[Specific antibody assay for genotyping of hepatitis C virus]

Based on their nucleotide sequences and the deduced amino acid sequences, most hepatitis C virus (HCV) isolates have been classified into two genotypes, type 1 (subtype 1a and 1b) and type 2 (subtype 2a and 2b). Using part of the putative NS4 protein region (amino acids No. 1676-1760) as antigens, an enzyme-linked immunosorbent assay (ELISA) was developed. The results of genotyping of HCVs in chronic hepatitis patients by this ELISA system were almost completely consistent with those by PCR. The genotype 1 HCV infected patients showed a poor response to interferon (IFN) therapy. In contrast, genotype 2 HCV infected patients showed good response. The results suggest that genotype 1 and 2 HCVs possess different biological properties.