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Updated: May 12, 2026
07:36
Isolation of Human Lymphatic Endothelial Cells by Multi-parameter Fluorescence-activated Cell Sorting
Published on: May 1, 2015
Lymphatic endothelium forms integrin-engaging 3D structures during DC transit across inflamed lymphatic vessels
Alvaro Teijeira1, Saray Garasa, Rafael Peláez
1Department of Oncology, Center for Applied Medical Research, Pamplona, Spain.
The Journal of Investigative Dermatology
|March 27, 2013
Summary
Under inflammation, dendritic cells (DCs) use ICAM-1 enriched microvilli to migrate into lymphatic vessels. This integrin-dependent process facilitates immune cell trafficking and response initiation.
Area of Science:
- Immunology
- Cell Biology
- Endothelial Biology
Background:
- Dendritic cell (DC) transmigration across lymphatic endothelium is crucial for immune responses.
- While DC transit is integrin-independent under noninflammatory conditions, inflammation involves integrins and their ligands.
Purpose of the Study:
- To investigate the role of ICAM-1 and microvilli in DC transmigration across lymphatic endothelium during inflammation.
- To elucidate the mechanisms underlying DC adhesion and migration into inflamed lymphatic vessels.
Main Methods:
- In vitro imaging of DC-lymphatic endothelial cell (LEC) interactions.
- Analysis of ICAM-1 accumulation on microvilli during inflammation.
- Investigation of the dependence of microvilli formation on β-integrins and integrin affinity.
- Assessment of CCL21's role in microvilli assembly using neutralizing antibodies.
Main Results:
- ICAM-1 (CD54) formed enriched three-dimensional structures on LEC/DC contacts during inflammation.
- ICAM-1 accumulated on microvilli projections surrounding adhered DCs in inflamed conditions, unlike noninflammatory states.
- ICAM-1-enriched microvilli promoted DC transendothelial migration and crawling.
- Microvilli formation depended on DC β-integrins and integrin-ligand affinity.
- LEC microvilli structures were found near CCL21 depots and their assembly was partially inhibited by CCL21-neutralizing antibodies.
Conclusions:
- Under inflammatory conditions, integrin ligands form 3D membrane projections (microvilli) around DCs.
- These structures serve as docking sites facilitating DC transit from tissues into lymphatic vessels.
- This mechanism is vital for immune surveillance and response initiation.
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