Comparison of the Regenerative Effect of Adipose Tissue Mesenchymal Stem Cell Encapsulated into Two Hydrogel Scaffolds on Spinal Cord Injury

Background: Spinal cord injury (SCI) is a severe neurological disease leading to poor quality of life. Objectives: The regenerative effect of adipose-derived mesenchymal stem cells (AD-MSCs) encapsulated into fibrin, and collagen hydrogel scaffolds on a rat model of SCI was investigated using clinical and histopathological examinations. Methods: A total of 18 adult male Wistar rats (250 - 300 g) were prepared and randomly divided into three equal groups, each with six rats, including the control or SCI group (SCI contusion model without treatment), SCI contusion model treated with AD-MSCs encapsulated in fibrin hydrogel, and SCI contusion model treated with AD-MSCs encapsulated in collagen hydrogel groups. Clinically, functional recovery or hindlimb locomotor activity was assessed using Basso, Beattie, and Bresnahan's (BBB) scoring system four weeks post-treatment. The rats were sacrificed at week four post-treatment, and their spinal cords were examined histopathologically. Results: Faster functional recovery indicated with hindlimb locomotor activity was seen in both treatment groups compared to the control group. Severe polio and leuko-myelomalacia associated with disruption of spinal cord structure were identified in the control group. Mild polio and leuko-myelomalacia associated with mild to moderate disruption of spinal cord structure were seen in the collagen hydrogel + AD-MSCs and fibrin hydrogel + AD-MSCs groups. Conclusions: AD-MSCs encapsulated into fibrin and collagen hydrogels, as two of the most promising ECM-based or natural scaffolds have the potential to be developed in neural tissue engineering (NTE), such as for the treatment of SCI.