中枢神经系统损伤如脊髓损伤的修复是现代临床医学的重要难题。神经干细胞移植治疗中枢神经损伤是一种很有希望的治疗手段。但是，无论是内源神经干细胞还是移植的外源神经干细胞在中枢神经损伤处神经分化都很少，而绝大部分分化成胶质细胞，甚至形成胶质疤痕。

嗅鞘细胞是存在于嗅球中的一类特殊的胶质细胞。近年来，嗅鞘细胞移植治疗脊髓损伤成为一大热点。虽然嗅鞘细胞在治疗脊髓损伤过程中，对于促进受损神经元的轴突再生具有一定效果，但结果并不显著。戴建武课题组最近研究发现，嗅鞘细胞能明显促进神经干细胞的增殖，但抑制神经干细胞向神经元的分化。他们发现嗅鞘细胞通过调节特定信号通路促进神经干细胞增殖同时抑制神经元分化。这将为全面评价嗅鞘细胞移植对神经再生的作用，提高脊髓损伤治疗治疗效果提供依据。相关论文已经被爱思唯尔期刊《神经科学》（NEUROSCIENCE）接受。

原始出处：

（NEUROSCIENCE），doi:10.1016/j.neuroscience.2008.02.067，J. Zhang, J. Dai

Olfactory ensheathing cells promote proliferation and inhibit neuronal differentiation of neural progenitor cells through activation of Notch signaling

J. Zhang, , B. Wang, Z. Xiao, Y. Zhao, B. Chen, J. Han, Y. Gao, W. Ding, H. Zhang and J. Dai

aKey Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, 3 Nanyitiao, Zhongguancun, Beijing 100080, China
bGraduate School, Chinese Academy of Sciences, Beijing 100080, China
cDepartment of Physiology and Pathophysiology, National Laboratory of Medical Molecular Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences and Peking Union Medical College, Tsinghua University, Beijing 100005, China
Accepted 20 February 2008.  Available online 8 March 2008.

Abstract

A population of neural progenitor cells (NPCs) has been known to exist in adult spinal cord and migrate toward the lesion regions during spinal cord injury (SCI). Although there are some positive effects of the transplanted olfactory ensheathing cells (OECs) on axonal regeneration in SCI, little is known about the effects and the underlying mechanism of these grafted OECs on NPCs. In this study, we have investigated how soluble factors derived from rat OECs regulate the proliferation and differentiation of rat NPCs. The conditioned medium from cultured OECs showed its ability to promote proliferation and inhibit neuronal differentiation of NPCs. Notch signaling was apparently involved in this process. With the addition of DAPT, which inhibited Notch signaling, the effects of OEC-conditioned medium on NPCs were blocked. We thus conclude that diffusible factors released from OECs activate the Notch signaling pathway to stimulate the proliferation and suppress neuronal differentiation of NPCs. These findings reveal the likely limitation of using OECs transplantation for SCI repair.