嗅鞘细胞促进脊髓损伤轴突再生机制的实验研究

Experimental Study on Axonal Regeneration Promoted by Olfactory Ensheathing Cells after Spinal Cord In-jury

目的探讨体外培养嗅鞘细胞的生物学特性与嗅鞘细胞促脊髓半横断大鼠轴突再生作用的关系。方法用改良的Nash法培养嗅鞘细胞,进行长时间连续观察,将鉴定后的细胞移植于成年大鼠T10脊髓左半侧横断处,在4周时取材,应用p75、NF200和GAP43免疫组化染色等方法判断轴突再生情况。结果体外细胞培养观察发现嗅鞘细胞生长由散在分布逐渐趋向集中,并具有一定的规律性。移植术后4周,p75染色显示移植的嗅鞘细胞仍然存活,主要分布在损伤区周围,且p75阳性嗅鞘细胞呈条索状分布,与GAP43阳性着色神经纤维有共同分布区域。NF200和GAP43阳性神经纤维末端向嗅鞘细胞分布区偏转,而对照组并未见上述现象。结论嗅鞘细胞这种特有的生长方式在体内、外表现一致,与该细胞促进轴突再生的作用相关。

Objective To discuss the relationship between the biological characteristics of the in vitro cultured olfactory ensheathing cells （OECs） and their effects on axonal regeneration after hemisection of spinal cord injury in rats. Methods OECs were cultured with modified Nash method and continuously observed. Obtained cells were then identified and transplanted into the area of hemisection at the T10 level in Wistar rats. Tissue sections were made 4 weeks later and staining was performed with p75, NF200, GAP43 antibody, respectively. Results The dispersive OECs became concentrated and possessed some regularity after culture. The transplanted OECs were still alive 4 weeks after operation and distributed around the damage zone. It was indicated by p75 staining that OECs and tissues had good compatibility and OECs could reduce the local cavity after injury, p75-positive OECs had strand-like distribution and occupied the same area with GAP43-positive nerve fibers. In addition, the terminus of NF200- and GAP43- positive nerve fibers turned to the OECs. However, this was not found in the control group. Conclusion The special growth pattern of OECs had same characteristics both in vivo and in vitro, which was correlated with their promotion of axonal regeneration.