Characterization of the T cells infiltrating enucleated primary UMs. (A) Example of CD4 versus CD8 expression in T (CD3⁺) cells in juxta and tumor sites. (B–E) Frequency of the indicated cell populations in juxta-tumor and tumor tissues. (D and E) Frequency of Tregs is defined as CD127⁻CD25⁺ (D) or CD25⁺FOXP3⁺ (E) in CD4⁺ T cells. (F) Frequency of CD8⁺ T cells expressing CD69, CD103, CD27, KLRG1, PD-1, TIM3, LAG3, and CD39 in juxta-tumor and tumor tissues (representative staining in Fig. S1 D). (G, H, and M) UMAP of flow cytometry data in five juxta-tumor and six primary tumors, gated in T cells. (G) UMAPs of color-coded surface expression of CD4, CD127⁻CD25⁺CD4⁺ (Treg), and CD8⁺ in CD3⁺ (left) and distribution of CD3⁺ cells from either juxta-tumor (light blue) or tumor sites (violet) (right). (H) UMAP of CD3⁺ cells color-coded for D3 (blue) or M3 (red) tumors. (I and J) Frequency of CD8⁺ T cells (I) and CD4⁺ T cells (J) in D3 and M3 tumors. (K) Example of CD127 versus CD25 staining of CD4⁺ T cells in D3 or M3 tumors. (L) Frequency of Tregs in D3 or M3 tumors (only samples with >10 CD4⁺ cells were considered). (M) UMAP of color-coded CD39 (left) and PD-1 (right) surface expression in CD3⁺ cells. (N) Example of PD-1 versus CD39 expression in CD8⁺ T cells from D3 and M3 tumors. (O) Frequency of CD8⁺ T cells expressing both CD39 and PD-1 in M3 and D3 tumors. (P) Distribution of PD-1⁺CD39⁺ in CD8⁺ T cells according to tumor T cell infiltration. Coh1 (n = 20) was used in A–C. Coh2 (n = 7) was used in E. Coh3 (n = 33) was used in D, F–N, and P. Coh1 and coh3 were used in O. Non-parametric paired Wilcoxon test was used in B–E. Non-parametric Mann–Whitney test was used in F, J, L, and O. Only P < 0.05 is shown.