T-lymphocyte subsets in peripheral blood and liver tissue of patients with chronic hepatitis B and C.

AIM To evaluate the immune response in peripheral blood and liver tissue, through the measurement of T-cell subsets, in patients with chronic hepatitis B (CHB) and C (CHC). PATIENTS AND METHODS Thirty-four patients with CHB (21 with active HBV infection and 13 inactive HBV carriers) and 20 patients with CHC were included in the study. We also evaluated 21 biopsies from patients with active CHB infection and 20 patients with CHC. We measured CD3, CD4, CD8 and CD4/CD8 ratio in peripheral blood and liver tissue. RESULTS We found no differences in the numbers of all T-lymphocyte subpopulations between patients with active HBV infection and inactive carriers. We found a significant increase in the absolute numbers of CD3(+), CD4(+) and CD8(+) T-lymphocytes in CHC compared to CHB patients (p=0.005, p=0.034 and p<0.0001 respectively). There was a significant increase in the number of CD3(+) and CD8(+) T-lymphocytes in the area of portal tracts (p=0.012 and p=0.009 respectively) and lobules (p=0.011 and p=0.01 respectively) in patients with CHC compared to those with CHB. In both groups there was a direct correlation between CD3(+) cells in portal tracts and HAI score (r=0.783, p=0.008), while we noted a correlation between CD8(+) cells in portal tracts and HAI score only in patients with CHC. Interface hepatitis correlated to CD3(+) cells in lobules of patients with CHC and CHB but a direct relationship between CD8(+) cells and HAI score was found only in those with CHC. CONCLUSION Insufficient cellular immune response is critical for the ineffective virus clearance and liver damage in chronic hepatitis B, while in chronic hepatitis C, immune response, as represented by CD8(+) T-cells, is present in the peripheral blood and the liver. However, there is an immunological escape of HCV, which seems to survive in the presence of an adequate immune response. The significant correlation between portal and periportal CD8(+) T-lymphocyte expression and interface hepatitis may be considered evidence of the occurrence of cytotoxic immune-mediated toxicity.