Fig. 2.

Combination of anti-CTLA-4 with systemic IT delays contraction and prolongs the activation of the protective CD8 response. a Schema depicting treatment regimen. Briefly, mice were treated with rIgG or anti-CD40 on days 0–4. PBS or high-dose IL-2 was administered on days 1, 4, 8, 11. Hamster IgG (hmIgG) or anti-CTLA-4 (UC10) was administered every other day beginning on day 7 and ending on day 17. Mice (n = 3-4 mice/group) were treated with control (rIgG/PBS) or IT (40/2) with either hamster IgG (hmIgG) or anti-CTLA-4 (UC10) as per the regimen in 2A and evaluated for T cell phenotype and function on various time points post-therapy. b Percentage and c numbers of CD8+ T cells on days 11, 18, and 25 following treatment. d Representative dot plots of splenic CD8 T cells based on CD62L and CD44 expression. Percentages of various memory CD8 populations on e) day 11 and f day 18 of therapy. g Lytic ability of splenic CD8 T cells on indicated day of treatment. Data are representative of 2–3 independent experiments. Statistical analysis was performed using two-way ANOVA with Bonferroni’s post-test. *p < 0.05, **p < 0.01, ***p < 0.001