FIG 2.

Natural and engineered CD8 T cells are activated by HLA-A2-transduced Huh7.5 cells presenting exogenously pulsed cognate HCV epitope peptides. HCV-specific CD8 T cells specific for well-defined HLA-A2-restricted HCV NS3-1073 or NS5B-2594 epitopes were expanded from natural HCV resolvers (nT cells) (A) or engineered from seronegative donor by lentiviruses expressing HCV-specific T cell receptors (eT cells) (B), as shown by MHC/peptide tetramer (Tet) staining (left panels) as well as peptide-specific activation with CD107a mobilization and/or MIP-1β expression upon exposure to Huh7.5A2 cells pulsed exogenously with cognate peptides in vitro (right panels). To stimulate HCV-specific CD8 T cells, Huh7.5A2 cells were seeded overnight at 1 × 10⁵ cells in a 48-well plate or 2 × 10⁵ cells in a 24-well plate, pulsed with or without 10 μM cognate peptide for 1 h, and washed 3 times before the addition of 1 × 10⁵ nT or eT cells. After 6 h of coculture, CD8 T cells were collected, washed, stained, and analyzed by FACS. Numbers in the FACS plots indicate the frequency of the parent for gated cells.