CD40-B loaded with FluMP mRNA induce functional specific T cells in pediatric oncology patients. (A) CD40-B from neuroblastoma patients were electroporated with FluMP mRNA or GFP mRNA and cocultured with autologous PBMC for 7 days. T-cell cultures were analyzed with tetramers as in Figure 2. (B) Day 7 T-cell cultures stimulated with FluMP mRNA-loaded CD40-B were assayed by IFN-γ ELISPOT using T2 cells pulsed with tax peptide or FluMP peptide (shown compared with T cells only). (C) T-cell cultures stimulated with FluMP mRNA or GFP mRNA were assayed for lysis of peptide-loaded T2 cells (left panel: • or ○, T2 cells loaded with FluMP peptide; ▪ or □, T2 cells loaded with tax peptide; • or ▪, FluMP mRNA–stimulated T cells; ○ or □, GFP mRNA–stimulated cells) or for lysis of SW-480 tumor cells (right panel: or ▴, SW-480 cells loaded with FluMP mRNA; ⋄, SW-480 loaded with GFP mRNA; or ⋄, FluMP mRNA–stimulated T cells; ▴, GFP mRNA–stimulated T cells). Similar results were obtained with 2 patients.