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Updated: Apr 12, 2026
Isolation of Human Umbilical Vein Endothelial Cells and Their Use in the Study of Neutrophil Transmigration Under Flow Conditions
Published on: August 8, 2012
[Investigation on the internalization pathway of microparticles into human umbilical cord endothelial cells]
Xiao-Juan Wei1, Hong-Chao Zhang2, Zheng-Zheng Shen3
1The fourth Military Medical University, Xi'an 710032.
Objective:
To investigate the mechanisms underlying the incorporation of microparticles(MP) derived from human bone marrow mesenchymal stem cells (MSCs) into human umbilical cord endothelial cells (HUVECs).
Methods:
MPs were isolated from the supernatants of MSCs which had exposed to a hypoxia/serum-deprivation condition. Electron microscope was used to identify the MPs. The surface molecule profile was evaluated with the bead-based flow cytometry technique. The expression level of the phosphatidylserine receptor (PSR) was detected by immunofluorescence cytochemistry. MPs were co-cultured with HUVECs in the presence or absence PSR-antibody, and the internalization of MPs was observed with laser scanning microscopy.
Results:
The MPs derived from MSCs expressed highly PS, while PSR expressed on the surface of HUVECs. The confocal result revealed that MPs could quickly be uptaken by the endothelial cells, and mainly distributed in the cytoplasm surrounding of the nuclei. The internalization of MPs reduced significantly after PSR specific blockage.
Conclusion:
The reaction between PS on the MP and the PSR of HUVECs plays an important role in the internalization of MSC-MPs.
Insights
Human bone marrow mesenchymal stem cell microparticles (MSCs) are incorporated into endothelial cells via a phosphatidylserine (PS) and phosphatidylserine receptor (PSR) interaction. This mechanism is crucial for microparticle uptake by cells.
Area of Science:
- Cell Biology
- Biotechnology
- Regenerative Medicine
Background:
- Mesenchymal stem cells (MSCs) are crucial in regenerative medicine.
- Microparticles (MPs) are released by cells and mediate intercellular communication.
- Understanding MP uptake mechanisms is vital for therapeutic applications.
Purpose of the Study:
- To elucidate the mechanism of human bone marrow MSC-derived MP internalization into human umbilical cord endothelial cells (HUVECs).
Main Methods:
- MPs were isolated from hypoxic/serum-deprived MSCs.
- MP characterization using electron microscopy and flow cytometry.
- HUVEC co-culture with MPs, with and without phosphatidylserine receptor (PSR) antibody, observed via laser scanning microscopy.
Main Results:
- MSCs-derived MPs express high levels of phosphatidylserine (PS).
- HUVECs express PSR on their surface.
- MP internalization by HUVECs was significantly reduced upon PSR blockade, indicating PSR's role.
Conclusions:
- The interaction between PS on MSC-MPs and PSR on HUVECs is a key mechanism for MP internalization.
- This PS-PSR interaction is critical for MSC-MP uptake by endothelial cells.
