Figure 6

Induction of viral antigen-specific CD8⁺ T cell responses. As described previously, short-term and long-term cultured IL-15 DCs were matured using two different maturation cocktails (cc-mDC: TNF-α, IL1β, IL-6 and PGE₂; TLR-mDC: R-848, IFN-γ, TNF-α and PGE₂). Conventionally matured IL-4 DCs were used as a control (control IL-4 DCs). The mDCs were harvested, pulsed with a pool of cytomegalovirus-, Epstein-Barr virus- and influenza a virus (CEF)-derived peptides, and cocultured with autologous PBLs for 7 days. Viral antigen-specific CD8⁺ T cell responses were determined after this 7-day period and a short restimulation with the CEF peptide pool (CEF; filled bars). As specified in "Methods", the antigen-specific production of IFN-γ was assessed using two techniques: (a) ELISA to detect the amount of IFN-γ produced after restimulation (pg/mL) and (b) ICS to determine the % of IFN-γ⁺ CD8⁺ T cells. The non-specific IFN-γ release in response to restimulation with an irrelevant HPV peptide pool is shown (HPV; unfilled bars). Results are expressed as mean ± SEM of three independent experiments (*, P = 0.03; **, P = 0.006; ***, P < 0.001).