FIG 6.

Endogenous processing of the Env_171–180 epitope from full-length HBV envelope protein. The HLA-Cw0801-expressing hepatocellular carcinoma cell line SNU-423 was transduced with the full-length HBV genotype C envelope gene. The transduced line was then used as a target to stimulate HLA-Cw0801/Env_171–180-specific short-term T cell lines, and activation was determined by intracellular cytokine staining for IFN-γ, TNF-α, and IL-2. The frequency of epitope-specific cytokine-producing lymphocytes was compared to that obtained using HLA-Cw0801-expressing EBV B cells pulsed with the Env_171–180 peptide as targets.