Synergetic Effect Of Glia Cell Line-Derived Neurotrophic Factor And PC12-GFR 1-RET Engineering Cells On Spinal Cord Repair

Objective To study the Synergetic Effects of (ilia Cell Line-derived Neurotrophic Factor (GDNF) and PC12 GFR(1 RET engineering Cells on Spinal Cord Repair and investigate the signalling pathway and mechanismof GDNF.Methods First we constructed PC12-GFR(1-RET engineering cells using the technic of cell culture and cell transfeclion. Secondly, adult SD rals receiving T8 spinal cord he-misection were treated with GDNF and/or PC12-GFR(1-RET engineering cells, and the a-hilily to promote axon regeneration and prevent neuron atrophy after spinal cord injury (SCI) was investigated. Animals were hehaviorally tested for 8 weeks using the Basso. Beattie, Bresnahan locomotor rating scale and inclined plane tesl. At the end of 8 weeks, horseradish (HRP) labeled rubrospmal neurons (RSN) and corticospinal neurons (CSN) were counted and the mean soma size of RSN and CSN were quantified.Results CSN size was significantly increased in GDNF group compared with control group. Although administration of GDNF led to no significant changes in RSN mean size. there were more large neurons (more than 600um2) in GDNF group than in control group. Both of RSN and CSN mean soma size were higher in PC12-GFR(1-RET engineering cells group than in GDNF group. These results suggested thai application of exogenous GDNF and PC12-GFR ( 1-RET engineering cells could protect neurons from retrograde injury. Rals treated with PC12-GFR (1-RET engineering cells regained more improvements in hindlimb function and HRP labeled RSN and CSN number than control. GDNF could improve (he hindlimb function in early lime but have no significant increase in the function scale or in the number of HRP labeled neurons. These results suggested that application of GDNF and PC12-GFR ( 1-RET cells promote long descending system regeneration, which atl least partially mediate recovery of hindlimb function in adult rat spinal cord injury. Rats treated with GDNF + PC12 GFR (1-RET cells regained more improvements in hindlimb function than treated with GDNF or PC12-GFR( 1-RET engineering cells alone. The mean soma size, the HRP labeled RSN and CSN number was also higher in GDNF+ PC12-GFR (1-RET cells group.Conclusion Application of GDNF and PC12 GFR( 1-RET engineering cells have syn-ergetic enhancement on spinal cord repair.