Migration and effect of cotransplantation of olfactory ensheathing cells（OECs） and Schwann cells（SCs）on axon regeneration in injured spinal cord

English Keywords:Spinal cord injury  Olfactory ensheathing cells  Schwanne cells  Cell transplantation  Migratation  Axon regeneration

English Abstract:

  【Abstract】 Objective：To investigate varied migration and effect of cotransplantation of olfactory ensheathing cells（OECs） and Schwann cells（SCs） on axon regeneration in injured spinal cord of rats.Method：Spinal cord contusion at T10 segment was induced in adult female SD rats（n=8，75±1d） by NYU impactor at the height of 25mm，and all animals were assigned as follows：（1）GFP+OECs cotransplantation 0.5mm cephalad and caudally to the injured site combined with injection of SCs labelled by hochest at injured site；（2）Mixed OECs and SCs（1：1）transplantation 0.5mm cephalad and caudally to injured site after 2 weeks（cell density：1×105/μl，depth：1.75mm，1.5mm，1.0mm，0.5mm，dosage：0.5μl cell suspension/per depth）.The rats were sacrificed at 1th and 8th week after transplantation respectively，and the T8-11 cord containing lesion and transplantation site were dissected，sectioned and stained immunochemically for fluorescent microscopy and then analsized for cell migration and axon regeneration.Result：After cotransplantation of OECs and SCs，SCs remained largely at the transplanted site，while OECs were capable of migrating from injection site to injured site longitudinally and laterally.Most of the OECs migrated to the injured site in gray matter and white matter，and some migrated through central canal or pia from the entry site. In transplantation of OECs and SCs to same site，OECs could migrate to the injury site，and SCs could migrate in a limited distance. After combined transplantation of OECs and SCs，NF+ and GAP-43+ axons were observed migrated parallelly to the OECs processes，transplantation with SCs contained a greater concentration of NF+ axons，but no GAP-43+ axons was evidenced.NF+ axons penetrated into the SCs grafts from all directions and twisted irregularly in the injured site.After transplantation of OECs and SCs into same site，numerous NF+ and GAP-43+ axons parallel to mixed cells processes were observed with the density of NF+ axons being low in injured site.Conclusion：Both mixed and combined transplantation of OECs and SCs has the capacity for cell migration and axon regeneration in contused spinal cord of rats，while the former is better than latter due to the good growth protocol.