Regulation of the Maturity of Dental Pulp-Derived Induced Neural Cells by Cell-Recognizing Cadherin-Fc Chimeric Antibody Improved Neurological Function after Cell Implantation in a Mouse Traumatic Brain Injury Model

Biomaterial-based neural cell transplantation has displayed promise in regenerative medicine. E-cadherin and N-cadherin are cell-cell adhesion proteins with important roles in neuronal maturity. Therefore, cell culture on Petri dishes coated with a fusion protein combining the human E-cadherin or N-cadherin extracellular domain with an immunoglobulin G Fc region chimeric antibody (E-cad-Fc and N-cad-Fc) can regulate cell maturity through the process of neuronal differentiation in stem cells. This study explored the efficacy of dental pulp-derived induced neural cells (DPiNCs), which were cultured in dishes coated with cell-recognizing E-cadherin-Fc chimeric antibody (E-cad NCs) or N-cadherin-Fc chimeric antibody (N-cad NCs), in promoting neural regeneration in a traumatic brain injury (TBI) model. <i>In vitro</i>, DPiNCs featured axon-like projections with positive GFAP expression, weak positivity for DCX and βIII-tubulin, and positivity for MAP2 and vascular endothelial growth factor, indicating that the cell population included a mixture of mature and immature neurons. E-cad NCs exhibited staining for DCX and βIII-tubulin but reduced MAP2 staining, indicating immaturity. N-cad NCs displayed weaker DCX and βIII-tubulin staining but increased MAP2 staining, indicating maturity. In an oxygen-glucose deprivation/reoxygenation model, which simulates secondary brain injury, E-cad NC cells maintained higher βIII-tubulin and DCX expression and extended axons, denoting resistance to hypoxic stress. N-cad NCs displayed stronger MAP2 staining and axon extension, indicating resilience and maturity. <i>In vivo</i>, TBI model mice were transplanted with each cell type. Regarding motor function, the wire hang test revealed a significant improvement in the E-cad NC group with the other cell groups and sham group on day 28 post-transplantation. Additionally, in the cylinder test (right paw drags), a significant improvement was noted in the E-cad NC group compared with the DPiNC and sham groups from day 14 to day 28 post-transplantation. The E-cad NC group exhibited the highest rate of improvement on the Revised Neurobehavioral Severity Scale. Dual immunostaining on day 28 confirmed that the number of surviving transplanted cells was higher in the N-cad NC group than in the DPiNC group. Our study demonstrated the potential of cadherin-modified DPiNCs in TBI treatment, suggesting that controlling cell maturity through cadherin expression can significantly improve outcomes by promoting cell survival, integration, and neural regeneration. This study offers promising insights into regenerative medicine for acute-phase TBI, but further research is needed to clarify the long-term efficacy and the mechanisms underlying cell integration and neural network reconstruction.