Objective: To explore the role played by HBV antigen specific cytotoxic lymphocytes (CTLs) in severe hepatitis B patients.
Methods: Three kinds of HBV specific CD8+ T cells responding to HBV core 18-27, polymerase 575-583 and envelope 335-343 specific CD8+ T cells were searched with major histocompatibility complex (MHC)-peptide tetramer flow cytometry in the patients we studied. The cytokines produced by these specific CTLs such as IFNgamma, TNFalpha, IL-4, IL-10 were detected using ELISPOT assays. Their ability to lyse target cells was analyzed using a CytoTox96 Non-Radioactive Cytotoxicity Assay kit (Promega).
Results: The number of HBV core 18-27 specific CD8+ T cells was significantly higher in the peripheral blood of acute severe hepatitis B group patients than that in chronic severe hepatitis group (P less than 0.05), but lower than that in the acute hepatitis B patients. The IFNgamma and TNFalpha levels of acute severe hepatitis B patients were both significantly higher than those in the chronic severe hepatitis group (P less than 0.05). The ability to lyse target cells of HBV core 18-27 CTLs was also significantly higher in the acute severe hepatitis B group than that in the chronic severe hepatitis B group (P less than 0.05).
Conclusion: The response to antigen stimulation was much higher in acute severe hepatitis B than in chronic severe hepatitis B patients. The specific CTLs persisted among the peripheral blood mononuclear cells in acute severe hepatitis B, which may be related to the viral clearance.