Figure 4.

The enhanced effects of celecoxib (CXB) and anti-PD-1 mAb (αPD-1) on decreasing the presence of intratumoral Tregs, MDSCs, and PD-L1 positive tumor cells. C57BL/6 mice received the treatments with the blank hydrogel (gel) and the hydrogels delivering CXB (+ CXB), anti-PD-1 mAb (+ αPD-1), or both (+ CXB + αPD-1) at Day 7 after the inoculation of 1.0 × 10⁵ B16-F10 cells. Single-cell suspensions made from digested tumor tissues were subject to flow cytometric analyses 7 days after the treatments. (A) The representatives flow cytometric analysis images (left) and the corresponding quantification (right) of FoxP3⁺ analyses of CD4⁺ T cells. (B) The ratios of IFNγ⁺CD8⁺ T cells to Tregs. Each column represents three independent experiments (n = 6–8 animals per group per experiment). (C) The representative flow cytometric analysis images (left) and the corresponding quantification (right) of MDSCs (CD11b⁺Gr-1⁺) in CD45⁺ cells. (D) The ratios of IFN-γ⁺CD8⁺ T cells to MDSCs. (E) The representative flow cytometric analysis images (left) and the corresponding quantification (right) of PD-L1 analyses within the CD45⁻ cells. Each column represents three independent experiments (n = 8–12 animals per group per experiment). *P < 0.05, **P < 0.01, N.S., not significant, Student's t-tests. The asterisk or “N.S.” without a line underneath indicates the comparison to the blank hydrogel group. Error bars represent the standard error of the mean.