Phase IIb trial of in vivo electroporation mediated dual-plasmid hepatitis B virus DNA vaccine in chronic hepatitis B patients under lamivudine therapy

Table 4 Hepatitis B virus antigen-specific T-cell responses in 45 patients from week 50 to 70 after the trial n (%)

Positive response	Vacc. (n = 22)	Ctr. (n = 23)	P value
1IFN-γ secretion	19 (86.4)	13 (56.5)	0.047
2CD3 + CD8 + IFN-γ	17 (77.3)	10 (43.5)	0.021

¹A positive T-cell response was defined as an increase in interferon-γ (IFN-γ) secretion by two times compared to the control level, tested by ELISA, that in itself was no less than 100 pg/mL upon 9 d cultivation of PBMCs stimulated by HBsAg;

²A positive T-cell response was defined as no less than 0.1 percentage frequency of CD8 cells showing positive IFN-γ intracellular staining, tested by FACS, upon stimulation by various HBV envelope antigens. Vacc.: LAM + DNA vaccine arm; Ctr.: LAM + placebo arm.