静脉移植骨髓间充质干细胞在大鼠损伤脊髓中的存活与分化

The survival and differentiation of bone marrow stromal cells after spinal cord injury in rat with intravenous administration

目的:探讨脊髓损伤后静脉移植骨髓间充质干细胞(bonemarrowstromalcells,BMSCs)治疗脊髓损伤的可行性。方法:体外分离、培养、扩增、纯化、BrdU(5-溴尿嘧啶)标记10只同种异体SD大鼠的BMSCs;WD法制成同种SD大鼠完全性截瘫的脊髓损伤动物模型,制模后7d随机分为A、B、C三组,A组22只,为应用BM-SCs移植组,B组22只,作为对照组,C组16只,作为空白对照组。A组经鼠尾静脉注射BMSCs悬液(2×106个/ml)1ml,B组经鼠尾静脉注射1mlL-DMEM液,C组作为空白对照组。注射后2、3、6周用免疫组织化学检测BMSCs在损伤段脊髓的存活、分布、分化情况并作计数观察。结果:A组移植后2、3、6周BrdU阳性的BMSCs主要分布于损伤段及邻近节段脊髓内;移植后2周BrdU阳性的BMSCs约占移植细胞数的4.9%,移植后3周占4.4%,移植后6周占2.9%。移植后2周,BMSCs形态大多变为圆形或椭圆形,部分阳性标记的细胞长出神经元样突起,约12.6%表达星形胶质细胞特异性蛋白GFAP,约5.4%表达神经元特异性核蛋白(NeuN)。B、C组损伤段脊髓内未见有BrdU阳性细胞。结论:脊髓损伤后静脉移植的BMSCs能在脊髓损伤灶内停留、存活,表现出对损伤灶的趋化性,部分存活的BMSCs可向神经元和星形胶质细胞分化,可用于脊髓损伤的细胞移植治疗。

Objective：To study the survival and differentiation of bone marrow stromal cells（BMSCs） after spinal cord injury in rat with intravenous administration.nethod：BMSCs were harvested and isolated from additional 10 adult Sprague-Dawley rats and cultured,purified,expanded and labeled with bromodeoxyuridine （BrdU）.60 adult Sprague-Dawley rats subjected to weight-drop impact causing complete paraplegia were randomly divided into 3 groups 7 days after injury.22 rats in group A were administrated with 2×10^6 BMSCs cultured in lml phosphate-buffered saline via tail vein,22 rats in group B were administrated with 1ml L- DMEM via tail vein and 16 in group C were treated as sham group.The distribution of donor cells in spinal cord were analyzed using immmohistochemical staining and the differentiation of donor cells in contused spinal cord was tested by double-labeled immmonohistochemical staining.Result：Bromodeoxyuridine-reactive cells mainly located throughout the injured and the nearby region of spinal cord at 2,3,and 6 week after injection.The survival cells in injured spinal cord accounted for 4.9%,4.4% and 2.6% of the total injection cells respectively at 2,3 and 6 week after injection.12.6% bromodeoxyuridine-reactive cells expressed the astrocytic marker GAFP and 5.4% expressed the neuronal marker NeuN at 2 week after injection.Conclusion： After SCI,BMSCs with intravenous administration migrate into spinal cord,survive and exhibit site-orient differentiation which is useful in the treatment of SCI.