Facilitation of central nerve regeneration by choroid plexus ependymal cells

1从大鼠4^< >脑室切除脉络膜丛，移植到同株大鼠C2水平脊髓背束。脉络膜丛室管膜细胞有脱离基底层的趋势。再生轴突沿着这些改变的室管膜细胞的表面延伸。经坐骨神经注射HRP对再生轴突的跨神经节标记显示，许多再生轴突延伸穿过病变，而少数轴突进一步延伸到病变的宿主组织中。电生理检查显示，实验组在离病灶5mm处有诱发电位，而对照组无体外观察脉络膜丛室管膜细胞对神经突延伸的影响。共培养的背根神经节神经元比在层粘连蛋白上或与星形胶质细胞单层共培养的神经元延伸更广泛。在层粘连蛋白外膜、星形胶质细胞单层和脉络膜丛室管膜细胞单层上，每个神经元的神经突总长度分别为258±14 μm、385±15 μm和565±12μm海马神经元的培养结果几乎相同，这表明脉络丛室管膜细胞对CNS和pns来源的神经元都有神经突延伸作用脉络膜丛室管膜细胞可产生NCAM、n-钙粘蛋白、层粘连蛋白等黏附分子和NT-4、GDNF、bFGF、IGF-1、IGF-2.5等营养因子。原位杂交发现，脉络膜丛室管膜细胞可表达转甲状腺素、磷酸二酯酶1α、凝胶蛋白、磷脂转移蛋白、载脂蛋白E、APT结合盒转运蛋白A8、雄激素诱导醛还原酶、Na/sulfate共转运蛋白SUT-1、和FS88.6 gfp转基因小鼠脉络膜丛室管膜细胞单层培养。将培养的室管膜细胞移植到同一品系小鼠的损伤脊髓中。1 ~ 3周后，5 ~ 7%的移植细胞分化为星形胶质细胞。提示脉络膜丛室管膜细胞在适当的环境下有可能产生神经干细胞。少

1 The choroid plexus was excised from the rat 4^<th> ventricle, and grafted into the dorsal funiculus of the spinal cord at C2 level of the same strain rat. The choroid plexus ependymal cells tended to detach from the basal laminae. Regenerating axons extended along the surface of such changed ependymal cells. The transganglionic labeling of regenerating axons by HRP injection into the sciatic nerve showed that numerous regenerating axons extended through the lesion, while a few of them elongated further into the host tissue rostal to the lesion. Electrophysiological examination demonstrated that the evoked potentials were obtained at the 5mm rostal to the lesion in the experiment group, but not in the control group.2 The effect of choroid plexus ependymal cells to the neurite extension was examined in vitro. The cocultured dorsal root ganglion neurons extended neurites more extensively than those cultured on the laminin coat, or those cocultured with the astrocyte monolayers. For exam … More ple, the total length of the all neurites per neuron was 258±14, 385±15, 565±12μm in cultures on laminin coat, on astrocyte monolayers and on choroid plexus ependymal cell monolayers, respectively.3 The almost same results were obtained with the cultures of neurons from hippocampus This shows that the choroid plexus ependymal cells have the neurite extension effect on the both CNS- and PNS-derived neurons.4 The choroid plexus ependymal cells produce adhesion molecules such as NCAM, N-cadherin and laminin, and trophic factors such as NT-4, GDNF, bFGF, IGF-1 and IGF-2.5 In situ hybridization revealed that choroid plexus ependymal cells express the genes such as transthyretin, phosphodiesterase 1α, gelsolin, phospholipid transfer protein, apolipoprotein E, APT- binding cassette transporter A8, androgen-inducible aldehyde reductase, Na/sulfate cotransporter SUT-1, and FS88.6 Choroid plexus ependymal cells from GFP-transgenic mice were cultured in monolayer. Such cultured ependymal cells were grafted into the injured spinal cord of the same strain mice. After 1-3 weeks, 5-7% of the grafted cells differentiated into the astrocytes. This suggests that choroid plexus ependymal cells have the possibility to give rise to the neural stem cells in the appropriate environment. Less