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Updated: Jun 21, 2026
10:23
Evaluation of Caspase Activation to Assess Innate Immune Cell Death
Published on: January 20, 2023
Caspases regulate VAMP-8 expression and phagocytosis in dendritic cells
Yong Hou Sunny Ho1, Deyu Tarika Cai, Dachuan Huang
1Department of Microbiology, Laboratory of Membrane Trafficking and Immunoregulation, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 117597, Republic of Singapore.
Biochemical and Biophysical Research Communications
|July 18, 2009
Summary
Caspases regulate dendritic cell (DC) maturation by cleaving VAMP-8, a protein that inhibits phagocytosis. This process is crucial for antigen presentation during inflammation and pathogen encounters.
Area of Science:
- Immunology
- Cell Biology
Background:
- Immature dendritic cells (DCs) mature upon encountering pathogens, enhancing antigen presentation.
- DC maturation involves reduced caspase activity and inhibited phagocytosis.
- Caspases are key regulators of apoptosis, necrosis, and inflammation.
Purpose of the Study:
- To investigate the role of caspases in regulating VAMP-8 during DC maturation.
- To identify how VAMP-8 influences phagocytosis in DCs.
Main Methods:
- Demonstrated VAMP-8 as a caspase substrate.
- Identified caspase recognition sites on VAMP-8.
- Assessed phagocytosis in immature DCs treated with caspase inhibitors.
Main Results:
- VAMP-8 is cleaved by caspases.
- Two conserved caspase cleavage sites were identified on VAMP-8.
- Caspase inhibition led to VAMP-8 upregulation and reduced phagocytosis in immature DCs.
Conclusions:
- Caspases regulate VAMP-8 expression and activity.
- This regulation impacts phagocytosis during DC maturation.
- Highlights a novel mechanism controlling DC function in immune responses.
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