Figure 3. Comparison of antitumor activity with anti-CD25 antibodies.

a&b. Comparison of antitumor activity against pre-established tumors. C57BL/6 or BALB/c mice were inoculated s.c. with B16-OVA (a) or A20 (b) tumor cells (2.5×10⁵) and three days later were immunized with 1 ×10⁶ OVA-pulsed siGFP-DC or siA20-DCs ex vivo matured with LPS twice at a weekly interval, followed by in vivo polyI:C stimulation i.p. after each DC immunization. Anti-CD25 antibodies (100 ng/mouse) were administered into some groups of mice twice on days 1 and 5 prior to DC immunization. Tumor growth curves (n=6 mice/group) represent one of two repeated experiments. P < 0.01, siGFP-DC compared with siA20-DC.

c&d. Comparison of antigen-specific T cell responses. CD8⁺ (c) and CD4⁺ (d) T-cells isolated from the pooled splenocytes of different groups of mice (2-3/group) immunized with OVA-pulsed transduced DCs with or without in vivo anti-CD25 antibody administration were subjected to IFNγ ELISPOT assays in vitro restimulated with OT-I or OT-II peptide-pulsed DCs (10 μg/ml). *P < 0.01, vs. siA20-DC.