Fig. 4

Tumor-derived EVs augmented the overexpression of CTLA-4 in CD8 + T cells. A Percentage and B representative figures of CTLA-4-expressing CD8 + T cells after incubation of EVs. C Representative flow cytometric figures of CTLA-4 expression (gated on CD8 + T cells) with EVs treated and D corresponding quantification of mean fluorescence intensity (MFI). E CTLA-4 gene expression of CD8 + T cells evaluated by quantitative PCR at 24 and 48 h. CTLA-4 genes were normalized to control. Data are representative of 3–4 independent experiments. Bar graphs reflect mean ± SEM (n = 5–6) analyzed by two-way ANOVA with Tukey’s post hoc test or Mann–Whitney U test (quantitative PCR). *, P < 0.05; **, P < 0.01; ***, P < 0.001; ****, P < 0.0001