Injectable dual-gelling cell-laden composite hydrogels for bone tissue engineering

Area of Science:

• Biomaterials Science
• Regenerative Medicine
• Tissue Engineering

Background:

• Developing injectable hydrogels for bone regeneration is crucial.
• Mesenchymal stem cells (MSCs) are key for bone repair.
• Composite hydrogels offer tunable properties for cell delivery.

Purpose of the Study:

• To investigate the osteogenic potential of injectable, dual-gelling composite hydrogels for MSC delivery.
• To evaluate the in vitro and in vivo performance of these hydrogels for bone tissue engineering.

Main Methods:

• Fabrication of N-isopropylacrylamide-based hydrogels with gelatin microparticles (GMPs).
• In vitro assessment of MSC encapsulation, survival, and osteogenic markers.
• In vivo evaluation in a rat critical-sized cranial defect model.

Main Results:

• Hydrogels successfully encapsulated and maintained MSC viability in vitro.
• GMP incorporation enhanced mineralization and alkaline phosphatase production.
• In vivo, GMPs promoted bony bridging and mineralization; MSCs and GMPs facilitated tissue infiltration and osteoid formation.

Conclusions:

• Injectable, dual-gelling composite hydrogels support MSC delivery and bone regeneration.
• GMPs enhance osteogenesis and bone-implant integration.
• These hydrogels show significant potential for bone tissue engineering applications.