MSC differentiation on two-photon polymerized, stiffness and BMP2 modified biological copolymers

Area of Science:

• Biomaterials Science
• Tissue Engineering
• Regenerative Medicine

Background:

• Bone tissue regeneration necessitates a 3D environment that supports cell growth and differentiation.
• Ideal scaffolds mimic native tissue structure and mechanics while incorporating growth factors.
• Two-photon polymerization (2PP) enables the fabrication of 3D scaffolds with micrometer precision.

Purpose of the Study:

• To design and fabricate 3D scaffolds using 2PP from biocompatible methacrylated D,L-lactide-co-ε-caprolactone copolymers (LC).
• To evaluate the proliferation and differentiation of bone marrow mesenchymal stromal cells (BMSCs) on LC scaffolds compared to a standard UDMA matrix.
• To investigate the effect of biomimetic, layer-by-layer surface functionalization, including stiffness modification and BMP2 incorporation, on BMSC osteogenic differentiation.

Main Methods:

• Utilized 2PP to create 3D scaffolds with controlled porous architecture from LC copolymers.
• Cultured BMSCs on LC scaffolds and a UDMA matrix, analyzing cell proliferation and differentiation markers.
• Applied layer-by-layer polyelectrolyte coatings to functionalize scaffold surfaces, modifying stiffness and incorporating BMP2.

Main Results:

• BMSCs exhibited optimal proliferation on LC scaffolds with pore sizes between 60-100 μm, maintaining Vimentin expression.
• Polyelectrolyte multilayer coatings significantly enhanced BMSC proliferation and differentiation, indicated by increased Osteonectin expression.
• Surface functionalization, particularly stiffness modification and BMP2 integration, proved crucial for improved osteogenic outcomes.

Conclusions:

• LC scaffolds fabricated via 2PP provide a promising 3D platform for bone regeneration.
• Biofunctionalization strategies, including stiffness tuning and BMP2 delivery, significantly enhance osteogenic differentiation of BMSCs.
• The combination of 3D design and biofunctionalization in LC scaffolds holds potential for future regenerative applications.