2.8. Flow cytometry

Cells were washed with cold PBS and stained with FITC-conjugated PD-L1 (or FITC isotype control) in 100 μL 0.2% bovine serum albumin at 4 °C for 2 h (5 μL/2 × 10⁵ cells). After washing with cold PBS, samples were detected by BD FACSuite TM (BD bioscience, USA). Tumor tissues were minced and separated into single-cell through a tissue dissociator (Miltenyi Biotec, USA). Cells were then stained with antibodies against CD3, CD8a and CD45 in 100 μL 0.2% bovine serum albumin at room temperature for 30 min (1 μL/2 × 10⁵ cells). Cells were washed with PBS and analyzed by flow cytometry. The data were analyzed by one-way ANOVA with Dunnett's post hoc test.