Related Experiment Videos
Regulation of endothelial monocyte-activating polypeptide II release by apoptosis
U E Knies1, H A Behrensdorf, C A Mitchell
1Department of Molecular Cell Biology, Max-Planck-Institut für Physiologische und Klinische Forschung, Parkstrasse 1, 61231 Bad Nauheim, Germany.
Summary
Endothelial monocyte-activating polypeptide II (EMAP II) is a proinflammatory cytokine. This study reveals EMAP II processing coincides with apoptosis, attracting macrophages to clear dead cells during tissue remodeling.
Area of Science:
- Cell Biology
- Immunology
- Developmental Biology
Background:
- Endothelial monocyte-activating polypeptide II (EMAP II) is a proinflammatory cytokine.
- EMAP II attracts monocytes, key immune cells involved in tissue repair and inflammation.
- Apoptosis, or programmed cell death, is a critical process in development and tissue homeostasis.
Purpose of the Study:
- To investigate the role of EMAP II during embryonic tissue remodeling.
- To determine the relationship between EMAP II expression and apoptosis.
- To elucidate the mechanism of EMAP II processing and its function in attracting macrophages.
Main Methods:
- Analysis of EMAP II mRNA expression in mouse embryos using in situ hybridization.
- Detection of apoptotic cells via terminal deoxynucleotidyltransferase-mediated dUTP end labeling (TUNEL).
- Cell culture experiments to study pro-EMAP II processing and inhibition using peptide-based inhibitors.
Main Results:
- EMAP II mRNA was highly expressed at sites of embryonic tissue remodeling and apoptosis.
- Macrophages colocalized with areas of EMAP II expression and cell death.
- Pro-EMAP II processing to mature EMAP II occurred concurrently with apoptosis in cultured cells.
- A specific inhibitor blocked pro-EMAP II cleavage, suggesting caspase-like activity involvement.
Conclusions:
- The processing of EMAP II is linked to the apoptotic process.
- Activated caspase-like enzymes likely process pro-EMAP II during cell death.
- EMAP II acts as a crucial cytokine attracting macrophages to apoptotic sites, facilitating efficient clearance of dead cells during tissue remodeling.