Pegylated Interferon Alpha-2b Up-Regulates Specific Cd8+T Cells In Patients With Chronic Hepatitis B

AIM: To investigate the effect of pegylated interferon (IFN) alpha-2b on specific CD8+ T lymphocytes in patients with chronic hepatitis B (CHB).METHODS: Twenty-one patients with CHB were treated with pegylated IFN alpha-2b. Periphery blood mononuclear cells were isolated from fresh heparinized blood by Ficoll-Hypaque density gradient centrifugation (density: 1.077 g/L, Pharmingen) at weeks 0, 4, 8, 12, and 24, respectively. Frequency of circulating hepatitis B virus (HBV) epitope-specific CD8 T cells was detected by flow cytometry. Cytokines were detected by cytometric bead assay.RESULTS: The frequency of circulating HBV core or env-specific CD8 T cells was higher (P < 0.05), the number of HBV core specific CD8 T cells was greater at week 24 (P < 0.05), the level of Th1-type cytokines [interleukin (IL)-12, tumor necrosis factor-alpha, and IFN-gamma] was higher, while that of Th2-type cytokines (IL-4, IL-6, and IL-10) was lower in responders than in non-responders (P < 0.05) after pegylated IFN alpha-2b treatment. The IL-6 level was correlated with HBV DNA (r = 0.597, P = 0.04), while the inducible protein-10 (IP-10) level was correlated with serum alanine aminotransferase (ALT) (r = 0.545, P = 0.005). The IP-10 level at week 8 after pegylated IFN alpha-2b treatment could predict the normalization of ALT in CHB patients (positive predict value = 56%, negative predict value = 92%).CONCLUSION: Pegylated IFN alpha-2b can enhance the immune response of CHB patients by increasing the frequency of HBV specific CD8+ T cells and regulating the Th1/Th2 cytokines. (C) 2010 Baishideng. All rights reserved.