Figure 2.

HC003/VID 418—definition of CD4⁺ T-cell epitopes in HIV-1 protein Gag. Cryopreserved PBMC from vaccine recipient 418 were expanded by stimulation with ‘parental’ 15-mer responder peptide for 10 days to establish effector STCL. These were subjected to ICS using serially truncated (left) and a positive CD4⁺ T-cell production of IFN-γ (green) and TNF-α (orange) was monitored. Arrows and amino acids E, T and G indicate the peptide-terminal residues required for efficient peptide recognition.