據(jù)美國物理學(xué)家組織網(wǎng)11月15日報道，嗅鞘細(xì)胞（OECs）是包在嗅覺神經(jīng)纖維外面起保護(hù)作用的被膜,，過去25年來，人們一直認(rèn)為嗅鞘細(xì)胞是由鼻內(nèi)膜形成的,，但英國科學(xué)家一項新研究顯示,，嗅鞘細(xì)胞有著不同的起源。
如果將嗅鞘細(xì)胞移植到受損的脊髓中,，能促進(jìn)神經(jīng)修復(fù),，支持中樞神經(jīng)系統(tǒng)再生，這一新發(fā)現(xiàn)為治療脊髓損傷提供了更加可靠的資源,。該研究由英國維康基金和伊薩克·牛頓基金資助,，研究結(jié)果發(fā)表在本周的美國《國家科學(xué)院院刊》上。
理論上講,，可以利用病人鼻子中取出的內(nèi)膜組織,，在培養(yǎng)皿中生長出嗅鞘細(xì)胞來，然后將其移植到損傷的脊髓中就能促進(jìn)神經(jīng)修復(fù),，而無需擔(dān)心任何排異反應(yīng),。但這種方法得到的細(xì)胞數(shù)量太少，不能為治療提供足夠的來源,。
論文主要作者,、英國劍橋大學(xué)發(fā)展與神經(jīng)科學(xué)生物系的克雷爾·貝克博士說：“鼻內(nèi)膜中的嗅鞘細(xì)胞太少了，其中還包裹著周邊神經(jīng)纖維,，而這些纖維和嗅鞘細(xì)胞非常相似,，對促進(jìn)脊髓修復(fù)沒什么效果。很難從鼻內(nèi)膜中提純出足夠的嗅鞘細(xì)胞,，進(jìn)行有效的移植治療,。”
而這項新研究發(fā)現(xiàn)，嗅鞘細(xì)胞和其他包裹著神經(jīng)纖維的細(xì)胞一樣,，源自一種名為神經(jīng)嵴細(xì)胞（neural crest cells）的胚胎干細(xì)胞,。為找到嗅鞘細(xì)胞的起源，研究人員用綠色熒光蛋白標(biāo)記了胚胎神經(jīng)嵴細(xì)胞,，使其在紫外線照射下可發(fā)出綠色熒光,。利用基因技術(shù)，研究人員在小雞和小鼠的胚胎中移植了綠色熒光蛋白標(biāo)記的神經(jīng)嵴細(xì)胞,，這樣就只有神經(jīng)嵴細(xì)胞及其后代細(xì)胞能表達(dá)綠色熒光蛋白,，可以藉此追蹤神經(jīng)嵴細(xì)胞隨嗅覺神經(jīng)發(fā)育而發(fā)生的變化。通過分析胚胎切片,，這些具有分子標(biāo)記的綠色細(xì)胞包裹著一束嗅覺神經(jīng)纖維,，也就是說它們確實是嗅鞘細(xì)胞,。
而成人皮膚和毛囊中都含有神經(jīng)嵴細(xì)胞，這為在實驗室大量培養(yǎng)嗅鞘細(xì)胞提供了可能,。貝克博士說,，下一步需要研究如何把這些干細(xì)胞轉(zhuǎn)變?yōu)樾崆始?xì)胞，并研究這一過程在胚胎發(fā)育過程中是如何正常開啟的,。這可能要花幾年的時間,，但我們的發(fā)現(xiàn)為大量提純嗅鞘細(xì)胞提供新方向。（生物谷Bioon.com）
生物谷推薦英文摘要：
PNAS doi: 10.1073/pnas.1012248107
Neural crest origin of olfactory ensheathing glia
Perrine Barrauda, Anastasia A. Seferiadisa, Luke D. Tysona, Maarten F. Zwarta,1, Heather L. Szabo-Rogersb, Christiana Ruhrbergc, Karen J. Liub, and Clare V. H. Bakera,2
aDepartment of Physiology, Development and Neuroscience, University of Cambridge, Cambridge CB2 3DY, United Kingdom;
bDepartment of Craniofacial Development, King's College London, London SE1 9RT, United Kingdom; and
cUniversity College London Institute of Ophthalmology, University College London, London EC1V 9EL, United Kingdom
Olfactory ensheathing cells (OECs) are a unique class of glial cells with exceptional translational potential because of their ability to support axon regeneration in the central nervous system. Although OECs are similar in many ways to immature and nonmyelinating Schwann cells, and can myelinate large-diameter axons indistinguishably from myelination by Schwann cells, current dogma holds that OECs arise from the olfactory epithelium. Here, using fate-mapping techniques in chicken embryos and genetic lineage tracing in mice, we show that OECs in fact originate from the neural crest and hence share a common developmental heritage with Schwann cells. This explains the similarities between OECs and Schwann cells and overturns the existing dogma on the developmental origin of OECs. Because neural crest stem cells persist in adult tissue, including skin and hair follicles, our results also raise the possibility that patient-derived neural crest stem cells could in the future provide an abundant and accessible source of autologous OECs for cell transplantation therapy for the injured central nervous system.
