Figure 9.

Inhibition of T cell recognition of EBNA1 by protein synthesis inhibitors. (A) Specific inhibition of M3-W1-B9 CD8⁺ T cell recognition of HEK293/B8/EBNA1-GFP target cells by an irreversible protein synthesis inhibitor emetine. HLA-B8–expressing HEK293/EBNA1-GFP target cells were treated with an emetine inhibitor at three concentrations for 1 h. After three washes, cells were cocultured with M3-W1-B9 CD8⁺ T cells overnight for IFN-γ release assays. Similar experiments were performed for the treatment of cells with cycloheximide or puromycin. To determine effect of emetine on recognition of MHC class I/EBNA1 peptide on the cell surface, we also pulsed HLA-B8⁺ 1359 cells with the EBNA1-P _518–526 peptide after the treatment of 1359mel cells with three different concentration of emetine. (B) Determination of the sensitivity of recognition of TRP2-specific CD8⁺ T cells to the treatment with emetine. 1363mel cells were treated with three different concentrations of emetine. After three washes, the cells were cocultured with TRP2-specific CD8⁺ T cells. The treated cells pulsed with a TRP2 peptide were used to examine the effect of emetine on recognition of MHC class I–TRP2 complexes on the cell surface.