Three-dimensional printed collagen/chitosan scaffold improves neurological recovery after spinal cord injury in rats
10.3969/j.issn.2095-4344.2279
- Author:
Xin Yu SHI
1
Author Information
1. Graduate School of Tianjin Medical University
- Publication Type:Journal Article
- Keywords:
3D printing;
Chitosan;
Collagen;
MRI;
Neuroelectrophysiology;
Repair;
Scaffold;
Spinal cord injury
- From:
Chinese Journal of Tissue Engineering Research
2020;24(22):3474-3479
- CountryChina
- Language:Chinese
-
Abstract:
BACKGROUND: Three-dimensional (3D) printing technology can be used to prepare bioscaffolds to meet the requirements of shape, size and surface morphology of spinal cord implantation. OBJECTIVE: To investigate the effect of 3D printed collagen/chitosan scaffolds on the recovery of neurological function in rats with spinal cord injury. METHODS: The collagen/chitosan scaffolds were prepared by freeze-drying method with a mass ratio of 2:1. The 3D printed collagen/chitosan scaffolds were prepared by 3D printer. The porosity and elastic modulus of the scaffolds were measured, and the morphology of the scaffolds was observed by electron microscope. Neural stem cells were co-cultured with 3D printed collagen/chitosan scaffold, and common collagen/chitosan scaffold, respectively, for scanning electron microscope and cell counting kit-8 assay. Forty female Sprague-Dawley rats (provided by Academy of Military Sciences of PLA) were randomly divided into four groups: sham-operated, spinal cord injury, common collagen/chitosan scaffold, and 3D printed collagen/chitosan scaffold groups. The rats in the latter three groups were used to prepare complete spinal cord transected injury model, followed by filled with the corresponding scaffold materials. Basso, Beattie, Bresnahan scores of the posterior limb, slope test, neuroelectrophysiological detection and MRI were conducted at each time point after surgery. The study was approved by the Animal Ethics Committee of Tianjin Key Laboratory of Traumatic Brain Injury. RESULTS AND CONCLUSION: (1) Scanning electron microscope showed that 3D printed collagen/chitosan scaffolds had interconnected porous structure, and the internal structure of common collagen/chitosan scaffolds was disordered. (2) Neural stem cells grew well on the surface of scaffolds and fully extended. The activity of neural stem cells on the surface of 3D printed collagen/chitosan scaffolds was significantly higher than that of the common collagen/chitosan scaffold group (P < 0.05). (3) The porosity and modulus of elasticity in the 3D printed collagen/chitosan scaffold group were higher than those in the common collagen/chitosan scaffold group (P < 0.05). (4) The Basso, Beattie, Bresnahan score in the 3D printed collagen/chitosan scaffold group was higher than that in the spinal cord injury and common collagen/chitosan scaffold groups (P < 0.05) at 3-8 weeks after surgery, and the angle of slope experiment at 4, 6 and 8 weeks after surgery was higher than that in the spinal cord injury and common collagen/chitosan scaffold groups (P < 0.05). (5) The amplitude of motor evoked potential and somatosensory evoked potential in the 3D printed collagen/chitosan scaffold group were higher than those in the spinal cord injury and common collagen/chitosan scaffold groups (P < 0.05), and the latency of motor evoked potential and somatosensory evoked potential were shorter than those in the spinal cord injury and common collagen/chitosan scaffold groups (P < 0.05). (6) MRI plain scan showed that the amplitude of motor evoked potential and somatosensory evoked potential in the 3D printed collagen/chitosan scaffold group were higher than those in the spinal cord injury and common collagen/chitosan scaffold groups (P < 0.05). 3D printed collagen/chitosan scaffold group had good continuity and more nerve fiber bundles passing through the injury site. (7) The results imply that 3D printed collagen/chitosan scaffolds can promote the repair of nerve function in the spinal cord injury rats.
