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Detection of Inflammasome Activation and Pyroptotic Cell Death in Murine Bone Marrow-derived Macrophages
Published on: May 21, 2018
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GTPase Rab11b and effector Rab11-FIP2 promote NLRP3 stability during inflammasome priming
Caroline S Gravastrand1, Maria Yurchenko1, Stine Kristensen1
1Centre of Molecular Inflammation Research, Department of Clinical Molecular Medicine, Norwegian University of Science and Technology, Trondheim, Norway.
The EMBO Journal
|March 26, 2026
Summary
Rab11b and Rab11-FIP2 stabilize NLRP3 (NOD-, LRR-, and pyrin domain-containing protein 3) and pro-IL-1β during inflammasome priming. This pathway involves TAK1 and IKKβ, facilitating NLRP3 transport and activation in human macrophages.
Area of Science:
- Immunology
- Cell Biology
- Molecular Biology
Background:
- The NLRP3 inflammasome is crucial for innate immunity and inflammatory responses.
- Membrane trafficking, particularly through the trans-Golgi network, influences NLRP3 inflammasome activation.
- Rab GTPases regulate vesicular transport, but their specific roles in inflammasome priming remain incompletely understood.
Purpose of the Study:
- To investigate the role of Rab11 GTPases and their effector Rab11-FIP2 in NLRP3 inflammasome priming and activation.
- To elucidate the molecular mechanisms by which Rab11b and Rab11-FIP2 regulate NLRP3 stability and trafficking.
Main Methods:
- Utilized human macrophage models.
- Investigated protein-protein interactions using binding assays.
- Assessed protein stabilization and phosphorylation.
- Tracked protein translocation using microscopy.
Main Results:
- Rab11b and Rab11-FIP2 stabilize NLRP3 and pro-IL-1β during inflammasome priming.
- Rab11-FIP2 promotes TAK1 phosphorylation and subsequent IKKβ activation, crucial for NLRP3 translocation to the trans-Golgi network.
- NLRP3 and Rab11-FIP2 interact via their PI4P-binding domains.
- Rab11-FIP2 stabilizes NLRP3 on early endosomes, facilitating ASC speck formation.
Conclusions:
- Rab11b and Rab11-FIP2 are key regulators of NLRP3 inflammasome priming by controlling NLRP3 stability and trafficking.
- These findings reveal a novel mechanism linking membrane trafficking to inflammasome activation in human macrophages.
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