Figure 5.

Lung cancer cell lines expressing CD137L induced T cell secretion of IFN‐γ to promote its own PD‐L1 expression. (a, c) HCC‐827 or 293FT* (transfected with CD137L plasmid) and T cells were cultured separately or cocultured in 96‐well plates, supplemented with or without anti‐CD3 mAb and anti‐CD137 mAb, and the supernatant was harvested 48 hours later to measure IFN‐γ. (b) The PD‐L1 expression of HCC‐827 was determined by flow cytometry after CHCC‐827 cultured alone or cocultured with T cells for 48 hours. (d) the 293FT* cells (open histograms) and the control cells nontransfected 293FT (shaded histograms) were detected by flow cytometry. Differences were considered significant at * P < 0.05, ** P < 0.01.