Fig. 1: Cell surface expression of PD-1, PD-L1, and CD80 in T cell subsets and LEC.

a–c Flow cytometry analysis of PD-1, PD-L1, and CD80 expression on FACS-sorted mouse Foxp3GFP^-CD44^lowCD25⁻CD4⁺ naïve CD4 or IL-2 + anti-CD3/28-stimulated activated Foxp3GFP⁻ CD25⁺CD4⁺ Teffs, Foxp3GFP⁺CD44^lowCD25⁺CD4⁺ tTregs or IL-2 + anti-CD3/28 + TGF-β1-induced Foxp3GFP⁺CD44^highCD25⁺CD4⁺ iTregs (a); human CD4⁺CD25^highCD127⁻CD45RA⁻ Tregs or CD4⁺CD25⁻CD127⁺CD45RA⁺ Teffs (b); or cultured or freshly isolated mouse LECs (Lyve-1⁺CD31⁺), mouse non-LECs (Lyve-1⁻CD31⁻) and cultured human LECs (c). ΔMFI, MFI of Ab staining minus isotype control staining. Mean ± SEM. *p < 0.001 by one-way ANOVA with Tukey’s multiple comparison test (a, c) and unpaired, two-tailed t-test with Welch’s correction (b). d Immunohistochemistry of PD-1 and PD-L1 expression and flow cytometry analysis of permeabilized LECs. Magnification ×60, scale bar 10 μm. Intracellular staining of PD-1 in LEC shown. Data representative of 3 (a–c) or 2 (d) independent experiments. Source data are provided as a Source Data file.