Differing Schwann Cells and Olfactory Ensheathing Cells Behaviors, from Interacting with Astrocyte, Produce Similar Improvements in Contused Rat Spinal Cord's Motor Function

In recent years, cell behaviors of Schwann cells (SCs) and olfactory ensheathing cells (OECs) when interacting with astrocytes was appraised qualitatively in vitro and in spinal cord injury model of dorsal crush and transection and in normal white matter. In this study, with an attempt to select a candidate for cell-mediated repair of the spinal cord injury, SCs or OECs were transplanted into contused spinal cord in adult rats. The interaction with host astrocytes was assessed at 3 and 6 weeks after transplantation under light and electron microscope. The motor function of the rat was appraised with the BBB locomotor rating scale and cortical somatosensory evoked potentials (CSEP) recording. Within SCs cord, the astrocytes underwent proliferation and hypertrophy. The myelinated axons were separated into the groups by the glial membrane. Within OECs cord, astrocytes did not undergo the proliferation and hypertrophy. The myelinated axons were not divided into groups by the scar tissue. SCs graft, compared with OECs graft, induced more enhanced glial fibrillary acidic protein (GFAP) immunoreactivity with a distinct astroglial border between the normal and injured tissues. The distribution of SCs was more concentrated and less migrated than that of OECs. SCs induced weaker NF immunoreactivity and functional recovery compared to OECs, but no significant differences between the two groups was revealed by the statistical analysis. As we know, this is first time to compare behaviors of SCs and OECs in the contusion model, and the data indicates that although in vivo cell behaviors of SCs and OECs are different in interacting with astrocyte, both cell types can improve the motor function of the contused rats.