Spatiotemporal Modulated Scaffold for Endogenous Bone Regeneration via Harnessing Sequentially Released Guiding...

Area of Science:

• Biomaterials Science
• Tissue Engineering
• Regenerative Medicine

Background:

• Effective bone regeneration requires scaffolds that mimic natural bone development.
• Regulating the sequential differentiation of bone marrow mesenchymal stromal cells (BMSCs) is crucial for mimicking endochondral ossification (ECO).

Purpose of the Study:

• To design and fabricate a dual-networked composite hydrogel scaffold (GCDH-M) for spatiotemporal control of BMSCs differentiation.
• To investigate the scaffold's ability to guide chondrogenesis, angiogenesis, and osteogenesis sequentially.

Main Methods:

• Fabrication of a dual-networked hydrogel (gelatin-hyaluronic acid) incorporating chondroitin sulfate (CS) and magnesium/silicon (Mg/Si) ions via PLGA microspheres.
• Utilizing covalent bonding and host-guest interactions for dynamic hydrogel properties.
• In vitro and in vivo evaluations of BMSCs differentiation and bone regeneration.

Main Results:

• The GCDH-M hydrogel demonstrated sequential release of CS and Mg/Si ions, guiding BMSC differentiation.
• The scaffold successfully promoted chondrogenic, hypertrophic, and osteogenic phenotypes in BMSCs.
• In vitro and in vivo studies confirmed the hydrogel's ability to create an optimal microenvironment for bone regeneration, aligning with ECO.

Conclusions:

• The developed GCDH-M composite hydrogel effectively mimics the ECO process for bone regeneration.
• This innovative scaffold design offers a promising approach for bone tissue engineering by providing sequential differentiation cues.