Figure 7

Cytokine flow cytometry analysis of the functional phenotype of pmel CD8⁺ splenocytes from IL-21 + IL-2 treated mice. Spleen cells were pooled from 2 mice with progressing tumors (≥ 50 mm²) and from 2 mice with regressing tumors (<10 mm²) 42 days after vaccination. Cytokine flow cytometry analysis shows the absolute number of pmel CD8⁺ T cells per 10⁶ splenocytes (A), and the frequency of pmel CD8⁺ cells (B) that are positive for IL-2, IFNγ, and TNFγ production. Data show mice with regressing tumors had 4.7-fold, 4.8-fold and 2.5-fold more IL-2⁺, IFN-γ⁺, and TNF-α⁺ pmel CD8⁺ T cells respectively, and higher frequencies of Tc1 cytokine⁺ cells than progressor mice.