Fig. 5

Changes in tumor infiltrating T cell frequencies upon mCD39-specific ASO treatment. Mice bearing homogenous MC38 tumors (between 50 and 80 mm³) were injected with CD39 ASO at indicated concentrations, or control oligo 1 (100 mg/kg) on days 1–5. On day 8 or 9 tumors were digested to isolate tumor infiltrating immune cells. Frequency of tumor infiltrating Tregs (live CD4⁺FoxP3⁺CD25⁺) (a) and non-Tregs (CD4⁺FoxP3⁻CD25⁻) (b) is indicated as percent of live CD45⁺ cells. (c) CD39 expression on Tregs is depicted against Treg frequency at the respective CD39 ASO doses. (d) Frequency of tumor infiltrating CD8⁺ cells was assessed in tumors of mice treated as per (a) and ratio of CD8⁺ cells to Tregs is depicted. (e) PD-1 expression (MFI) on tumor infiltrating CD8⁺ cells of CD39 ASO and control oligo 1 -treated mice was assessed by flow cytometry. Representative dot plots (middle) and overlapping histograms (right) depict the increase in PD-1 expression on CD8⁺ cells of CD39 ASO treated tumors compared to control oligo 1. In all cases each data point represents a mouse. Pooled data from two to three independent repeats. Error bars indicate SD. Asterisks indicate significant differences compared to control oligo 1 group