Bioprinted Injectable Hierarchically Porous Gelatin Methacryloyl Hydrogel Constructs with Shape-Memory Properties

Area of Science:

• Biomaterials Science
• Regenerative Medicine
• Tissue Engineering

Background:

• Direct injection of cell-laden hydrogels shows potential in tissue regeneration but often lacks structural control.
• Traditional methods for patterned cell-laden hydrogels require invasive surgery.

Purpose of the Study:

• To develop injectable, hierarchically porous cell-laden hydrogel constructs with enhanced structural controllability for tissue regeneration.
• To overcome limitations of traditional bulk fillers and invasive surgical procedures in cell-based therapies.

Main Methods:

• Encapsulation of living human cells in a pore-forming gelatin methacryloyl (GelMA)-based bioink.
• Fabrication of hierarchically macro-micro-nanoporous cell-laden GelMA hydrogel constructs using 3D extrusion bioprinting.
• Assessment of hydrogel construct properties including shape recovery, cell viability, proliferation, spreading, differentiation, and in vivo host tissue integration.

Main Results:

• 3D bioprinted GelMA hydrogel constructs exhibited tunable shapes and sizes for defect-specific applications.
• The hierarchically porous structures enabled excellent shape recovery after compression and injection.
• Sustained high cell viability, proliferation, spreading, and differentiation were observed post-injection.
• In vivo studies demonstrated successful integration of the hydrogel constructs with surrounding host tissues.

Conclusions:

• The developed 3D-bioprinted pore-forming GelMA hydrogel constructs offer a promising solution for minimally invasive tissue regeneration.
• These constructs provide structural controllability and support cellular functions, making them suitable for advanced cell therapy applications.
• The technology advances the field of injectable biomaterials for regenerative medicine and translational therapy.