Elastomeric Fibrous Hybrid Scaffold Supports In Vitro and In Vivo Tissue Formation

Area of Science:

• Biomaterials Science
• Tissue Engineering
• Biomedical Engineering

Background:

• Biomimetic materials are crucial for tissue engineering, needing biomechanical properties similar to native tissues.
• Mechanical anisotropy is a key feature of cardiovascular tissues, influencing their function.
• Existing methods often lack control over construct architecture and cell distribution.

Purpose of the Study:

• To fabricate anisotropic, cell-seeded constructs with controlled architecture and cell distribution.
• To develop a hybrid scaffold combining a poly-4-hydroxybutyrate (P4HB) fibrous material with encapsulated mesenchymal stem cells (MSCs).
• To evaluate the in vitro and in vivo performance of the developed scaffold for soft-tissue engineering.

Main Methods:

• Fabrication of an elastomeric fibrous scaffold using poly-4-hydroxybutyrate (P4HB) via dry spinning.
• Encapsulation of mesenchymal stem cells (MSCs) within a photocrosslinkable hydrogel to create hybrid scaffolds.
• In vitro culture of cellularized scaffolds in a cyclic stretch/flexure bioreactor.
• In vivo implantation of the hybrid scaffold as a patch in the pulmonary artery.

Main Results:

• The P4HB scaffold allowed control over fiber diameter, porosity, and degradation rate.
• Cyclic mechanical stimulation in a bioreactor promoted tissue formation within the hybrid scaffolds.
• In vivo implantation demonstrated the scaffold's ability to withstand physiological pressures.
• Aligned tissue formation was observed on the scaffold's luminal surface without significant thrombus formation.

Conclusions:

• The developed anisotropic fibrous scaffold combined with encapsulated MSCs promotes 3D tissue formation.
• This composite scaffold offers a biologically functional platform for soft-tissue engineering applications.
• The study presents a promising biomimetic approach for cardiovascular tissue repair and regeneration.