Visualization of live endothelial cells ex vivo and in vitro

Area of Science:

• Vascular Biology
• Cell Biology
• Histology

Background:

• Visualizing the vascular endothelium is crucial for understanding tissue structure and function.
• Existing methods for endothelial cell visualization can be complex or require fixed tissues.
• There is a need for rapid, live-cell imaging techniques for endothelial networks.

Purpose of the Study:

• To present simple, effective methods for visualizing the vascular endothelium in living human tissues and cell cultures.
• To demonstrate the utility of fluorescently conjugated Ulex Europaeus Agglutinin I (UEA-1) as a vital stain for endothelial cells.
• To enable detailed observation of vascular architecture and endothelial cell behavior in vitro and in situ.

Main Methods:

• Direct labeling of fresh human uterine and subcutaneous gluteal fat tissues with fluorescent UEA-1.
• Microscopic examination using conventional epi-illuminescence and confocal microscopy.
• Generation of 3D rendered surface models from confocal z-stacks.
• Utilizing UEA-1 for pre-labeling and verification of endothelial cells in primary cultures.
• Incorporating UEA-1 into a co-culture model for dynamic observation of endothelial cell phenotype.

Main Results:

• UEA-1 successfully visualized the three-dimensional vascular network in human uterine and fat tissues.
• Detailed microvascular architecture, including branch points and anastomoses, was clearly observed.
• Confocal z-stack analysis and 3D modeling confirmed the presence of microvessel lumens.
• UEA-1 facilitated the identification and verification of endothelial cells during culture isolation.
• Live observation of endothelial cell phenotype changes was achieved in a co-culture model.

Conclusions:

• Fluorescently labeled UEA-1 provides a quick and effective vital marker for endothelial cells.
• These techniques allow for detailed visualization of vascular networks in both intact human tissues and cell cultures.
• UEA-1 is valuable for studying angiogenesis, vascular structure, and endothelial cell behavior in various biological contexts.