ABSTRACT
BACKGROUND:Stem cells have been widely used in the treatment of spinal cord injury,but the clinical application is limited by immune rejection,difficulty in cell harvesting and purification.However,human nasal mucosa mesenchymal stem cells (hNM-MSCs) have no such problems,and its clinical application in the treatment of spinal cord injury has been not reported yet.OBJECTIVE:To observe the biological characteristics of autologous hNM-MSCs and its clinical efficacy in the treatment of advanced incomplete spinal cord injury.METHODS:NM-MSCs were isolated from the human nasal mucosa,cultured and identified in vitro.The ultrastructure of NM-MSCs was observed by transmission electron microscope and scanning electron microscope.Then the NM-MSCs were induced to differentiate into osteocytes,adipocytes,stem cell spheres,or neurons in vitro.Totally eight patients with incomplete spinal cord injury were enrolled and subjected to hNM-MSCs transplantation via lumbar puncture for 1-3 sessions of about 5× 107 cells each,with an interval of 5-7 days,after the approval of the medical ethics committee.All the patients were followed up for 6 months.Preoperative and postoperative therapeutic effect evaluations were performed on the basis of American Spinal Injury Association (ASIA) scores.RESULTS AND CONCLUSION:Under light microscope,the NM-MSCs were mainly spindle-shaped,positive for STRO-1 and exhibited a radial arrangement.NM-MSCs highly expressed CD73,CD90 and CD105,but did not express CD34 and CD45,with the purity of over 97％.And lots of podgy microvilli were seen on the surface of NM-MSCs under the scanning electron microscope,and two kinds of cell morphologies were seen under the transmission electron microscope.Moreover,hNM-MSCs had the ability to differentiate into osteocytes,adipocytes,stem cell spheres and neurons.During the 6-month follow-up,seven patients achieved neurological function recovery to different extents except for one patient,and no side effects were found.It is concluded that hNM-MSCs can become the ideal seed cells for tissue-engineered cell repair.Autologous NM-MSCs transplantation for the treatment of spinal cord injury can achieve the ideal effect,with the value of clinical application.