Mimicking osteochondral interface using pre-differentiated BMSCs/fibrous mesh complexes to promote tissue...

Area of Science:

• Biomaterials Engineering
• Tissue Engineering
• Regenerative Medicine

Background:

• Osteochondral tissue's complex structure necessitates implants with biomimetic gradients.
• Electrospun fibrous meshes offer a platform for creating gradient structures through layer-by-layer assembly.

Purpose of the Study:

• To construct a triphasic, gradient implant for osteochondral defect repair.
• To evaluate the efficacy of a biomimetic gradient implant in regenerating cartilage and subchondral bone.

Main Methods:

• Electrospun poly(L-lactide)/gelatin (PLLA/Gel) fibrous meshes were fabricated with tissue-specific components (hyaluronic acid, chondroitin sulfate, hydroxyapatite).
• Pre-differentiated bone marrow mesenchymal stromal cells (BMSCs) on PLLA/Gel meshes were induced using mixed osteoinductive/chondroinductive media.
• Layer-by-layer stacking of cell-seeded meshes created a triphasic gradient construct.

Main Results:

• The gradient construct, when implanted in rabbit knee osteochondral defects, led to effective regeneration of both cartilage and subchondral bone.
• The regenerated tissue exhibited a reproduced tidal line structure, indicating successful integration.
• The study confirmed the effectiveness of cell sheets on electrospun fibrous meshes for gradient construction.

Conclusions:

• Biomimetic gradient implants are crucial for successful osteochondral defect repair.
• Layer-by-layer stacking of cell sheets on electrospun fibrous meshes provides a flexible method for constructing gradient implants.
• The developed gradient construct shows significant potential for promoting osteochondral regeneration.