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Updated: Jun 26, 2026
05:18
Quantification of Immunostained Caspase-9 in Retinal Tissue
Published on: July 25, 2022
Caspase-8 is involved in neovascularization-promoting progenitor cell functions
Dörte Scharner1, Lothar Rössig, Guillaume Carmona
1Department of Internal Medicine III, University of Frankfurt, Frankfurt, Germany.
Arteriosclerosis, Thrombosis, and Vascular Biology
|January 6, 2009
Summary
Caspase-8 plays a critical role in endothelial progenitor cells (EPCs) function beyond apoptosis. This study reveals its importance in EPC survival, migration, and neovascularization, identifying Cbl-b as a key regulator.
Area of Science:
- Cell Biology
- Molecular Biology
- Regenerative Medicine
Background:
- Endothelial progenitor cells (EPCs) are crucial for therapeutic neovascularization post-ischemia.
- EPC survival and retention are vital for their proangiogenic potential.
- Caspases, known for apoptosis, may have other roles in cellular processes.
Purpose of the Study:
- To investigate the role of caspases in proangiogenic cells, specifically focusing on endothelial progenitor cells.
- To elucidate the non-apoptotic functions of caspases in EPCs.
Main Methods:
- Pharmacological inhibition of caspase-8 using zIETD.
- Analysis of EPCs from caspase-8-deficient mice.
- Assessment of EPC adhesion, migration, and in vivo neovascularization capacity.
- Evaluation of surface receptor expression (integrins, CXCR4) and identification of potential caspase-8 substrates (Cbl-b).
Main Results:
- Caspase-8 inhibition abrogated ex vivo EPC formation, adhesion, and migration.
- EPCs from caspase-8-deficient mice showed reduced neovascularization capacity.
- Caspase-8 inhibition decreased the expression of alpha5, beta1 integrins, and CXCR4.
- Cbl-b was identified as a potential substrate of caspase-8, regulating integrin and receptor signaling.
Conclusions:
- Caspase-8 has a novel, apoptosis-unrelated function in proangiogenic cells.
- Caspase-8 regulates EPC adhesion, migration, and homing via integrin and receptor modulation.
- These findings highlight caspase-8 as a potential therapeutic target for enhancing neovascularization.
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