Fig. 3: IOX1 mediates dendritic cell (DC) maturation, downregulates cancer cell PD-L1 expression, and promotes T cell proliferation and activity.

a–c DC maturation determined by (a) flow cytometry and (b) quantification of the mature DCs (CD11c⁺CD80⁺CD86⁺), and their secretion of (c) TNF-α and IL-6 in supernatants; CT26 cells were pre-treated with IOX1, DOX, their combination, PLD, or IPLD; DOX dose, 5 μM; IOX1 dose, 25 μM; 24 h; they were co-incubated with DCs for another 24 h; n = 3 independent experiments. d–f IOX1 downregulated the endogenous PD-L1 measured by (d) flow cytometry and (e) western blotting and quantification, and (f) the Cd274 mRNA levels analyzed by qPCR in the cells; CT26 cells were treated as indicated in (a–c) for 24 h; n = 3 independent experiments. g–j T cell (PBMC) proliferation and cytotoxic-activity after incubating with pre-treated CT26 cells: (g,h) flow cytometric profiles and their calculated proliferation indices (PIs) of T cells; i,j flow cytometric analysis and quantifications of the apoptotic CT26 cells with or without PBMCs co-culturing; CT26 cells were pre-treated as indicated in (a–c) for 24 h; the isolated cells were co-cultured with PBMCs in fresh medium for 3 days; the treated cells in fresh medium without PBMCs were cultured for comparison. n = 3 independent experiments. Data represent mean ± SD. Two-tailed Student’s t test. NS no significance; ** P < 0.01, *** P < 0.001, **** P < 0.0001. Source data are provided as a Source Data file.