The Study On Human Neural Precursor Cells Transplantation Combined With Collagen Biomaterials For The Treatment Of Rat Spinal Cord Injury Models

Spinal cord injury(SCI) is one of the medical problems to be resolved worldwide. In the present, the conventional therapy is a decompressive laminectomy surgery immediately after SCI to prevent further spinal neuronal damages. In addition, post SCI medical treatments and healthcare bring a huge economic burden to the family and our society.Theoretically, replacement treatment for the injured spinal cells using differentiated cells derived from stem cells is supposed to completely cure SCI. Considering their degradable and low immunogenic characteristics, biomaterials can be served as ideal scaffolds for transplanted cells to provide good carriers of cell growth and differentiation. Stem cell therapy combined with biomaterials can help transplanted cells survive the hypoxia-ischemia environment, overcome the homing disability and easily diffusion, and differentiate into cells promoting functional recovery, and then produce better treatment effect.Human Embryonic Stem Cells(hESCs) were chosen as the cell source, and obtained neural precursor cells(NPCs) were obtained by monolayer cell culture and small molecule induction. Using immunofluorescent staining and flow cytometry analysis, the differentiated cells were confirmed to express NPCs specific markers. Neurotrophic factors and collagen scaffold were combined the differentiated cells, and then transplanted into left lateral T9 hemisected spinal cord of rats. Postoperative observation showed that the animal body weight decreased immediately after SCI, and then gradually recovered to normal. Rats without cell transplantation showed dramatically higher death rate, indicating NPCs transplantation could help rats survive after SCI. In behavioral testing, the results showed that the BBB score increased from 2nd week, and statistical significance was obtained from 3rd week(*p = 0.0342). At the endpoint of 15 th week experiment, there was statistical significant difference between the transplantation group and the control group(**p = 0.0024), indicating that NPCs could promote motor function recovery after SCI. According to the results of section staining, there was obvious cavitation observed in the control spinal cords, and no vesicular structure was detected in transplantation group. The existence of human derived cells was detected in injured area.This study provides a reference for the future clinical treatment of SCI.