Acute transplantation of olfactory ensheathing cells or Schwann cells promotes recovery after spinal cord injury in the rat

Abstract

We compared the neurological and electrophysiological outcome, glial reactivity, and spared spinal cord connectivity promoted by acute transplantation of olfactory ensheathing cells (group OEC) or Schwann cells (group SC) after a mild injury to the rat spinal cord. Animals were subjected to a photochemical injury of 2.5 min irradiation at the T8 spinal cord segment. After lesion, a suspension containing 180,000 OECs or SCs was injected. A control group (group DM) received the vehicle alone. During 3 months postsurgery, behavioral skills were assessed with open field-BBB scale, inclined plane, and thermal algesimetry tests. Motor (MEPs) and somatosensory evoked potentials (SSEPs) were performed to evaluate the integrity of spinal cord pathways, whereas lumbar spinal reflexes were evaluated by the H reflex responses. Glial fibrillary acidic protein and proteoglycan expressions were quantified immunohistochemically at the injured spinal segments, and the preservation of corticospinal and raphespinal tracts caudal to the lesion was evaluated. Both OEC- and SC-transplanted groups showed significantly better results in all the behavioral tests than the DM group. Furthermore, the OEC group had higher MEP amplitudes and lower H responses than the other two groups. At the injury site, the area of spared parenchyma was greater in transplanted than in control injured rats. OEC-transplanted animals had reduced astrocytic reactivity and proteoglycan expression in comparison with SC-transplanted and DM rats. Taken together, these results indicate that transplantation of both OEC and SC has potential for restoration of injured spinal cords. OEC grafts showed superior ability to reduce glial reactivity and to improve functional recovery.

Lnk Deletion Reinforces the Function of Bone Marrow Progenitors in Promoting Neovascularization and Astrogliosis Following Spinal Cord Injury

“…All signals were filtered (bandpass 0.5-2,000 Hz). To ensure reproducibility, at least five replicate responses were recorded and the recording with the highest amplitude from onset to peak of the negative deflection was used for analysis [21,22]. Results were expressed as mean 6 SD.…”

Myelin-associated proteins block the migration of olfactory ensheathing cells: an in vitro study using single-cell tracking and traction force microscopy

“…The elongation of newly generated olfactory receptor axons between the peripheral and central nervous system may be largely attributed to the properties of OECs that ensheath and guide the axons of olfactory neurons that extend from the olfactory epithelium to the olfactory bulb (Doucette, 1995;Ramon-Cueto and Valverde, 1995). Given their axon growth-promoting properties, natural or genetically modified OECs have been studied extensively and transplanted into the injured spinal cord to promote axonal regeneration (Ramon-Cueto and Nieto- Sampedro, 1994;Li et al, 1997;Ramon-Cueto et al, 1998;Navarro et al, 1999;Ramon-Cueto et al, 2000;Ruitenberg et al, 2002;Garcia-Alias et al, 2004;MorenoFlores et al, 2006). Thus, OEC transplantation has emerged as a promising therapy for spinal cord injuries and for other neural diseases (Moreno-Flores and Avila, 2006;Raisman, 2007;Ramon-Cueto and Munoz-Quiles, 2010).…”

Myelination and nodal formation of regenerated peripheral nerve fibers following transplantation of acutely prepared olfactory ensheathing cells

“…Several studies have demonstrated enhanced functional recovery after OEC transplantation into the injured spinal cord (Li et al, 1998;Ramon-Cueto et al, 2000;Plant et al, 2002;Verdu et al, 2003;Sasaki et al, 2004;Garcia-Alias et al, 2005). While the precise mechanism of this functional recovery is not fully understood, several mechanisms have been suggested including remyelination (Devon and Doucette, 1992;Franklin et al, 1996;Imaizumi et al, 1998;Sasaki et al, 2004), long axon tract regeneration (Li et al, 1997;Ramon-Cueto et al, 2000;, axonal sparing (Plant et al, 2002) and plasticity associated with novel polysynaptic pathways (Keyvan-Fouladi et al, 2002;Bareyre et al, 2004).…”