Immunomodulatory activity of TFP-F1. J774A.1 macrophage cells were incubated for 24 h with or without different concentrations of TFP-F1 or LPS (1 μg/mL). (a) Induction of TNF-α secreted by TFP-F1 (5, 10, and 20 μg/mL) in J774A.1 macrophage cells. (b,c) Wild-type RAW-DualTM cells and RAW-DualTM KO-TLR4 cells were incubated with or without different concentrations of TFP-F1 (1, 3, and 5 μg/mL) or LPS (1 μg/mL). The levels of (b) TNF-α and (c) IL-6 in the RAW-DualTM KO-TLR4 cells. (d,e) Wild-type HEK293 cells and TLR4-expressing HEK 293 cells were incubated for 24 h with or without different concentrations of TFP-F1 (1, 3, and 5 μg/mL) or LPS (1 μg/mL), and the level of (d) TNF-α and (e) IL-6 were measured by ELISA.