Interleukin-1 beta (IL-1β) is induced by inflammatory signals in a broad number of immune cell types. IL-1β (and IL-18) are the only cytokines which are processed by caspase-1 after inflammasome-mediated activation. IL-1 signaling activates innate immune cells including antigen presenting cells, and drives polarization of CD4 T cells towards T helper type (Th) 1 and Th17 cells.