Detection of Hepatitis C Virus Core and NS3 Protein in Paraffin-Fixed Liver Tissue by Using a Modified Immunodetection System
M Ficarra, H LeBeau, S Florman, F Regenstein, S Dash, S Haque. Tulane University Health Sciences Center, New Orleans, LA
Background: Hepatitis C virus (HCV) is a common blood borne hepatotrophic virus that causes chronic liver disease, cirrhosis and hepatocellular carcinoma. Diagnosis of chronic HCV infection and response to antiviral therapy in the clinical practice is currently established mostly by clinical and morphologic criteria and by detection of virus by a highly sensitive RT-PCR method. However, a reliable method to detect viral antigen in the liver tissue should be rapid, reliable, cost-effective, and a routine step in patient medical care. Aim: To develop an immunohistochemical method that can reliably detect the expression of HCV antigen in the formalin-fixed liver tissue of chronically infected humans. Design: In this study, HCV positive and HCV negative paraffin-fixed liver explants specimens were randomly selected from the files of Tulane University Health Sciences Center. Formalin fixed liver tissue sections were stained for HCV core and NS3 protein by using two different mouse monoclonal antibodies. Immunostaining was performed using a protocol that includes a Biotin-Free Universal HRP-Polymer detection method. Results: The polymer detection system is sensitive enough to detect the expression of HCV core and NS3 protein in the liver tissue. We were able to localize cytoplasmic expression of core and NS3 protein in all the HCV positive livers but not in the controls. In each case approximately 20- 40 % of hepatocytes showed positive staining to both antibodies. The immunoreactivity was also seen within some Kupffer cells and macrophages. Conclusions: We developed a method that can reliably detect HCV protein in paraffin-embedded, formalin-fixed liver tissue from chronically infected patients. This method can be utilized for routine histological evaluation of HCV in pathology laboratories.
Category: Liver & Pancreas
Monday, March 9, 2009 1:30 PM
Platform Session: Section E, Monday Afternoon