Native extracellular matrix/fibroin hydrogels for adipose tissue engineering with enhanced vascularization.

Area of Science:

• Biomaterials Science
• Tissue Engineering
• Regenerative Medicine

Background:

• Adipose tissue engineering requires vascularized scaffolds to support cell viability and nutrient/oxygen diffusion in thick implants.
• Biocompatible scaffolds with suitable mechanical properties are crucial for successful adipose tissue regeneration.

Purpose of the Study:

• To develop thick, vascularized adipose tissue constructs using decellularized adipose tissue (DAT) and silk fibroin (Fib) hydrogels.
• To evaluate cell viability, differentiation, and vascularization within DAT:Fib hydrogels for adipose tissue engineering.

Main Methods:

• Hydrogels were fabricated by mixing DAT and Fib at various v/v ratios (3:1, 1:1, 1:3).
• Adipose-derived stem cells (ASCs) were pre-differentiated into pre-adipocytes and pre-endothelial cells and encapsulated within the hydrogels.
• In vitro and in vivo subcutaneous implantation studies were conducted to assess cell behavior and vascularization.

Main Results:

• The 1:3 DAT:Fib hydrogel ratio exhibited mechanical properties similar to native adipose tissue.
• Hydrogels with a 1:3 DAT:Fib ratio supported superior cell viability, adipogenic differentiation (lipid vesicle formation), and endothelial cell tube formation.
• In vivo studies demonstrated rapid vascularization between weeks 1-2 post-implantation in hydrogels containing differentiated ASCs.

Conclusions:

• The 1:3 DAT:Fib hydrogel formulation provides a promising scaffold for adipose tissue engineering.
• Enhanced vascularization and sustained cell differentiation within the hydrogel support its potential for regenerating soft tissue defects.