Decellularized bone matrix/oleoyl chitosan derived supramolecular injectable hydrogel promotes efficient bone...

Area of Science:

• Biomaterials Science
• Tissue Engineering
• Regenerative Medicine

Background:

• Decellularized extracellular matrix (ECM) hydrogels are promising for bone regeneration but suffer from poor mechanical strength and rapid degradation.
• Developing robust and bioactive scaffolds is crucial for clinical translation in bone tissue engineering.

Purpose of the Study:

• To develop and evaluate a novel biohybrid hydrogel (DBM/OC) based on decellularized bone ECM (DBM) and oleoyl chitosan (OC) for enhanced bone regeneration.
• To assess the potential of DBM/OC hydrogel as a cell-delivery vehicle for human amnion-derived stem cells (HAMSCs).

Main Methods:

• Fabrication of DBM/OC biohybrid hydrogels and benchmarking against collagen-I/OC hydrogels.
• Characterization of hydrogel properties including morphology, rheology, mechanical strength, and antimicrobial activity.
• In vitro evaluation of HAMSCs encapsulation, proliferation, and differentiation within the hydrogels.
• In vivo assessment using chick chorioallantoic membrane (CAM) assay for neovascularization and subcutaneous implantation for immunogenicity.
• Evaluation of bone regeneration in a rabbit tibial defect model using micro-CT and histomorphological analysis.

Main Results:

• DBM/OC hydrogels exhibited improved mechanical strength and recapitulated a native nanofibrillar microenvironment.
• The hydrogels demonstrated antimicrobial properties and supported superior HAMSCs proliferation and differentiation.
• Ex vivo CAM assay showed excellent neovascularization potential, and in vivo implantation revealed minimal immune response.
• HAMSCs-loaded DBM/OC hydrogels significantly enhanced mature mineralized bone formation in rabbit tibial defects compared to controls.

Conclusions:

• The DBM/OC biohybrid hydrogel represents a promising osteoinductive scaffold with enhanced mechanical properties and cell-delivery capabilities.
• This novel biomaterial effectively promotes bone regeneration by supporting stem cell activity and vascularization.
• DBM/OC hydrogels hold significant potential for clinical applications in bone tissue engineering and regenerative medicine.