Fig. 5

TGF-β-rich tumors sustain CD73 experssion on T cells to hinder anti-4-1BB therapy. a The expression levels of TGF-β were analyzed from single cell suspension of different tumor tissues by real-time RT-PCR. b The ability of anti-4-1BB treatment to reduce CD73⁺ subset in CD8⁺ tumor infiltrates was calculated across a variety of tumors. c The frequency of CD73⁺ subset in CD8⁺ tumor infiltrates was positively correlated with intratumoral expression levels of TGF-β. d The ability of anti-4-1BB treatment to reduce CD73⁺ subset in CD8⁺ tumor infiltrates was negatively correlated with intratumoral expression levels of TGF-β. e 4T1-bearing mice were treated as indicated. The tumor weight was measured 20 days after tumor challenge. f Survival curves of 4T1-bearing mice (5 mice per group). g Percentage of CD73⁺ in tumor-infiltrating CD4⁺ or CD8⁺ T cells in treated 4T1-bearing mice as indicated. h Percentage of CD4⁺, CD8⁺, or CD8⁺IFN-γ⁺ T cells among total CD45⁺ tumor infiltrates in treated 4T1-bearing mice as indicated. i Detection of IFN-γ⁺ cells among transferred CD8⁺ T cells in MC38-HS-bearing mice treated, and (j) representative flow dot plots. *p < 0.05, **p < 0.01, ***p < 0.001. Log-rank test and unpaired Student’s two-tailed t test were used. Data (mean ± SEM) are representative of 2 independent experiments with 5 independently analyzed mice/group