A 4D printed self-assembling PEGDA microscaffold fabricated by digital light processing for arthroscopic articular...

Area of Science:

• Biomaterials Science
• Tissue Engineering
• Regenerative Medicine

Background:

• Articular cartilage has limited self-regeneration capacity, necessitating advanced repair strategies.
• Current treatments for focal cartilage defects often only postpone joint replacement.
• Tissue engineering offers an in situ approach using injectable, cell-laden scaffolds for cartilage reconstruction.

Purpose of the Study:

• To design and evaluate 3D-printed, self-assembling microscaffolds for osteochondral cartilage repair.
• To assess scaffold performance in a simulated cartilage defect model.
• To determine the feasibility of chondrocyte integration and survival within the biomaterial.

Main Methods:

• Design and 3D-printing of millimetre-scale, micro-patterned poly(ethylene glycol) diacrylate (PEGDA) microscaffolds.
• Assessment of scaffold coverage and self-assembly in simulated chondral lesions using various designs and delivery solutions.
• In vitro evaluation of chondrocyte engraftment, survival, and tissue formation within the microscaffolds.

Main Results:

• Hexagonal microscaffolds (750 μm x 300 μm) achieved 73.3% coverage of a model cartilage lesion when delivered with a 1% methyl cellulose solution.
• Chondrocytes successfully engrafted into the PEGDA biomaterial via a collagen hydrogel.
• Chondrocytes survived for at least 14 days in vitro, indicating potential for stratified cartilaginous tissue reconstruction.

Conclusions:

• A 4D-printed, injectable microscaffold system shows promise for in situ osteochondral tissue engineering.
• The developed hexagonal microscaffolds and delivery method are effective for cartilage defect coverage.
• This technique presents a viable strategy for future clinical applications in cartilage repair.