Activation of interleukin‐ 1β by a co‐induced protease

Abstract
The proteolytic generation of mature interleukin- 1β (IL-1β) from its inactive precursor does not proceed by a conventional pathway for hormonal processing. Pro-IL- 1β is found dispersed in the cytoplasm, and there are no basic amino acid residues or other commonly recognized processing sites adjoining the mature N-terminus. Processing appears to occur during release of the hormone. In the present study, we have identified a specific protease that generates mature IL- 1β from the precursor. This enzyme is co-induced with the hormone, and it differs in its cleavage specificity and inhibitor sensitivity from all known proteases.