干細胞研究代表著醫(yī)學(xué)研究的巨大進步,。為避開倫理和法則的科學(xué)爭議,，部分科研人員已轉(zhuǎn)向來自于個體本身的成人干細胞研究。成人干細胞現(xiàn)在可以來自各種組織——皮膚,、骨骼甚至智齒,。以色列特拉維夫大學(xué)和加利福尼亞Scripps研究所集中于此項研究，近來他們報道了一項新突破——關(guān)于識別人類組織多能性干細胞的分類系統(tǒng),，發(fā)表在《自然》（Nature）上,。
多能性干細胞能夠分化為人體發(fā)育過程中各種細胞類型，在退行性疾病藥物開發(fā)及治療中有很大潛力。一直以來,，科學(xué)人員對于將皮膚細胞或其他身體細胞轉(zhuǎn)化為干細胞,，以生成新的大腦神經(jīng)細胞很有興趣。特拉維夫大學(xué)研究人員認(rèn)為利用自身的干細胞既是倫理可以接受的,，而且想特定情形下相對于胚胎干細胞能更好生成新組織,。
特拉維夫大學(xué)研究人員編寫新的生物信息學(xué)算法，分析數(shù)據(jù),，將各分割的內(nèi)容相互聯(lián)系起來,，有效地描述了不同的干細胞類型及特征。在此之前,，如何區(qū)分干細胞類型一直是困擾科學(xué)家的問題,。研究人員Ulitzky解釋稱，干細胞之間有細微但又顯著的差異,，了解這種屬性對開展研究有很大作用,。Ulitzky實驗室根據(jù)干細胞不同機制開發(fā)了干細胞分類的新方法。
隨著干細胞領(lǐng)域的快速發(fā)展——包括在各種細胞中（如人類皮膚細胞）誘導(dǎo)多功能化的方法——如何定義多功能越來越重要,。尤其對于人類細胞系來說,，因為無論倫理還是科學(xué)因素是不能和其他物種同等對待的。
Scripps研究所Mueller博士表示,，目前還沒有倫理上可以接受的證明人類細胞的多功能性試驗,，盡管有些干細胞被認(rèn)為是多功能的，但實際上沒有進行實踐試驗,。用150 人的干細胞當(dāng)作樣本,，研究者建立了全基因表達譜數(shù)據(jù)庫，發(fā)現(xiàn)所有的多能性干細胞系都具有明顯的相似性,，但其他細胞類型就有所不同,。分析表明，一種蛋白—蛋白網(wǎng)絡(luò)與細胞多能性相關(guān),，指出這可能是使細胞分化為多能細胞類型的一個關(guān)鍵因素,。此外，研究者計劃繼續(xù)研究此蛋白網(wǎng)絡(luò)的功能,，并開展人類基因治療,。（生物谷Bioon.com）
生物谷推薦原始出處：
Nature，455, 401-405,，F(xiàn)ranz-Josef Müller,，Jeanne F. Loring
Regulatory networks define phenotypic classes of human stem cell lines
Franz-Josef Müller, Louise C. Laurent, Dennis Kostka, Igor Ulitsky, Roy Williams, Christina Lu, In-Hyun Parl, Mahendra S. Rao, Ron Shamir, Philip H. Schwartz, Nils O. Schmidt & Jeanne F. Loring
Stem cells are defined as self-renewing cell populations that can differentiate into multiple distinct cell types. However, hundreds of different human cell lines from embryonic, fetal and adult sources have been called stem cells, even though they range from pluripotent cells—typified by embryonic stem cells, which are capable of virtually unlimited proliferation and differentiation—to adult stem cell lines, which can generate a far more limited repertoire of differentiated cell types. The rapid increase in reports of new sources of stem cells and their anticipated value to regenerative medicine1, 2 has highlighted the need for a general, reproducible method for classification of these cells3. We report here the creation and analysis of a database of global gene expression profiles (which we call the 'stem cell matrix') that enables the classification of cultured human stem cells in the context of a wide variety of pluripotent, multipotent and differentiated cell types. Using an unsupervised clustering method4, 5 to categorize a collection of 150 cell samples, we discovered that pluripotent stem cell lines group together, whereas other cell types, including brain-derived neural stem cell lines, are very diverse. Using further bioinformatic analysis6 we uncovered a protein–protein network (PluriNet) that is shared by the pluripotent cells (embryonic stem cells, embryonal carcinomas and induced pluripotent cells). Analysis of published data showed that the PluriNet seems to be a common characteristic of pluripotent cells, including mouse embryonic stem and induced pluripotent cells and human oocytes. Our results offer a new strategy for classifying stem cells and support the idea that pluripotency and self-renewal are under tight control by specific molecular networks.
