Biomimetic 3D Hydrogels with Aligned Topography for Neural Tissue Engineering.

Area of Science:

• Biomaterials Science
• Neuroscience
• Regenerative Medicine

Background:

• Spinal cord injury (SCI) causes irreversible damage to neural cytoarchitecture.
• Current treatments lack strategies for effective axon regeneration after SCI.
• Hydrogels serve as biomaterial scaffolds for central nervous system (CNS) interfaces.

Purpose of the Study:

• To develop a reproducible method for creating aligned fibrils within 3D hydrogel matrices.
• To investigate the potential of these aligned hydrogels for neural regeneration after SCI.
• To evaluate the in vitro and in vivo efficacy of biomimetic hydrogels in supporting axon growth.

Main Methods:

• Utilized a collagen type I (Col)-based thermally gelling hydrogel system with laminin I (LN) and hyaluronic acid (HA).
• Employed an aspiration and ejection technique to create hydrogels with consistently aligned fibrils.
• Conducted in vitro studies with embryonic spinal cord neurons and in vivo implantation in a rat SCI model (T7/T8 dorsal hemisection).

Main Results:

• Thermally gelling hydrogels (Col, Col LN, Col HA) demonstrated consistent gelation at 37 °C.
• In vitro, spinal cord neurons survived and extended processes aligned with the collagen fibrils.
• In vivo, aligned hydrogels supported neurite growth along the direction of the aligned fibrils within the implant.

Conclusions:

• Thermally gelling biomimetic hydrogels can be fabricated into aligned matrices using aspiration and ejection.
• Aligned hydrogel scaffolds show potential for promoting neural regeneration and axon growth after SCI.
• This approach offers a novel platform for developing regenerative therapies for CNS injuries.