中文摘要：

目的：探讨人骨髓间充质干细胞（MSCs）对局灶性脑缺血大鼠神经功能的影响。方法：采用密度梯度分离法、贴壁筛选法体外培养、扩增人MSCs，并用流式细胞术鉴定其免疫学表型；健康Wistar大鼠50只随机均分为正常对照组（A组）、假手术组（B组）、脑缺血/再灌注后无处理组（C组）、脑缺血/再灌注后移植无血清DMEM组（D组）、脑缺血/再灌注后移植人MSCs组（E组），每组10只。D、E两组脑缺血周边区（右侧）分别移植无血清培养基5μL和5-溴-2-脱氧尿嘧啶核苷（BrdU）标记MSCs（4×10^5.μL^-1）5μL；采用免疫组化技术检测BrdU标记的人MSCs在局灶性脑缺血大鼠体内存活情况；采用前肢不对称应用试验及姿势反射试验，观察各组大鼠术后1、3、7及28 d行为学变化。结果：成功地分离并纯化人MSCs；流式细胞术检测P3MSCs结果显示，CD44、CD29均呈阳性表达，CD34、CD45、CD31均呈阴性表达；移植的人MSCs在局灶性脑缺血大鼠缺血周边区聚集并存活。各组大鼠行为学评分随着细胞移植后时间延长均逐渐降低，移植人MSCs组大鼠行为学评分较其他组显著降低（P〈0.05），该组大鼠移植人MSCs后7 d时行为学评分低于同组内其他时间点（P〈0.01）。结论：局灶性脑缺血周边注射人MSCs显著地改善大鼠脑缺血症状，前肢不对称应用试验可更客观地评价大鼠长时间运动功能变化。

英文摘要：

Objective To explore the effect of mesenchymal stem cells （MSCs） on nervous function in rats with focal cerebral ischemia. Methods The MSCs were cultivated, purified, and proliferated in vitro by density gradient and adherence to plastic dishes method. The models of Wistar rats were prepared after middle cerebral artery occlusion （MCAO） of right lasted 90 min and reperfusion 1 h. Wistar rats were randomly divided into normal control group （A, n = 10）, sham operation group （B, n = 10）, no-handle group after cerebral ischemia/reperfusion （C, n=10）, free-serm DMEM transplantation group after cerebral ischemia/reperfusion （ D, n = 10 ）, MSCs transplantation group after cerebral ischemia/reperfusion （E, n= 10）. After identified by flow cytometry, 5μL 5-bromo-2-deoxyuridine （BrdU） labeled MSCs （4 × 10^5 ·μL^-1） and 5 μL serum-free DMEM were respectively injected intracerebraly into ischemic boundary zone of right in D and E groups. Immunohistochemical method was used to detect the expression and survival of BrdU-labeled MSCs in vivo. Nervous function behavioral tests were performed on 1st, 3th, 7th and 28th day after transplantation by forelimb use asymmetry test and postural reflex test. Results MSCs were successfully purified and proliferated in vitro. The MSCs expressed CD29, CD44, but didn＇t expressed CD34, CD45, CD31 identified by flow cytometry, transplanted MSCs survived and were localized to the ischemic boundary zone. Behavioral tests of every group were improved with time prolonged. However, MSCs transplantation group was significantly better than any other groups （P〈0.05）. And on 7th day after MSCs transplantation, nervous function was significantly improved than other time points in MSCs transplantation group （P〈0.01）. Oonclusion The intracerebral administration of MSCs into ischemic boundary zone can promote the recovery of nervous function of rats with focal cerebral ischemia. Forelimb use asymmetry test can objectively evaluate motor function for a l