Serial intravital imaging captures dynamic and functional endothelial remodeling with single-cell resolution

Area of Science:

• Vascular Biology
• Cellular Dynamics
• Microscopy Techniques

Background:

• Endothelial cells are crucial for blood vessel health and disease.
• Studying endothelial precursor origin and dynamics in vivo at the single-cell level is challenging due to technical limitations.

Purpose of the Study:

• To develop a direct visual approach for tracking single endothelial cell fate and function in vivo.
• To investigate endothelial cell remodeling and repair in the kidney glomerulus using multiphoton microscopy.

Main Methods:

• Utilized transgenic Cdh5-Confetti mice for multicolor fluorescent protein expression.
• Employed multiphoton microscopy (MPM) for in vivo tracking of individual endothelial cells in the kidney glomerulus.
• Induced experimental hypertension, hyperglycemia, and laser ablation to study endothelial cell responses.

Main Results:

• Identified and tracked endothelial lineage cells by unique color combinations.
• Observed rapid increases in new glomerular endothelial cells in same-color clusters under disease conditions, suggesting local clonal expansion.
• Detected distinct structural and functional alterations in proliferating endothelial cells.
• Found no circulating Cdh5-Confetti+ cells in the renal cortex.
• Demonstrated significant clonal endothelial cell expansion in heart, lung, and kidneys compared to other organs.

Conclusions:

• Serial MPM of Cdh5-Confetti mice is a powerful tool for studying endothelial remodeling and repair.
• The study provides insights into the origin and dynamics of endothelial precursors in vivo.
• This technique advances the understanding of vascular repair mechanisms under physiological and disease conditions.