Fig. 1

Immunologic properties of MC-C and LMM3 tumors. (A): Vaccinating capacity of dendritic cells (DC) stimulated in vitro with MC-C or LMM3 lysates. 2 × 10⁵ DC were inoculated in the footpad of mice 14 and 7 days before the s.c. challenge with different doses of tumor cells. The vaccinating capacity was measured as an increase of tumor dose 50 (TD₅₀) of tumors in vaccinated mice compared to control mice. Data represent the mean ± SEM of two independent experiments. In each experiment, 20–25 mice per group were utilized. Similar results were obtained when lethally-irradiated tumor cells were used as a vaccination strategy. (B): Expression of cell-surface receptors CD80, CD86, and MHCII in DC stimulated with tumor lysates, evaluated by flow cytometry. Controls were unstimulated DC (DCi). DC stimulated with lysate of normal spleen cells (NSC) displayed similar results to that obtained with DCi, and, for simplicity, they were omitted. MFI = Mean fluorescence intensity. Data represent the mean ± SEM of two independent experiments. (C, D): Concentration of TNF-α (C) and IL-12p70 (D) (pg/ml) in supernatants of DC stimulated with MC-C or LMM3 tumors lysates. Data represent the mean ± SEM of three independent experiments. (E) Concentration of danger signals HGMB1 and Hsp 60 (pg/ml) in MC-C and LMM3 tumors lysates and in a NSC lysate. Each value represents the mean ± SEM of three assays. (F) Concentration of cytokines IL-10 and TGF-ß in MC-C and LMM3 tumors lysates. Levels of IL-10 and TGF-ß in NSC were undetectable. Each value represents the mean ± SEM of three assays. ELISA assays evaluated cytokines and danger signals levels. Statistical comparison between: experimental groups vs. DCi: # p < 0.05; ## p < 0.01; ### p < 0.001. Statistical comparison among the experimental groups:* p < 0.05; ** p < 0.01; *** p < 0.001.