Microvascular fragment spheroids: Three-dimensional vascularization units for tissue engineering and regeneration

Area of Science:

• Regenerative Medicine
• Tissue Engineering
• Vascular Biology

Background:

• Adipose tissue-derived microvascular fragments (MVF) are crucial for vascularization in tissue engineering.
• Three-dimensional cell arrangements can improve cellular function and therapeutic potential.
• Previous studies utilized stromal vascular fraction (SVF) spheroids for regenerative applications.

Purpose of the Study:

• To generate and characterize microvascular fragment (MVF) spheroids for the first time.
• To investigate the enhanced vascularization potential of MVF spheroids.
• To compare the efficacy of MVF spheroids against SVF spheroids in regenerative medicine.

Main Methods:

• Generation of MVF spheroids from adipose tissue.
• Assessment of spheroid morphology, size, and viability.
• Quantification of endothelial (CD31) and perivascular (α-SMA) cells.
• Evaluation of angiogenic sprouting activity in vitro.
• In vivo transplantation and vascularization assessment in mouse dorsal skinfold chambers.

Main Results:

• MVF spheroids demonstrated comparable morphology, size, and viability to SVF spheroids.
• MVF spheroids contained significantly higher numbers of CD31-positive endothelial cells and α-SMA-positive perivascular cells.
• Enhanced angiogenic sprouting activity was observed in MVF spheroids.
• MVF spheroids exhibited improved in vivo vascularization and engraftment after transplantation.

Conclusions:

• MVF spheroids represent a superior vascularization unit compared to SVF spheroids.
• MVF spheroids hold significant promise for improving the vascularization of tissue defects.
• These findings support the use of MVF spheroids in tissue engineering and regenerative medicine.