IL1B and macrophage activation syndrome: The characteristics of the cytokine storm depend on the causative factor; however, in the case of MAS, several cytokines have been proposed to contribute towards cytokine storm development, with the inflammasome-derived cytokines interleukin-1 beta (IL-1β) and interleukin-18 (IL-18) being implicated in disease pathogenesis (Takada et al., 1999; Krei et al., 2021).