Fig. 1.

Recruitment scheme, study protocol, and illustration of DC generation. a Tumor samples of patients with confirmed pancreatic carcinoma were stored for future vaccinations (step 1). In the follow-up phase (step 2), patients were monitored for recurrence of disease. After recurrence (or in case of a primary palliative situation), DC vaccination was initiated (step 3). b The vaccination protocol consisted of two vaccinations in the first month and subsequent monthly vaccinations. Immunological assays and staging CTs were performed after 2, 4, 6, and 12 months as indicated. c Adherent PBMC were cultured in the presence of IL-4 and GM-CSF for 6 days, then loaded with KLH and tumor lysate, resulting in cells termed immature DC. Maturation of DC was induced by stimulation with TNF-α and PGE2. Purity of tumor lysate-loaded DC was 89.63% in median (range 64.89 to 95.49%). Mature DC were CD14 negative (median 0.61%, range 0.18 to 8.18%), CD80 positive (median 84.48%, range 82.27 to 92.57%), CD83 positive (median 70.87%, range 51.37 to 83.69%), and expressed high levels of MHCII (median 97.02%, range 84.48 to 98.23%). d Stimulation with TNF-α and PgE2 led to an increase in IL-12 production. Error bars indicate SEM