Composite Fibrin/Carbon Microfiber Implants for Bridging Spinal Cord Injury: A Translational Approach in Pigs

Area of Science:

• Biomedical Engineering
• Neuroscience
• Regenerative Medicine

Background:

• Spinal cord injury (SCI) poses significant challenges for neural repair.
• Biomaterials offer potential for enhancing neural regeneration after SCI.
• Large animal models are crucial for translating SCI therapies to clinical use.

Purpose of the Study:

• To evaluate the efficacy of fibrin gel-based biomaterial implants containing biofunctionalized carbon microfibers (MFs) in a porcine SCI model.
• To investigate the impact of myelotomy and lesion debridement on neural repair.
• To assess the potential of MFs/fibrin gel for bridging spinal cord cavities and promoting axonal regeneration.

Main Methods:

• Development of a porcine contusion/compression SCI model using an automated device.
• Performance of dorsal myelotomy and lesion debridement one day post-injury.
• Implantation of fibrin gel with biofunctionalized carbon microfibers into the lesion site.
• Histological and functional assessments of neural regeneration and tissue response.

Main Results:

• Myelotomy and debridement did not worsen neural damage but showed limited benefit for neural regrowth.
• The MFs/fibrin gel implant promoted axonal sprouting, elongation, and alignment within the lesion.
• The implant increased lesion volume and did not prevent fibrosis, hindering functional neural regeneration.

Conclusions:

• Myelotomy and lesion debridement are viable for implanting MF-based scaffolds in SCI.
• Current MF-based implants require significant refinement.
• Future strategies must incorporate pharmaceuticals to mitigate scarring and enhance functional neural recovery after SCI.