Synergic effects of EPI-NCSCs and OECs on the donor cells migration, the expression of neurotrophic factors, and locomotor recovery of contused spinal cord of rats.

Cell-based therapy is a promising strategy for the repair of spinal cord injury (SCI), and the synergic effects of donor cells are emphasized in recent years. In this study, epidermal neural crest stem cells (EPI-NCSCs) and olfactory ensheathing cells (OECs) were transplanted into the contused spinal cord of rats separately or jointly at 1 week after injury. At 3 and 9 weeks posttransplantation, migration of the donor cells, expression of brain-derived neurotrophic factor (BDNF) and glial cell line-derived neurotrophic factor (GDNF) and functional recovery of the contused cord were determined by techniques of histopathology, quantitative real-time polymerase chain reaction (qPCR), immunohistochemistry and Basso-Beattie-Bresnahan (BBB) score. The results showed that the migration and distribution of EPI-NCSCs in vivo were promoted by OECs at 3 weeks after transplantation, but they vanished at 9 weeks. The expression of BDNF and GDNF was significantly increased by co-transplantation at molecular and protein level. Although the expression of both factors in EPI-NCSCs- and OECs-injected group was lower than in co-injected group, it was higher than in control groups. Similarly, the best locomotor recovery of the contused cord was acquired from co-injected animals. As we know, this is the first time to study the synergic effects of EPI-NCSCs and OECs, and the data indicates that donor cells migration, expression of neurotrophic factors (NTFs), and recovery of motor function can be improved by EPI-NCSCs and OECs synergistically.