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Updated: Jun 25, 2025
08:41
Visualization of Inflammatory Caspases Induced Proximity in Human Monocyte-Derived Macrophages
Published on: April 6, 2022
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Caspase-5: Structure, Pro-Inflammatory Activity and Evolution
Leopold Eckhart1, Heinz Fischer2
1Department of Dermatology, Medical University of Vienna, 1090 Vienna, Austria.
Biomolecules
|May 24, 2024
Summary
Caspase-5, a protease, triggers inflammation by forming inflammasomes in response to lipopolysaccharide (LPS). This process is crucial for defense against Gram-negative bacteria and may play a role in sepsis.
Area of Science:
- Immunology
- Molecular Biology
- Microbiology
Background:
- Caspase-5 is a protease activated by lipopolysaccharide (LPS), a Gram-negative bacterial component.
- Its expression significantly increases upon LPS exposure, unlike other caspases.
Purpose of the Study:
- To review the structural features and regulatory mechanisms of caspase-5.
- To explore the evolutionary aspects of pro-inflammatory caspases in mammals.
- To discuss the role of caspase-5 in bacterial defense and sepsis.
Main Methods:
- Literature review focusing on caspase-5 structure, function, and evolution.
- Comparative analysis of caspase-5 and related caspases (e.g., caspase-4, caspase-11).
Main Results:
- Caspase-5 forms non-canonical inflammasomes upon intracellular LPS binding.
- Activated caspase-5 cleaves gasdermin D, leading to pore formation and cytokine release.
- Interspecies differences in caspase evolution, particularly between humans and mice, were highlighted.
Conclusions:
- Caspase-5 plays a key role in initiating inflammatory responses to Gram-negative bacteria.
- Understanding caspase-5's evolution and regulation is vital for studying sepsis and host defense.
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