Immunohistochemical detection of HCV proteins in liver tissue.

Detection and localization of HCV in liver tissue are vital for diagnostic purposes and clinical management of HCV-infected patients, as well as for the elucidation of viropathological mechanisms. The fragility of HCV RNA and the low levels of viral expression in infected tissues are a constant limitation in molecular assays for HCV characterization. HCV antigen detection, by immunochemistry, in liver biopsies is an attractive option for precise localization and quantification of viral proteins with direct access to histological patterns. We describe here a study using a novel immunohistochemical method effective on fixed, archived specimens, including liver biopsies and surgical resection samples. The initial protocol uses a biotin-detection system but can also be used in a polymer-detection system. This protocol offers easy, precise, and strong staining resolution with distinct patterns consistent with the liver pathology, irrespective of the viral HCV genotype examined. This approach provides applications for diagnosis as well as for exploratory pathological studies.

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.