Background/aims: Persistent hepatitis B virus (HBV) infection is associated with particular deficiencies in the host immune system. To gain insight into the role of lymphocyte subsets involved in viral clearance and hepatic injury.
Methodology: The immunophenotype of peripheral blood and biopsied liver tissues in hepatitis B patients were examined.
Results: Among lymphocyte subsets analyzed, CD45RA+CD62L+ subsets were significantly lower in HBV-infected livers than in healthy controls. Intrahepatic naive lymphocytes was negatively correlated with serum viral load (r =-0.47, p<0.05) and liver injury measured by serum alanine aminotransferase (ALT) (r=-0.36, p<0.05). Serum HBV DNA was also negatively associated with intrahepatic CD8+CD95+ (r=-0.49, p<0.01), circulating CD4+HLA-DR+ (r=-0.43, p<0.05) and circulating CD3+CD(16+56)+ (r =-0.35, p<0.05). CD3+CD8+ subsets were positively correlated with serum ALT and HBV DNA (r=0.56, 0.74, p<0.01), respectively.
Conclusions: These data suggest a key role for the exhaustion of intrahepatic naive lymphocyte reservoir in the development of a weak antiviral immune response and the inability to control viral replication in chronic hepatitis B patients. While cellular immunity is critical to clear the viral load, over-activated cytotoxic lymphocytes may also be involved in hepatic injury.