來自中科院動(dòng)物研究所的段恩奎等人從小鼠真皮分離和鑒定了SKPs（皮膚干細(xì)胞）,，這一研究成果公布在Cell Proliferation 雜志上,。
SKPs表達(dá)Nestin、Fibronectin,、Stat3和Oct4等干細(xì)胞標(biāo)記分子,。SKPs能在體外擴(kuò)增并穩(wěn)定維持其干細(xì)胞特性,，并能自發(fā)向神經(jīng)細(xì)胞,、平滑肌細(xì)胞和脂肪細(xì)胞分化,。本研究首次在體外利用三步法誘導(dǎo)小鼠真皮干細(xì)胞分化為三維胰島樣集落（IPCs）。在Stage 1中,，SKPs以懸浮的細(xì)胞球傳代培養(yǎng)在DMEM/F12培養(yǎng)基（含有20 ng/ml表皮生長因子,、40 ng/ml 堿性成纖維細(xì)胞生長因子、1% B27,，培養(yǎng)基葡萄糖的濃度為17.3mM）,。在Stage 2中，SKPs在DMEM/F12培養(yǎng)基（含有1 mM二丁酰環(huán)腺苷酸,、1 μM維甲酸,、1% B27 和2% FBS，培養(yǎng)基葡萄糖濃度為5mM）中培養(yǎng)2天,，SKPs從細(xì)胞球中遷移出來形成單層細(xì)胞,。在Stage 3中，細(xì)胞在DMEM/F12培養(yǎng)基（含有10 mM 煙酰胺,、10 nM I型胰島素樣生長因子,、2nM 激活素A、1% B27和2% FBS,，培養(yǎng)基葡萄糖濃度為17.3mM）的中培養(yǎng)7天,，細(xì)胞能夠形成二硫腙陽性（Dithizone positive, DTZ+）的三維胰島樣集落（IPCs）。RT-PCR和間接免疫熒光的結(jié)果表明,，IPCs共表達(dá)胰島素和C-肽,，并表達(dá)胰腺β細(xì)胞發(fā)育和功能相關(guān)的基因和轉(zhuǎn)錄因子，如Insulin 1,、Insulin 2,、Islet-1、Pdx-1,、NeuroD/beta2、Glut-2 和 Nkx6.1,，但不表達(dá)胰腺中其它的激素,，如胰高血糖素、生長激素抑制素和淀粉酶,。體外葡萄糖刺激的功能性實(shí)驗(yàn)結(jié)果表明,，IPCs受葡萄糖濃度刺激而分泌胰島素,。（生物谷Bioon.com）
生物谷推薦原始出處：
Cell Proliferation Volume 42 Issue 1 DOI:10.1111/j.1365-2184.2008.00573.x
Efficient differentiation of insulin-producing cells from skin-derived stem cells
W. Guo*, C. Miao*, S. Liu*, Z. Qiu*, J. Li* and E. Duan*
*State Key Laboratory of Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Chaoyang District, Beijing, China , and ?Graduate University of the Chinese Academy of Sciences, Shijingshan District, Beijing, China
Correspondence: E. Duan, State Key Laboratory of Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Datun Road, Chaoyang District, Beijing 100101, China. Tel.: +86 10 648 07308; Fax: +86 10 648 07186
ABSTRACT
Objectives: Type 1 diabetes mellitus, characterized by loss of pancreatic β-cells, can be ameliorated by islet transplantation, but this treatment is restricted by the scarcity of islet tissue and by allograft rejection.
Materials and Methods: We isolated and characterized skin-derived precursors (SKPs) – an abundant source of autologous cells – and developed an experimental strategy to convert them into insulin-producing cells (IPCs) in vitro within a short period of time, through extracellular factor modification and analyses of IPCs by reverse transcription–polymerase chain reaction, immunocytochemistry and enzyme-linked immunosorbent assay.
Results: SKPs could self-assemble to form three-dimensional islet cell-like clusters (dithizone-positive) and co-express insulin and C-peptide. In addition, they expressed multiple genes related to pancreatic β-cell development and function (e.g. insulin 1, insulin 2, islet-1, Pdx-1, NeuroD/beta2, glut-2 and Nkx6.1), but not other pancreas-specific hormones and enzymes (e.g. glucagon, somatostatin and amylase). Moreover, when stimulated with glucose, these cells synthesized and secreted insulin in a glucose-regulated manner.
Conclusions: The findings of this study indicate that SKPs can differentiate into functional IPCs and can provide an abundant source of autologous cells for transplantation. This study also provides strategies to derive autologous islet-replacement tissues from human skin stem cells.
