Treatment of chronic thoracic spinal cord injury patients with autologous Schwann cell transplantation: An interim report on safety considerations and possible outcomes

Several experimental studies have introduced Schwann cell transplantation as a means of recovery in animal models of spinal cord injury (SCI). The reported promising results together with the availability of autologous sources for Schwann cells indicate Schwann cell transplantation as a possible treatment for SCI. To address the safety and feasibility concerns we report 1-year follow-up of four patients aged between 22 and 43 years who had stable chronic (28-80 months) spinal cord injury at mid-thoracic level and treated with autologous Schwann cell transplantation. Purified Schwann cells used for transplantation were acquired from autologous sural nerve and cultured without the use of any specific mitogenic or growth factors. The patients were evaluated by means of American Spinal Injury Association (ASIA) criteria, sphincter, sexual function and Magnetic Resonance Imaging assessments for 1 year after transplantation. None of the patients were found to have any adverse effects indicating transfer of infection, neurological deterioration or other related clinical problems. Of the four patients, only one patient with incomplete SCI showed motor and sensory improvement 1 year after transplantation with extensive and continuous rehabilitation. All the four patients experienced transient paresthesia or increased muscle spasm after transplantation. Magnetic Resonance (MR) images of the patients did not show any visible changes or pathological findings after 1 year. This preliminary report shows that autologous Schwann cell transplantation is generally safe for the selected number of SCI patients but it does not prove beneficial effects. Further safety and outcome studies are recommended.