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.