人脐带间充质干细胞移植对大鼠脊髓损伤神经功能恢复的评价

目的 观察人脐带间充质干细胞（human umbilical cordmesenchymal stem cell，hUCMSC）移植对大鼠脊髓损伤神经功能恢复的影响。方法 SD大鼠70只，随机分为3组：脊髓半切＋hUCMSC组（n=30）、脊髓半切＋PBS组（n=30）和假手术组（n=10）。脊髓半切＋hUCMSC组和PBS组又分为头侧注射、尾侧注射和头尾两侧注射三个亚组。移植后1、7、14、21、28d观察大鼠神经功能恢复情况，应用免疫组化检测移植到脊髓的hUCMSC胶质纤维酸性蛋白（GFAP）和神经元特异性烯醇化酶（NSE）表达情况。结果 大鼠脊髓半切损害后，hUCMSC组动物较PBS组有明显的神经功能恢复。植入后28d在宿主脊髓中存活的hUCMSC细胞MABl281（mouse antiuman nuclei monoclonal antibody）染色阳性，免疫组化双标染色显示MABl28l阳性细胞亦分别有NSE或GFAP表达并向损伤部位迁移，hUCMSC来源的GFAP阳性细胞可见明显的树突生长。结论 hUCMSC移植到宿主损伤脊髓后可以存活、向损伤部位迁移，并向神经元样和星形胶质细胞分化，且可促进大鼠脊髓损伤后神经功能恢复。hUCMSC作为一种来源广泛的干细胞用于治疗脊髓损伤可能具有重要的价值。

Evaluation of neurological function recovery following human umbilical cord mesenchymal stem cells transplantation to injured spinal cord in rats

Objective To evaluate the efficacy on neurological functional recovery after transplantation of human umbilical cord mesenchymal stem cells ( hUCMSCs) to injuried spinal cord in adult rats. Methods Seventy adult SD rats were transplant divided into three groups: (1) left spinal cord hemisection and transplantation of hUCMSCs; (2) left spinal cord hemisection and were injection of phosphate buffered saline (PBS); (3) sham-operation. Animals in group (1) and (2) are divided respectively into three sub-groups: hUCMSCs were injected rostrally, caudally, or rostrally and caudally into the hemisection lesion. Functional outcome measurements were performed using the modified Tarlov score at 1, 7, 14, 21 and 28 days after transplantation. Spinal cord tissue was done by immunohistochemical staining to detect whether the hUCMSCs express the astrocytic marker-GFAP (glial fibriliary acidic protein) or the neuron marker-NSE (neuron specific enolase) . Results Obviously significant improvements in neurological functional outcome were recorded in rats of hUCMSCs transplantation group at each time piont. On the 28th day,transplanted hUCMSCs survived and displayed MAB1281 staining positive in the injuried spinal cord and migrated to the injuried site, NSE or GFAP was detected in some MAB1281 positive cells with double immune-staining, in which obvious dendrite growth was noted in MAB1281 -GFAP positive cells. Conclusions Transplantation of hUCMSCs following spinal cord injury may improve neurological outcome in rats. The transplanted hUCMSCs survive, migrate to the injuried site and differentiate into neurons and astrocytes. Therefore, as a unique source of stem cells, hUCMSCs may play an important role on the treatment of spinal cord injury.