Figure 4

Effect of Ilantide on tumor necrosis factor α release from interleukin 1β-activated macrophages. AMJ2-C8 macrophages were exposed to interleukin 1β (IL-1β) and treated with Ilantide peptides, control peptides, IL-1 receptor antagonist (IL-1Ra) or soluble IL-1RI (sIL-1RI) for 24 hours. The conditioned medium from macrophages was used to treat fibroblast cells for 24 hours, and the amount of tumor necrosis factor α (TNF-α) in the conditioned medium was evaluated on the basis of fibroblast cell survival in the presence of actinomycin D. (A) TNF-α release from IL-1β-activated macrophages was inhibited by IL-1Ra. (B) TNF-α release from IL-1β-activated macrophages was inhibited by sIL-1RI. (C) TNF-α release from IL-1β-activated macrophages was inhibited by Ilantide-t. (D) TNF-α release from IL-1β-activated macrophages was inhibited by Ilantide-m. (E) Scrambled (scr) or reverse sequence control peptides did not inhibit TNF-α release from IL-1β-activated macrophages. The results from four independent experiments are expressed as percentage ± SEM with untreated controls set at 100%. *P < 0.05, **P < 0.01 and ***P < 0.001 compared with macrophages treated with IL-1β only (one-way analysis of variance followed by Newman-Keuls post hoc test).