Biofabricating the vascular tree in engineered bone tissue.

Area of Science:

• Biomaterials Science
• Regenerative Medicine
• Tissue Engineering

Background:

• Native bone possesses a dense vascular network essential for development and homeostasis.
• Large bone defects necessitate bone substitutes due to limited patient-derived bone availability.
• A key challenge in bone tissue engineering is achieving adequate vascularization for nutrient and oxygen supply to engineered constructs.

Purpose of the Study:

• To review state-of-the-art biofabrication achievements in developing vascular networks for bone tissue engineering.
• To highlight strategies for creating multi-scale vasculature mimicking native bone's hierarchical structure.
• To provide insight into technologies for generating clinically relevant-sized vascularized bone constructs.

Main Methods:

• Review of current literature on biofabrication techniques for vascular network creation.
• Focus on 3D bioprinting and other advanced fabrication methods.
• Analysis of strategies for integrating macro- and micro-vessels in engineered constructs.

Main Results:

• Biofabrication enables the creation of complex, multi-scale vascular channels.
• 3D bioprinting facilitates the generation of hollow structures resembling blood vessels.
• Convergence of materials, cell types, and fabrication approaches shows promise for vascularized bone constructs.

Conclusions:

• Overcoming the vascularization bottleneck is critical for upscaling bone tissue engineering.
• Advanced biofabrication techniques are paving the way for clinically applicable vascularized bone substitutes.
• The development of functional, integrated vascular networks is imperative for successful bone regeneration.