Fig. 6: PD-1 and CD80 blockade result in CD25-Treg and Teff accumulation in TILs, reduction in dLNs, and tumor regression.

a–c In vivo footpad migration assays. a mAb-treated iTregs (left panel) or Teffs (right panel). b mAb pretreated footpads receiving iTregs (left) or Teffs (right). c untreated footpads receiving WT and PD-1^−/− iTregs. 1 × 10⁶ cells transferred, and the migrated cells (CFSE+) enumerated as the percentage of total CD4 T cells in popliteal dLNs. d–g B16F10-Fluc/eGFP tumor-bearing C57BL/6 mice treated with 5 mg/kg mouse weight of anti-PD-1 (Rmp1-14), anti-CD80 (1G10), or isotype rat IgG (2A3). Scheme of tumor treatment (d). Tumor growth curve (e). 8 mice/group; *p < 0.05, Two-way ANOVA, Holms-Šidák correction for multiple comparisons. Representative dot plots (f) and frequencies (g) of Foxp3⁺CD25⁺CD4Tregs, Foxp3⁺CD25⁻CD4 Tregs, and Foxp3⁻CD25⁺CD4 Teffs in total CD4 T cells of tumor-infiltrating lymphocytes (TILs) and of draining LNs (dLNs) or non-draining control LNs (non-dLNs) analyzed by flow cytometry. f, g Three to four mice/group. Data representative of 3 (a–c, f, g) and 2 (e) independent experiments. Mean ± SEM. *P < 0.05 by one-way ANOVA. Source data are provided as a Source Data file.