Figure 2.

IL-1B signalling. IL-1B is produced as pro-peptide and activated by cleavage upon cell stimulation by PAMPs and DAMPs, as response mechanism to invading pathogens and cellular stress caused by sterile danger signals. IL-1B is functionally activated upon cleavage by caspase-1, which in turn, is activated by the NLRP3 inflammasome complex. After cleavage and activation, IL-1B is released by the cell, according to a poorly understood mechanism that comprehends both active and passive processes, including pyroptosis. Once released, IL-1B activates IL-1R1 receptor. Downstream signalling activation through Myd88, IRAKs and TRAF6 leads to NFKB-mediated transcription of pro-inflammatory cytokines and initiation of inflammation.