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Updated: Jul 15, 2026
06:52
Detection of Inflammasome Activation and Pyroptotic Cell Death in Murine Bone Marrow-derived Macrophages
Published on: May 21, 2018
Caspase-1 processes IFN-gamma-inducing factor and regulates LPS-induced IFN-gamma production
T Ghayur1, S Banerjee, M Hugunin
1BASF Bioresearch Corporation, Worcester, Massachusetts 01605-4314, USA. ghayur@biovax.dnet.basf-ag.de
Nature
|April 10, 1997
Summary
Interleukin-18 (IGIF) maturation requires caspase-1, a protease also involved in IL-1beta production. Caspase-1 inhibition or deficiency reduces inflammatory cytokine production, suggesting new anti-inflammatory drug targets.
Area of Science:
- Immunology
- Molecular Biology
- Cytokine Signaling
Background:
- Interferon-gamma-inducing factor (IGIF, also known as interleukin-18 or IL-18) is a cytokine that induces interferon-gamma (IFN-γ) production.
- IGIF is synthesized as an inactive precursor (proIGIF) and requires proteolytic processing for activation.
- Interleukin-1beta (IL-1β) production also involves precursor cleavage by caspase-1.
Purpose of the Study:
- To investigate the role of caspase-1 in the maturation of proIGIF.
- To determine if caspase-1 is involved in the physiological production of IGIF and IFN-γ.
- To explore the potential of caspase-1 as a therapeutic target for inflammatory diseases.
Main Methods:
- In vitro processing assays using purified proIGIF and proIL-1β with caspase-1.
- Inhibition of caspase-1 activity in human mononuclear cells stimulated with lipopolysaccharide (LPS).
- Assessment of IFN-γ production in caspase-1-deficient mice stimulated with LPS.
Main Results:
- Caspase-1 efficiently processed both proIGIF and proIL-1β in vitro.
- A selective caspase-1 inhibitor blocked LPS-induced production of IL-1β and IFN-γ in human cells.
- Caspase-1-deficient mice showed impaired LPS-induced IFN-γ production.
Conclusions:
- Caspase-1 plays a critical role in the physiological maturation of IGIF (IL-18).
- Caspase-1 is essential for the production of multiple pro-inflammatory cytokines, including IL-1β and IGIF.
- Targeting caspase-1 with specific inhibitors offers a potential strategy for developing novel anti-inflammatory therapies.
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