龟板对植入大鼠损伤脊髓内骨髓间充质干细胞分化为神经元的影响

应用密度梯度法分离大鼠骨髓间充质干细胞(mesenchymalstem cells,MSCs)进行培养,经5溴脱氧尿嘧啶(BrdU)标记和CD44(celldifferentiation protein44)染色及BrdU/CD44双标染色鉴定,将标记有BrdU的MSCs分别植入脊髓损伤体内和龟板治疗脊髓损伤体内。于移植后1周、2周、3周、4周和6周取损伤脊髓组织,对BrdU、神经丝蛋白(NF)、胶质纤维酸性蛋白(GFAP)进行免疫组化染色及BrdU/NF和BrdU/GFAP双标染色检测移植后MSCs的存活和分化。结果发现:移植后1周,两组在移植区内都可见BrdU单位、BrdU/NF双标细胞,移植后2周达到高峰。龟板组可使BrdU单位和BrdU/NF双标细胞持续高表达至移植后6周,而脊髓损伤组BrdU单位和BrdU/NF双标细胞表达减少至移植后4周,组间比较差别有显著性。结果提示益肾龟板能促进脊髓损伤移植MSCs存活和分化为神经元。

EFFECTS OF PLASTRUM TESTUDINIS ON DIFFERENTLATION OF TRANSPLANTED MESENCHYMAL STEM CELLS INTO NEURONS IN THE INJURED SPINAL CORD OF RAT

The rat mesenchymal stem cells (MSCs) dissociated from the bone marrow by density gradient method were cultured and identified by bromodeoxyuridine (BrdU) labeling or CD44 staining, and by CD44/BrdU double labeling. After then, MSCs labeled by BrdU were transplanted into the injured spinal cord and the injured spinal cord treated by plastrum testudinis, respectively. Coronal and horizontal sections of the spinal cord were cut at 1 w,2 w,3 w,4 w and 6 w after transplantation, respectively. Sections were then immunostained for BrdU, neurofilament protein (NF) or glial fibrillary acidic protein (GFAP), and for double labeling of BrdU/NF、BrdU/ GFAP to observe the survival and differentiation of MSCs. It was found that the BrdU positive cells, BrdU/NF double labeled cells in both groups were detected in the graft region one week after transplantation, and these cells peaked at 2 weeks after transplantation. BrdU and BrdU/NF double labeled cells in the group treated by plastrum testudinis remained a high level till 6 week post-transplantation; whereas the counterparts in injured group decreased till 4 week post-transplantation, there was significant difference between the two groups at each time point (P<0.05). The above results suggest that plastrum testudinis can promote survival and differentiation of MSCs into neurons in injured rat spinal cord.