Abstract
Interleukin (IL)-37 is a member of the IL-1 family of cytokines. Although its broad anti-inflammatory properties are well described, the effects of IL-37 on inflammasome function remain poorly understood. Performing gene expression analyses, ASC oligomerization/speck assays and caspase-1 assays in bone marrow-derived macrophages (BMDM), and employing an in vivo endotoxemia model, we studied how IL-37 affects the expression and maturation of IL-1β and IL-18, inflammasome activation, and pyroptosis in detail. IL-37 inhibited IL-1β production by NLRP3 and AIM2 inflammasomes, and IL-18 production by the NLRP3 inflammasome. This inhibition was partially attributable to effects on gene expression: whereas IL-37 did not affect lipopolysaccharide (LPS)-induced mRNA expression of Il18 or inflammasome components, IL-37-transgenic BMDM displayed an up to 83% inhibition of baseline and LPS-stimulated Il1b compared to their wild-type counterparts. Importantly, we observed that IL-37 suppresses nigericin- and silica-induced ASC oligomerization/speck formation (a step in inflammasome activation and subsequent caspase-1 activation), and pyroptosis (-50%). In mice subjected to endotoxemia, IL-37 inhibited plasma IL-1β (-78% compared to wild-type animals) and IL-18 (-61%). Thus, our study adds suppression of inflammasome activity to the portfolio of anti-inflammatory pathways employed by IL-37, highlighting this cytokine as a potential tool for treating inflammasome-driven diseases.
Original language | English |
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Article number | 178 |
Number of pages | 19 |
Journal | Cells |
Volume | 9 |
Issue number | 1 |
DOIs | |
Publication status | Published - 10 Jan 2020 |
Keywords
- AIM2
- ASC
- caspase-1
- inflammasome
- interleukin 18
- interleukin 1β
- interleukin 37
- NLRP3
- pyroptosis
Equipment
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MHTP Medical Genomics Facility
Wilson, T. (Manager)
Hudson Institute - Department of Molecular and Translational ScienceFacility/equipment: Facility
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Monash Micro Imaging (MMI)
Firth, S. (Manager), Fulcher, A. (Operator), Chernyavskiy, O. (Operator), Rzeszutek, M. (Other), Potter, D. (Manager), Hilsenstein, V. (Operator), Nunez-Iglesias, J. (Other), Cody, S. (Manager), Carmichael, I. (Operator), Kouskousis, B. (Other), Creed, S. (Manager) & Ballerin, G. (Operator)
Faculty of Medicine Nursing and Health Sciences Research PlatformsFacility/equipment: Facility