Collagen scaffold combined with human umbilical cord-derived mesenchymal stem cells promote functional recovery after scar resection in rats with chronic spinal cord injury

Effective therapeutic strategies for treating chronic spinal cord injury (SCI) are currently unavailable. Scar tissue in the lesion area is a main inhibitory factor for axonal regeneration and repair of chronic SCI. In this study, scar tissue was surgically resected from adult rats with 12week chronic SCI and then collagen scaffold (NeuroRegen Scaffold; NRS) and human umbilical cord-derived mesenchymal stem cells (hUC-MSCs) were implanted into the resected cavity to repair chronic SCI. The results demonstrated that the locomotor function of rats was not affected by surgical scar resection, indicating its safety in treating chronic SCI. Implanting NRS and hUC-MSCs promoted locomotion in rats and improved cortical motor- and somatosensory-evoked potentials. Furthermore, implanting NRS and hUC-MSCs promoted neurofilament- and -tubulin-III-positive neural regeneration and remyelination, elicited -tubulin-III-positive neuron production in the lesion area and blocked astrocyte growth outside the lesion area. In conclusion, implanting NRS in combination with hUC-MSCs provided a beneficial microenvironment for neural regeneration, showing significant therapeutic effects for chronic SCI.