Abstract: | The number of lymphocytes expressing CD3, CD4, CD8, CD16, CD25, and CD19 antigens was studied in patients with chronic hepatitis C before and after 12-week therapy with interferon-alpha (IFN-alpha). The percentage of cells expressing CD4+, CD16+, and CD25+ antigens decreased significantly in untreated patients, while the percentage of CD8+ and CD19+ lymphocytes was increased (p < 0.05) vs. the control. After 3-month therapy with IFN-alpha the counts of CD4+ and CD25+ increased significantly in patients with chronic hepatitis C (p < 0.05 and p < 0.01, respectively) in comparison with the initial values. The treatment led to a significant (p < 0.05) decrease in the number of CD8+ cells in the blood. The number of cells expressing CD19+ decreased, but remained high in comparison with the control. These results indicate that cellular immune response is inadequate in patients with chronic hepatitis C. Time course of subpopulation composition of T lymphocytes during effective treatment with IFN-alpha indicates an important role of T-cellular component of immunity in the antiviral defense mechanisms in chronic HCV infection. |