Fig. 3.

CD137 signal transduction into NPC cells. A 10⁵ C666 or C666-CD137 cells were cocultured at a 1:1 ratio with control or CD137L-expressing HEK-293T cells (CD137L). B–D 10⁴ control or CD137-expressing C666 (B), HONE-1 (C) or HK-1 (D) cells were seeded on BSA or rCD137L coated plates. After 3 days, cytokine concentrations in the supernatant were measured by ELISA. *p < 0.05; **p < 0.01, ns, non-significant, by two-tailed paired t-test ND: non-detectable. The data are representative of at least two independent experiments with comparable results. E Wells were coated with 5 µg/ml rhCD137L or PBS before 10⁵ C666-CD137 or HK-1-CD137 cells were added for 24 h, and analyzed assessed by flow cytometry. The histogram shows the signal gated on live single cells (F). Wells were coated with 5 µg/ml rhCD137L or PBS before 10⁵ C666-CD137 or HK-1-CD137 cells were seeded and incubated for 72 h with either 10 mM VX-702 or an equal volume of DMSO control. IL-8 was measured in the supernatant. Unpaired T test (F) and one-way ANOVA followed by multiple comparison test (F–G) were used for statistical analysis. At least three replicates are performed. *p < 0.05, ****p < 0.0001