Performance of an enzyme-linked immunosorbent assay system for antibodies to hepatitis C virus with two new antigens (c11/c7).

We developed an enzyme-linked immunosorbent assay (ELISA) system for antibodies to the hepatitis C virus (HCV), using two new recombinant antigens (c11 and c7) derived from the HCV genome. The performance of this ELISA system (Imucheck HCV Ab) was examined. The CV values for both intra-assay precision and reproducibility of identifying HCV antibody in the panel sera ranged from 3.5% to 6.4%. The blood elements in serum and anticoagulants did not interfere in this ELISA system. The specificity of Imucheck HCV Ab to samples from patients with non-A, non-B (NANB)-type chronic hepatitis, liver cirrhosis, and hepatocellular carcinoma was 93.7%, 93.5%, and 81.4%, respectively. These results are more sensitive than those obtained by the first-generation anti-HCV ELISA system. In the samples from patients with NANB-type acute hepatitis, Imucheck HCV Ab enabled detection of HCV antibodies at an early stage. This system increased the sensitivity for blood donor screening and for monitoring patients with acute hepatitis.