Mimetic Hierarchical Approaches for Osteochondral Tissue Engineering.

Area of Science:

• Biomaterials Science
• Regenerative Medicine
• Tissue Engineering

Background:

• Engineering functional osteochondral (OC) constructs requires mimicking natural developmental processes for both cartilage and bone tissues.
• Hierarchical scaffolds with gradual physical, mechanical, and biochemical property changes are crucial for biomimetic OC tissue engineering (TE).
• Key components include cells, scaffolds, bioreactors, and controlled stimulation of developmental processes like mesenchymal condensation and vascularization.

Purpose of the Study:

• To provide an overview of biomimetic OC TE system components and fabrication methods for gradient scaffolds.
• To address challenges in achieving clinically relevant, anatomically shaped OC constructs.
• To cover applications beyond neotissue engineering, including disease/healing models and in vitro drug evaluation models.

Main Methods:

• Utilizing "smart" scaffolds for localized cell phenotype regulation.
• Employing dual-flow bioreactors to manage distinct cartilage and bone conditions.
• Incorporating strategies like mesenchymal condensation, vascularization, growth factor application, mechanical stimulation, purinergic signaling, low oxygen conditioning, and immunomodulation.

Main Results:

• Development of fabrication methods for gradient scaffolds in biomimetic OC TE.
• Strategies for stimulating mesenchymal condensation and vascularization components.
• Consideration of "smart" scaffolds and dual-flow bioreactors for controlled tissue development.

Conclusions:

• Biomimetic OC TE offers a promising approach for regenerating osteochondral tissues.
• The integration of advanced scaffolds, bioreactors, and controlled stimuli is essential for successful hierarchical graft engineering.
• This field holds potential for both clinical applications and the development of sophisticated in vitro models for research and drug testing.