4-1BB/4-1BBL Interaction Promotes Obesity-Induced Adipose Inflammation by Triggering Bidirectional Inflammatory Signaling in Adipocytes/Macrophages

Figure 2

4-1BB or 4-1BBL stimulation enhances release of various inflammatory cytokines from adipocytes or macrophages. 3T3-L1 adipocytes and Raw264.7 macrophages were treated with 1 μg/mL 3E1 and 100 ng/mL r4-1BB Fc, respectively, for 48–24 h. MCP-1, TNF-α, IL-6, and IL-10 transcripts and proteins were then measured in the 3T3-L1 adipocytes (a-b) and Raw264.7 macrophages (c-d). The phosphorylation of IKKα/β (p-IKKα/β)/IKKβ, IκBα, p-p38, p-JNK/JNK, pAkt/Akt and β-actin were measured by western blotting. 3T3-L1 adipocytes were incubated with 1μg/mL 3E1 for 3 h (e), and Raw264.7 macrophages with 100 ng/mL r4-1BB Fc for 1 h (f). Results of densitometry were showed as percentage of control. Data are the mean ± SEM of three independent experiments performed in duplicate. ^∗𝑃<0.05; ^∗∗𝑃<0.01; ^#𝑃<0.005; ^##𝑃<0.001 (compared with control).