Three dimensional extrusion printing induces polymer molecule alignment and cell organization within engineered...

Area of Science:

• Biomaterials Science
• Tissue Engineering
• Regenerative Medicine

Background:

• Effective cell-material interactions are crucial for successful tissue regeneration.
• Current methods for controlling cell behavior on scaffolds often require complex surface engineering.
• Articular cartilage regeneration requires specific zonal cell and collagen fiber orientation.

Purpose of the Study:

• To investigate if 3D extrusion printing can induce polymer molecule alignment, subsequently influencing cell alignment and differentiation.
• To evaluate the potential of this technique for creating cartilage tissue engineering scaffolds.
• To explore a simplified method for controlling cell-material interactions in tissue engineering.

Main Methods:

• Utilized 3D extrusion-based printing at high temperature and pressure.
• Employed small-angle X-ray scattering (SAXS) to confirm polymer molecule alignment.
• Assessed cellular response (morphology, orientation, gene expression) in vitro and in vivo using mesenchymal stem cells (MSCs).

Main Results:

• 3D printing induced significant polymer molecule alignment, which in turn directed MSC morphology and orientation.
• Gene expression analysis indicated improved superficial zonal chondrogenic markers in parallel-aligned scaffolds.
• Cell alignment was maintained in vivo for at least 7 days, showing distinct MSC morphology differences between printed and casted scaffolds.

Conclusions:

• 3D printing at high temperature/pressure can induce both polymer and cell alignment without complex surface treatments.
• This approach offers a new strategy for developing advanced scaffolds with controlled cell-material interactions for complex tissue engineering.
• The findings present a promising concept for effective tissue repair in future clinical applications.