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Screening Bioactive Nanoparticles in Phagocytic Immune Cells for Inhibitors of Toll-like Receptor Signaling
Published on: July 26, 2017
A combinatorial F box protein directed pathway controls TRAF adaptor stability to regulate inflammation
Bill B Chen1, Tiffany A Coon, Jennifer R Glasser
1Department of Medicine, Acute Lung Injury Center of Excellence, University of Pittsburgh, Pittsburgh, Pennsylvania, USA. chenb@upmc.edu
Nature Immunology
|April 2, 2013
Summary
A novel pathway involving Fbxo3 protein stimulates cytokine secretion, potentially causing tissue injury. Inhibiting Fbxo3 reduced inflammation in mouse models, offering therapeutic targets for critical illnesses.
Area of Science:
- Immunology
- Molecular Biology
- Biochemistry
Background:
- Uncontrolled activation of tumor necrosis factor receptor-associated factor (TRAF) proteins can lead to significant tissue damage.
- TRAF proteins link cell surface signals to the release of inflammatory cytokines.
Purpose of the Study:
- To investigate the role of Fbxo3 in regulating cytokine secretion and TRAF protein activity.
- To explore Fbxo3 as a potential therapeutic target for cytokine-driven inflammation.
Main Methods:
- Investigated the interaction between Fbxo3, Fbxl2, and TRAF proteins in human inflammatory cells.
- Analyzed circulating Fbxo3 and TRAF protein levels in sepsis patients.
- Utilized a small-molecule inhibitor of Fbxo3 in mouse models of inflammation.
Main Results:
- Fbxo3 destabilizes Fbxl2, a TRAF inhibitor, thereby stimulating cytokine secretion.
- Circulating Fbxo3 and TRAF levels correlated with cytokine responses in sepsis.
- A hypofunctional Fbxo3 polymorphism was identified in humans.
- Fbxo3 inhibition reduced inflammation severity in mouse models.
Conclusions:
- Fbxo3 is a key regulator of innate immunity by controlling TRAF protein abundance.
- Fbxo3 represents a potential biomarker for altered immune responses in critical illness.
- Targeting Fbxo3 offers a therapeutic strategy for managing cytokine-driven inflammation.
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