Transplantation de cellules gliales olfactives après traumatisme médullaire

Guiding migration of transplanted glial progenitor cells in the injured spinal cord

Transplantation of glial-restricted progenitors (GRPs) is a promising strategy for generating a supportive environment for axon growth in the injured spinal cord. Here we explored the possibility of producing a migratory stream of GRPs via directional cues to create a supportive pathway for axon regeneration. We found that the axon growth inhibitor chondroitin sulfate proteoglycan (CSPG) strongly inhibited the adhesion and migration of GRPs, an effect that could be modulated by the adhesion molecule laminin. Digesting glycosaminoglycan side chains of CSPG with chondroitinase improved GRP migration on stripes of CSPG printed on cover glass, although GRPs were still responsive to the remaining repulsive signals of CSPG. Of all factors tested, the basic fibroblast growth factor (bFGF) had the most significant effect in promoting the migration of cultured GRPs. When GRPs were transplanted into either normal spinal cord of adult rats or the injury site in a dorsal column hemisection model of spinal cord injury, a population of transplanted cells migrated toward the region that was injected with the lentivirus expressing chondroitinase or bFGF. These findings suggest that removing CSPG-mediated inhibition, in combination with guidance by attractive factors, can be a promising strategy to produce a migratory stream of supportive GRPs.

Autologous Olfactory Lamina Propria Transplantation for Chronic Spinal Cord Injury: Three-Year Follow-Up Outcomes From a Prospective Double-Blinded Clinical Trial

We did a clinical trial to determine whether olfactory mucosa lamina propria (OLP) transplants promote regeneration and functional recovery in chronic human spinal cord injury (SCI). The trial randomized 12 subjects to OLP transplants (n = 8) or control sham surgery (n = 4). The subjects received magnetic resonance imaging (MRI), electromyography (EMG), urodynamic study (UDS), American Spinal Injury Association impairment scale (AIS), and other functional assessments. OLP-transplanted subjects recovered more motor, sensory, and bladder function compared to sham-operated subjects. At 3 years after OLP transplant, one patient improved from AIS A to C and another recovered from AIS A to B, two recovered more than three segmental sensory levels, two had less spasticity, two had altered H-reflexes and SSEP, two regained bladder and anorectal sensation and had improved bladder compliance on UDS. OLP-treated patients had partial or complete tissue bridges at the injury site compared to cavitary gaps in sham-operated patients. The limited recovery suggests that OLP transplants alone do not have significant benefits but may provide a rationale for larger randomized trials or combination therapies.

Strategies for spinal cord repair after injury: a review of the literature and information

INTRODUCTION

Thanks to the Internet, we can now have access to more information about spinal cord repair. Spinal cord injured (SCI) patients request more information and hospitals offer specific spinal cord repair medical consultations.

OBJECTIVE

Provide practical and relevant elements to physicians and other healthcare professionals involved in the care of SCI patients in order to provide adequate answers to their questions.

METHOD

Our literature review was based on English and French publications indexed in PubMed and the main Internet websites dedicated to spinal cord repair.

RESULTS

A wide array of research possibilities including notions of anatomy, physiology, biology, anatomopathology and spinal cord imaging is available for the global care of the SCI patient. Prevention and repair strategies (regeneration, transplant, stem cells, gene therapy, biomaterials, using sublesional uninjured spinal tissue, electrical stimulation, brain/computer interface, etc.) for the injured spinal cord are under development. It is necessary to detail the studies conducted and define the limits of these new strategies and benchmark them to the realistic medical and rehabilitation care available to these patients.

CONCLUSION

Research is quickly progressing and clinical trials will be developed in the near future. They will have to answer to strict methodological and ethical guidelines. They will first be designed for a small number of patients. The results will probably be fragmented and progress will be made through different successive steps.