FIG. 10.

Signaling pathways for NF-κB activation by IL-1β. Following the interaction of IL-1 with the type 1 IL-1 receptor, the NIK-IKK pathway can be activated through the MyD88, IRAK, and TRAF6 signaling proteins. Alternatively, Rac1 and Cdc42 can activate the NADPH oxidase complex and induce NF-κB activity through the production of ROIs. Other pathways involve, in lymphoid cells, the cytoplasmic phospholipase A2, the 5-LOX, and FLAP complex and the production of ROIs or, in epithelial cells, the acid sphingomyelinase (SMase) and the production of ceramide. CPLA2, cytosolic phospholipase A2.