Interleukin-1β Maturation Triggers Its Relocation to the Plasma Membrane for Gasdermin-D-Dependent and -Independent Secretion
IL-1β requires processing by caspase-1 to generate the active, pro-inflammatory cytokine. Acute IL-1β secretion from inflammasome-activated macrophages requires caspase-1-dependent GSDMD cleavage, which also induces pyroptosis. Mechanisms of IL-1β secretion by pyroptotic and non-pyroptotic cells, an...
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Published in | Cell reports (Cambridge) Vol. 24; no. 6; pp. 1425 - 1433 |
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Main Authors | , , , , , , , , , , , , , |
Format | Journal Article |
Language | English |
Published |
United States
Elsevier Inc
07.08.2018
Elsevier |
Subjects | |
Online Access | Get full text |
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Summary: | IL-1β requires processing by caspase-1 to generate the active, pro-inflammatory cytokine. Acute IL-1β secretion from inflammasome-activated macrophages requires caspase-1-dependent GSDMD cleavage, which also induces pyroptosis. Mechanisms of IL-1β secretion by pyroptotic and non-pyroptotic cells, and the precise functions of caspase-1 and GSDMD therein, are unresolved. Here, we show that, while efficient early secretion of endogenous IL-1β from primary non-pyroptotic myeloid cells in vitro requires GSDMD, later IL-1β release in vitro and in vivo proceeds independently of GSDMD. IL-1β maturation is sufficient for slow, caspase-1/GSDMD-independent secretion of ectopic IL-1β from resting, non-pyroptotic macrophages, but the speed of IL-1β release is boosted by inflammasome activation, via caspase-1 and GSDMD. IL-1β cleavage induces IL-1β enrichment at PIP2-enriched plasma membrane ruffles, and this is a prerequisite for IL-1β secretion and is mediated by a polybasic motif within the cytokine. We thus reveal a mechanism in which maturation-induced IL-1β trafficking facilitates its unconventional secretion.
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•IL-1β cleavage by caspase-1 is both necessary and sufficient for IL-1β secretion•IL-1β maturation enables its relocation from the cytosol to the plasma membrane•Caspase-1 activity increases the speed of IL-1β secretion, via GSDMD•PIP2 membrane microdomains support GSDMD-dependent and -independent IL-1β exit
Interleukin-1β is a potent pro-inflammatory cytokine whose dysregulated production drives a myriad of human diseases. Monteleone et al. uncover the trafficking mechanisms driving the unconventional secretion of mature interleukin-1β in non-pyroptotic and pyroptotic myeloid cells and reveal functions for caspase-1 and GSDMD therein. |
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Bibliography: | ObjectType-Article-1 SourceType-Scholarly Journals-1 ObjectType-Feature-2 content type line 23 |
ISSN: | 2211-1247 2211-1247 |
DOI: | 10.1016/j.celrep.2018.07.027 |