Mechanically robust cryogels with injectability and bioprinting supportability for adipose tissue engineering

Area of Science:

• Biomaterials Science
• Tissue Engineering
• Regenerative Medicine

Background:

• Adipose tissue engineering offers an alternative to traditional methods for soft tissue reconstruction.
• Current challenges include creating a suitable microenvironment, maintaining volume stability, and achieving vascularization for long-term integration.
• Existing scaffolding materials and biofabrication techniques face limitations in recapitulating native adipose tissue characteristics.

Purpose of the Study:

• To develop robust, injectable, and stretchable cryogels for adipose tissue engineering.
• To assess the cryogels' ability to support adipose progenitor cell and mesenchymal stromal cell functions.
• To integrate cryogels with 3D bioprinting for fabricating vascularized, clinically relevant adipose constructs.

Main Methods:

• Fabrication of cryogels using methacrylated gelatin, methacrylated hyaluronic acid, and 4arm poly(ethylene glycol) acrylate (PEG-4A) via cryopolymerization.
• Evaluation of cryogel mechanical properties, injectability, and stretchability.
• Assessment of cell adhesion, proliferation, and adipogenic differentiation of human adipose progenitor cells (HWA) and adipose-derived mesenchymal stromal cells.
• Co-culture with human umbilical vein endothelial cells (HUVEC) to evaluate vascularization potential.
• Integration of cryogels with 3D bioprinting to create flap-like adipose constructs.

Main Results:

• The cryogels exhibited mechanical robustness, injectability, and stretchability, with PEG-4A enhancing mechanical properties.
• Cryogels supported HWA and adipose-derived mesenchymal stromal cell adhesion, proliferation, and adipogenic differentiation.
• HWA-laden cryogels promoted co-culture with HUVECs, leading to capillary-like network formation and enhanced adipogenesis.
• 3D bioprinting on cryogels produced integrated, handleable flap-like constructs with supported vascularization.

Conclusions:

• Cryogels provide a promising platform for volume-stable adipose tissue engineering.
• The combination of cryogels and 3D bioprinting offers a viable strategy for fabricating vascularized adipose constructs for complex soft tissue regeneration.
• These engineered constructs demonstrate potential for clinical applications in soft tissue augmentation and defect reconstruction.