Vertical immunodominance of the HLA-Cw0801/Env171–180 T cell response. (A) PBMCs from two representative subjects with a documented history of acute hepatitis B were expanded in vitro with the HBV genotype C peptide library (15-mer peptides covering the full HBV core, envelope, and polymerase proteins) and screened using IFN-γ ELISPOT assays. Each bar shows the response against a pool of 15-mer peptides covering the corresponding HBV protein, and the single epitope responsible for the ELISPOT hits was confirmed by ICS and annotated accordingly. SFU counts shown were background subtracted and normalized to 10,000 cells. Pt1, patient 1; Pt2, patient 2. (B) PBMCs from 15 subjects with serological evidence of prior HBV infection (anti-HBs and anti-HBc positive) were expanded in vitro and screened as described above. Detailed responses from two representative subjects (R1 and R16) are shown (top). The vertical immunodominance of the HLA-Cw0801/Env171–180 T cell response is summarized in the table and pie chart (bottom).