Olfactory ensheathing cells transplanted in lesioned spinal cord prevent loss of spinal cord parenchyma and promote functional recovery

We studied the effects of olfactory ensheathing cells (OECs) transplanted in a photochemical spinal cord injury in adult rats. After dorsal laminectomy at T8 vertebra, subjacent spinal cord was bathed with rose Bengal for 10 min and illuminated with visible light by means of an optic fiber connected to a halogen lamp for 2.5 min at maximal intensity of 8 kLux. Eight injured rats received a suspension of OECs in DMEM, and another eight rats received DMEM alone. Locomotor ability scored by the BBB scale, pain sensibility by the plantar algesimetry test, and motor- and somatosensory-evoked potentials by electrophysiological techniques were evaluated for 3 months postsurgery. Finally, all rats were perfused with paraformaldehyde and transverse sections from the spinal cord segment at the lesion site were immunostained against GFAP. Area of the preserved spinal cord parenchyma was measured from the GFAP-immunolabeled cord sections. The BBB score and the amplitude of motor- and somatosensory-evoked potentials were higher in OECs-transplanted rats than in DMEM-injected animals throughout follow-up, whereas the withdrawal response to heat noxious stimulus was lower in OEC- than in DMEM-injected rats. The area of preserved spinal cord was significantly larger in OECs-transplanted rats than in DMEM-injected animals. These results indicate that OECs promote functional and morphological preservation of the spinal cord after photochemical injury.