Abstract:

Objective To observe the changes of CD107a production by T cells and their subsets in peripheral blood at different stages of patients with chronic HBV infection and during the antiviral treatment with Peg⁃interferon，and to explore the rule of the change of T cell cytotoxicity during different stages of chronic HBV infection and antiviral therapy with interferon. Methods Patients with chronic HBV infection were enrolled into the study，with a cross⁃section cohort（n = 300，treatment⁃naive）and a longitudinal cohort（n = 36，HBeAg⁃positive， ALT > 2 ULN，receiving Peg⁃interferon therapy after enrollment）. Peripheral blood before and after antiviral treat⁃ ment was collected from the two cohorts of patients. The production of CD107a by T cells was detected by flow cytometry. Results （1）The levels of CD107a produced by CD3+，CD4+ and CD8+ T cells in patients of immune⁃ active stage（IA）were significantly higher than that in patients of immune⁃tolerant stage（IT）and inactive carrier stage（IC）.（2）The levels of CD107a production by CD3+，CD4+ and CD8+ T cells was found positively correlated with liver inflammatory indexes（ALT，AST and total bilirubin）.（3）The levels of CD107a production by CD3 +， CD4+ and CD8+ T cells were also showed a significant positive correlation with liver fibrosis（liver stiffness measure⁃ ment，APRI and FIB⁃4 score）.（4）The levels of CD107a production by CD3+，CD4+ and CD8+ T cells were signifi⁃ cantly higher in HBeAg（+）patients than those in HBeAg（-）patients，and those in patients with HBV DNA > 106 IU/mL was significantly higher than those in patients with HBV DNA < 106 IU/mL.（5）The levels of CD107a production by CD3+，CD4+ and CD8+ T cells were significantly increased after 48 weeks of treatment with PEG⁃ interferon compared with those before treatment. Conclusion The cytotoxic effect of T cells to secret CD107a is not only positively correlated with liver inflammation and fibrosis，but also with HBV replication level. The cytotoxic effect of T cells is obvious higher in immune active stage of chronic HBV infection，and moreover，that capacity of T cells could be significantly enhanced after antiviral treatment with Peg⁃interferon.

Key words:

T cells, CD107a, Peg?interferon, chronic hepatitis B