62.5, 71.1, 75.0 and 75.0%, respectively, while anti-JCC antibody positivity rates were as high as 75.0, 85.6, 92.5 an d 91.7%, respectively. On average, the positivity rate of anti-C100 an tibody was 72.0%, while that of anti-JCC antibody was 87.3%. In the lo ng-term analyses of two clinical cases regarding the antibody response s to these different proteins, anti-JCC antibody had a tendency to be detected earlier than anti-C100 antibody, although the time of detecti on in relation to ALT peaks was dependent on the case.