Peptide-specific CTL responses induced in vivo (patient no. 8) by MUC1 peptide-pulsed DCs.

DCs were pulsed with the synthetic peptides derived from MUC1 and incubated with PBMNCs obtained before (C, D) or after 3 vaccinations with M1.2 and M1.1 peptides (A and B, respectively, ▪) to assess a MHC class I-restricted CTL response in vitro. Cytotoxic activity of induced CTLs was determined after one restimulation in a standard ⁵¹Cr-release assay using MCF-7 (HLA-A2⁺/MUC1⁺, ●) and T-2 (HLA-A2⁺) cells as targets pulsed for 2 hours with 25 μg of the cognate peptide (▪) or irrelevant HIV peptide (■). Control targets included K562 cells (▴), Croft cells (▿), and SK-OV-3 cells (○).