中文摘要：

目的研究共培养状态下树突状细胞（dendriticcell，DC）对神经干细胞（neuralstemcell，NSC）存活的影响及其作用机制。方法体外分离、纯化sD大鼠原代DC和NSC，将二者用Transwell技术共培养，用NT-3特异性抗体中和NT-3的表达；然后采用qRT—PCR方法检测DC中神经营养素-3（neurotrophin-3，NT-3）的mRNA水平，流式细胞术检测NSC凋亡；同时用免疫荧光、Westernblot技术确定NSC表面NT-3特异性受体TrkC的表达。结果与DC单独培养组相比，共培养体系中，DC表达NT-3水平显著性增强（P〈0．05）；同时共培养能显著增加NSC存活，该效应能被NT-3特异性中和性抗体阻断；共培养能够增加NSC中NT-3特异性受体TrkC表达（P〈0．05），并上调TrkC磷酸化水平，而NT-3特异性抗体能够抑制TrkC表达和磷酸化上调（P〈0．05）。结论DC和NSC共培养能够增加DC中NT-3表达，高表达的NT-3则通过NSC膜上的TrkC受体促进NSC的存活。

英文摘要：

Objective To study the effect of dendritic cell （DC） on neural stem cell （NSC） survival when they were cocuhured in vitro. Methods Primary DC and NSC isolated and purified from SD rats were cocultured by Transwell technique in vitro. The expression of neurotrophin-3 （NT-3） mRNA in DC was determined by qRT-PCR, and the apoptotic ratio of NSC was detected with flow cytometry. In addition, the expression of NT-3 specific receptor tropomyosin receptor kinase C （TrkC） in NSC was detected with immuno flourescence and Western blotting. Results Compared with simple DC group, the expression of NT-3 significantly increased in the DC cocuhured with NSC （P 〈 0.05 ）. The survival of NSC markedly increased and the effect was selectively blocked by a NT-3 specific neutralizing antibody. In addition, the levels of expression and phos- phorylation of NT-3 specific receptor TrkC significantly increased in NSC （ P 〈 0. 05 ）, and the increase could also be inhibited by the NT-3 specific neutralizing antibody. Conclusion Cocuhure of DC and NSC upregu- lates the expression of NT-3 in DC and promotes the survival of NSC in a NT-3/TrkC-dependent manner.