Bone Tissue Engineering with Multilayered Scaffolds-Part II: Combining Vascularization with Bone Formation in...

Area of Science:

• Biomaterials Science
• Tissue Engineering
• Regenerative Medicine

Background:

• Multilayered scaffolds with angiogenic, osteogenic, and osteoconductive layers promote vascularization and bone formation.
• Previous studies demonstrated through-the-thickness vascularization in acellular constructs without exogenous endothelial cells.

Purpose of the Study:

• To evaluate the vascularization and bone formation potential of acellular and cellular multilayered scaffolds in critical-sized rat calvarial defects.
• To compare the efficacy of acellular versus cellular constructs in promoting functional bone regeneration.

Main Methods:

• Implantation of acellular and cellular multilayered scaffolds into critical-sized rat calvarial defects.
• Quantification of vascularization and bone formation using microcomputed tomography (microCT) and MICROFIL perfusion.
• Histological evaluation at 4 and 12 weeks to validate microCT findings.

Main Results:

• Acellular multilayered scaffolds demonstrated comparable vascularization and bone regeneration to cellular constructs in critical-sized calvarial defects.
• Microscale-thick nanofibers and porous ceramic discs within the scaffolds facilitated functional vasculature and bone formation.
• Histological and microCT analyses confirmed significant bony bridging and union.

Conclusions:

• Bioengineered acellular multilayered scaffolds can effectively regenerate functional vasculature and bone.
• Acellular constructs represent a promising and potentially more translational approach for in vivo bone regeneration compared to cellular constructs.