Efficient hepatitis C antigen immunohistological staining in sections of normal, cirrhotic and tumoral liver using a new monoclonal antibody directed against serum-derived HCV E2 glycoproteins.

Detection and localization of Hepatitis C Virus (HCV) in liver tissue is useful for diagnostic purposes as well as to elucidate the mechanisms by which the virus participates in hepatocarcinogenesis. However, so far, a sensitive method for HCV detection at the cellular level is lacking. We describe here the application of a novel antibody, D4.12.9, developed against serum-derived HCV RNA-positive particles, for the detection of E2 proteins by immunohistochemistry in fixed, archived specimens including liver biopsies of HCV-infected patients and surgical specimens of hepatocellular carcinoma. We demonstrate that D4.12.9 is a powerful tool for sensitive and specific detection of HCV, independently of viral genotype. This approach has applications to diagnosis as well as exploratory pathological studies.