Phenotypic and functional characterization of intrahepatic T lymphocytes during chronic hepatitis C

The pathogenesis of liver cell injury during chronic hepatitis C (CHC) is poorly understood. The cellular immune response is thought to play a key role in both inhibition of viral replication and liver pathology. However, little is currently known about which lymphocyte populations and which immune effectors contribute to or control liver damage. We investigated a panel of 15 phenotypic and functional markers of intrahepatic T-lymphocyte subsets irrespective of their antigen specificity in 48 hepatitis C virus (HCV)-infected patients and 8 healthy control subjects. Lymphocyte characteristics were evaluated from liver biopsy specimens both at gene expression level by real-time quantitative reverse-transcription polymerase chain reaction (RT-PCR) and by immunochemistry, in relation with the degree of liver injury and with intrahepatic HCV-RNA levels. As compared with controls, we found major changes in T-lymphocyte subsets in HCV-infected patients, with a significant decrease of T-cel...