An epitope chimeric antigen for the hepatitis C virus serological screening test.

The epitope chimeric antigen, CepCM, composed of the 9 selected major epitope regions (two in NS3, two each in the NS4 of two genotypes, two each in the core of two genotype, and one in the core in hepatitis C virus (HCV) polypeptide), was expressed as a fusion protein of the trpE peptide in E. coli. An ELISA test using this antigen produced the same judgements with most of the panel sera as a second generation HCV screening kit. Though discrepancies were found in twelve samples (5% of the samples), further analysis revealed that eleven samples were indeterminate sera as judged by an immunoblot test. The reactivity found in several seroconversion series sera suggested that CepCM has superior reactivity to HCV infected sera than some second generation kits. These data indicated that an epitope chimeric antigen with a man-made sequence will be a excellent tool for a diagnostic test kit.