Study on antigen-specific T cells in chronic hepatitis B patients accepting antiviral therapy
Objective To explore the responses of antigen-specific T cells stimulated by hepatitis B virus(HBV)-specific proteins in chronic hepatitis B patients accepting antiviral therapy. Methods Seventeen patients with chronic hepatitis B (CHB) accepting antiviral therapy were included in this study. The peripheral blood monocular cell ( PBMC) were separated from the whole blood collected at the three different time of before and one and three months after accepting antiviral therapy. ELISPOT assay was used to detect the frequency and strength of secreting IFN-γ cells of PBMC stimulated by HBsAg, HBcAg and HBeAg. HBV virus loading, HBsAg, HBeAg, ALT and AST in serum were detected at the same time. Results After three months therapy, ALT, TBiL were improved in all patients, and HBV DNA level were dropped and undetectable in 11 cases. The rates of T cell response in patients to HBV specific proteins were 64. 7% , 76. 5% and 82. 4% at the time of before and one and three months after accepting antiviral therapy, respectively. The frequency of responses of antigen-specific T cells stimulated by HBcAg was higher than that stimulated by HBsAg or HBeAg, and the frequency was enhanced after antiviral therapy. The average response magnitude was expressed as spot forming cells (SFC) per million input cells. SFC of T cell responses to HBcAg was also higher than to HBsAg or HBeAg. There was no significant difference in SFC of T cell responses to HBsAg or HBeAg at the time of before and after antiviral therapy, but there were significant difference in SFC of T cell responses to HBcAg at the time of before and after antiviral therapy. SFC of T cell responses to HBcAg was negatively associated with HBV DNA, and no associated with level of ALT in serum. Conclusion The responses of antigen-specific T cells were improved in CHB patients accepting antiviral therapy which associated with the decrease of HBV DNA. It suggested to investigate HBV specific T cell responses was important. 
 
Key words: 
Chronic hepatitis B;  Cell immunity;  Antigen protein;  Antiviral therapy