The interleukin-1 (IL-1)-like cytokine IL-33 is widely assumed to undergo proteolytic maturation by caspase-1. In this issue of Immunity, Lüthi et al. (2009) show that IL-33 is not a caspase-1 substrate. IL-33 is inactivated by caspase-3 and -7 to prevent an inappropriate immune response during apoptosis, but not in necrosis. © 2009 Elsevier Inc. All rights reserved.
Lamkanfi, M., & Dixit, V. M. (2009, July 17). IL-33 Raises Alarm. Immunity. https://doi.org/10.1016/j.immuni.2009.06.011