Intracellular localization of NS3 and C proteins in chronic hepatitis C

Aims and methods: The cellular localization of hepatitis C virus (HCV) proteins in chronic hepatitis C remains a debatable issue. Aim of the studies included cellular and subcellular localization of two HCV proteins, NS3 and C protein, in liver biopsies from 20 children with chronic hepatitis C employing commercially available monoclonal antibodies and a semiquantitative technique of the proteins expression. In the studies advantage was taken of (Strept)avidin-biotin peroxidase complex and ImmunoMax technique. Results: The cytoplasmic localization of both proteins dominated over nuclear localization. The total amount of NS3 protein exceeded that of C protein. At the ultrastructural level, we observed both proteins in endoplasmic reticulum membranes and mitochondria, but small amount of both proteins was seen also in cell nuclei. The amount of either protein did not correlate with liver histology in our patients. No correlation could be disclosed between content of both proteins and HCV RNA levels in serum. Content of NS3 demonstrated negative correlation with activity of alanine transaminase. Conclusion: In conclusion, the new aspect in present studies involved localization of C and NS3 proteins at the levels of light and electron microscopy in children. For the first time also intramitochondrial localization of NS3 protein was demonstrated.