Fig. 4.

Protection against NXS2 tumor challenge requires innate and adaptive cell-mediated immunity. a Schematic representation of the immunization schedule and depletion regimen. A/J mice were depleted of CD4⁺, CD8⁺ T cells or NK cells before and during NXS2 challenge and vaccination with the 47-LDA construct alone (b) or in combination with IL-15 and IL-21 vectors (c). Mice immunized with the sham vector alone or in combination with IL-15 and IL-21 served as a negative controls. Additional groups of mice that were immunized with the 47-LDA vaccine in the absence or presence of IL-15 and IL-21 and were treated with rat IgG antibodies served as positive controls. The mean tumor growth of the control mice that were treated with sham plasmid in the presence or absence of the cytokines genes 25 days after tumor challenge was considered as 100%. Bars, mean of experiments including 6–8 mice per group SD (error bars). * P < 0.01; ** P < 0.001; *** P < 0.0001