Fig. 4.

ELISPOT analysis of tumor-reactive T cells. a To validate ELISPOT analysis, T cells were stimulated with unloaded or lysate-loaded DC. Only after 7 days of coculture and an additional 24-hour restimulation with lysate-loaded DC, IFN-γ-specific T cells could be observed. b The antitumor immune response of patient 52, treated with gemcitabine plus oxaliplatin, in the course of vaccination was examined by measuring the T cell response to tumor lysate 0, 17, 23, 34, 54, and 68 weeks after start of DC vaccination by ELISPOT assay. c Tumor-reactive T cells of a representative patient (54) receiving concomitant gemcitabine therapy before and after vaccination were quantified by ELISPOT assay. Error bars indicate SEM. Asterisks indicate P ≤ 0.05 in Student’s t test, in a in comparison to the unloaded situation, in b in comparison to IFN-γ production at week 0