嗅神经切断术后白血病抑制因子在嗅上皮中的表达

目的分析白血病抑制因子(leukemiainhibi-toryfactor,LIF)与嗅感觉神经元(olfactoryreceptorneurons,ORNs)再生的关系。方法建立嗅神经切断的小鼠动物模型,在术后8小时、2天、3天和5天分别通过免疫组化和相对半定量RT-PCR的方法,在蛋白和mRNA水平观察LIF及其特异性受体LIF-R在嗅上皮中的表达情况。结果LIF和LIF-R的表达都是在术后8小时迅速、一过性地上升,随后又迅速恢复至对照组水平。LIF由残留的ORNs表达,LIF-R则由基底细胞和嗅鞘细胞(olfactoryensheathingcells,OECs)表达。结论LIF是在ORNs凋亡再生机制中较早表达的一种细胞因子,凋亡中的ORNs产生并分泌的LIF作用于基底细胞和嗅鞘细胞,从而启动调节ORNs再生的一系列分子机制。

Expression of leukemia inhibitory factor in olfactory epithelium after olfactory nerve transection

OBJECTIVE To analyze the relation-ship between LIF (leukemia inhibitory factor)and theneurogenesis of ORNs(olfactory receptor neurons).METHODS Olfactory nerve transection was performedon mice. At 8h, 2d, 3d and 5d after the surgery, relativesemi-quantitative RT-PCR and immunohistochemistrymethods were used to demonstrate the expression ofLIF and LIF-R in olfactory epithelium. RESULTS LIFand LIF-R were upregulated and reached peak levelstransiently at 8h after operation. LIF was expressedin the injured but surviving ORNs, while LIF-R waslocalized in basal cells and OECs(olfactory ensheath-ing cells). CONCLUSION LIF is an early-onset cytokinein injury induced ORNs apoptosis and neurogenesis.After produced and excreted by ORNs, LIF functionsthrough OECs and basal cells and stimulates the pro-liferation of progenitor cells leading to neurogenesis andregeneration.