GDNF基因修饰的嗅鞘细胞移植联合IN-1注射修复大鼠急性脊髓损伤

目的 研究胶质细胞源性神经营养因子(GDNF)基因修饰的嗅鞘细胞(OECs)移植联合轴突生长抑制蛋白抗体(IN-1)局部持续注射对大鼠急性横断性脊髓损伤(SCI)的修复作用.方法 构建载有GDNF基因的慢病毒(Lentivirus)载体并体外转染OECs,Western Blot检测GDNF的表达.用50只成年雌性SD大鼠建立胸脊髓全横断损伤模型,随机分为A(对照组)、B(IN-1微泵注射组)、C(OECs组)、D(GDNF-OECs组)和E(GDNF-OECs+IN-1组)5组各10只.应用神经丝蛋白200(NF200)单抗免疫组化、生物素化的葡聚糖胺(BDA),顺行神经追踪对SCI区神经纤维再生进行形态学观察.采用BBB评分评估大鼠后肢功能恢复情况.结果 术后共有13只大鼠死亡.术后8周可观察到Hoechst标记的OECs在体内存活并在脊髓内迁移;E组和D组可见SCI区杂乱无序的再生轴突,有连续性神经纤维通过损伤区;C组可见少量无序的再生轴突,可疑连续性神经纤维通过损伤区;B组和A组脊髓残端萎缩,未见轴突再生.A、B、C、D和E组后肢功能运动平均BBB评分分别为7.70±0.24、7.89±0.15、10.50±0.25、11.43±0.23和12.81±0.40.结论 GDNF-OECs移植联合IN-1抗体注射可有效促进损伤脊髓神经轴突的存活、再生,促进损伤脊髓的修复.

The repair of acute spinal cord injury in rats by olfactory ensheathing cells graft modified by gila cell line-derived neurotrophic factor gene in combination with the injection of monoclonal antibody IN-1

Objective To research the repair effect of transplantation of glial cell line-derived neurotrophic factor (GDNF) modified olfactory ensheathing cells(OECs) combination with injecting axonal growth inhibiting protein antibody(IN-1) in vivo.Methods To construct lentivirus vector with GDNF gene and infect OECs in vitro,use the immunoblotting (Western Blot) to observe the expression of GDNF was detected through Western Blot.Fifty adult female SD rats which to establish thoracic spinal cord transection injury model were randomly divided into A (control group),B (IN-1 antibody group),C (OECs group),D (GDNF-OECs group),and E (GDNF-OECs + IN-1 group) 5 groups of each 10 rats. To observe regeneration of the impaired nerve axon by NF200 immunohistochemistry,Biotinylated dextran amine(BDA)anterograde tracing corticospinal tract. Basso,Beattie and Bresnaban (BBB)score was used to evaluating hindlimb motor function recovery.Results Add up to 13 rats died post operation.OECs labeled by hoechst still survived and migrated in spinal cord 8 weeks post operation.Lots of confused and disorderly regenerated axons which crossing the injured region of spinal cord were displayed between spinal cord stumps in GDNFOECs + IN-1 group and GDNF-OECs group;some of axons existed in OECs group,but there is no obviously continue nerve fibers crossing the injured region of spinal cord ;in contrast to IN-1 and control groups,few of regenerated axons and atrophy of spinal cord stumps were observed.The results of BBB hindlimb motor rating scale were 7.70±0.24,7.89±0.15,10.50±0.25,11.43±0.23 and 12.81±0.40 for the control group,IN-1 group,OECs group,GDNF-OECs group and the allied treatment group respectively.Conclusions The transplantation of GDNF-OECs combination with IN-1 antibody may benefit the survival and regeneration of the injured axons,and accelerate the repair of the injured spinal cord and functional recover of hindlimb locomotor in rats in a more efficient way than that with OECs or IN-1 alone.