Localization of hepatitis C viral RNA and capsid protein in human liver.

In the livers of patients whose sera contained antibodies to C100-3 antigen (anti-HCV) and hepatitis C virus (HCV) RNA, the presence of HCV RNA and HCV capsid protein (CP) antigen was demonstrated by in situ hybridization and immunohistochemistry, respectively. It was found that occasional hepatocytes in four of ten livers from patients whose sera were positive for both anti-HCV and HCV RNA hybridized with antisense as well as sense oligonucleotide DNA probes, whereas the probes did not hybridize with livers from patients whose sera were negative for anti-HCV and HCV RNA. Monoclonal antibody against a synthetic oligopeptide with amino acid sequence of HCV CP reacted with occasional hepatocytes in six of 14 livers from patients whose sera contained these HCV markers, but not with livers from patients whose sera were negative for both of them. These results suggest that HCV proliferates within hepatocytes since both antisense and sense probes hybridized with cytoplasm of the hepatocytes and that the virus matures in the cytoplasm as the capsid proteins were also found in the hepatocytes.