Structurally defined cartilaginous MEW-assembloids for critical-size long bone healing
Liuqi Peng1, Amit Chandrakar2, Gabriella Nilsson Hall1
1Prometheus, The Leuven R&D Translational Division of Skeletal Tissue Engineering, KU Leuven, O&N1, Herestraat 49, PB 813, 3000, Leuven, Belgium; Skeletal Biology and Engineering Research Center, Department of Development and Regeneration, KU Leuven, O&N1, Herestraat 49, PB 813, 3000, Leuven, Belgium.
Biomaterials
|February 23, 2025
Summary
This study introduces MEW-assembloids, combining Melt electrowriting (MEW) scaffolds with microtissues, to heal critical-sized bone defects. These novel constructs demonstrated significant new bone formation and defect bridging in preclinical models.
Area of Science:
- Biomaterials Science
- Tissue Engineering
- Regenerative Medicine
Background:
- Critical-sized bone defects lack spontaneous healing, necessitating advanced regenerative strategies.
- Current treatments like autografts and synthetic implants have limitations including donor site morbidity and poor integration.
- Novel approaches are needed to overcome challenges in bone defect repair and regeneration.
Purpose of the Study:
- To develop and evaluate Melt electrowriting (MEW)-assembloids for enhanced bone healing.
- To investigate the efficacy of MEW-assembloids in promoting endochondral ossification and mineralization.
- To assess the potential of MEW-assembloids as an innovative solution for critical bone defect regeneration.
Main Methods:
- Fabrication of bucket-shaped MEW scaffolds (OMesh and CMesh) for microtissue retention.
- Development of elongated MEW (EMesh)-assembloids for in vivo evaluation.
- Assessment of subcutaneous implants for endochondral ossification and mineralization.
- Orthotopic implantation of EMesh-assembloids with tubular MEW stabilizers in a critical-sized mouse tibia defect model.
Main Results:
- The OMesh design demonstrated effective shape retention after microtissue seeding.
- EMesh-assembloids underwent endochondral ossification and mineralization in subcutaneous implants.
- Orthotopic implantation showed substantial new bone formation and nearly full defect bridging within 8 weeks.
- Tubular MEW scaffolds acted as effective stabilizers for the assembloids.
Conclusions:
- MEW-assembloids represent a robust strategy for tissue engineering applications in bone regeneration.
- These constructs enhance the structural and functional integration of implants for bone repair.
- MEW-assembloids offer an innovative solution for regenerating critical bone defects, with potential clinical implications.
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