Fig 6. Cytotoxic killing of target cells loaded with HCV antigens-derived peptides, by splenocytes obtained from Ad vector immunized mice.
Splenocytes harvested from Ad vector immunized mice, were stimulated in vitro with the HCV protein antigens core, NS3, NS4 and NS5 at 5 μg/ml concentrations for 4 days. The target EL4 cells were incubated with corresponding HCV peptides each at 1 μg/ml concentration (core peptides #: 2, 14, 17, 25, 27, 28, 32; NS3 peptides #: 8, 10; NS4 peptides #: 3, 4, 8; NS5a peptides #: 1, 2, 16, 20 and NS5b peptides: 5, 19, 23, 39; or All: a mixture of the above peptides from core, NS3, NS4 and NS5) and peptide-loaded EL4 cells were cultured with effectors at 10:1 (effectors: target) ratio for 4–5 hours. Empty (no peptide loaded) EL4 targets were used as a negative control. CFSE-labeled live targets were quantified by flow cytometry, and % killed targets were calculated using the formula: % Killing = [(Average live cells in PBS control − live cells in immunized group) /Average live cells in PBS control] × 100). Data shown are mean±SD and are representative of three independent experiments.