據(jù)英國(guó)《每日電訊報(bào)》5月12日（北京時(shí)間）報(bào)道,，美國(guó)科學(xué)家首次使用由成人的皮膚及血液中提取的干細(xì)胞培育出成熟的肝臟細(xì)胞,，并用其來(lái)治療罹患肝硬化的老鼠，結(jié)果顯示,，這些細(xì)胞的表現(xiàn)可媲美正常的肝臟細(xì)胞,。科學(xué)家表示,，未來(lái),，肝病患者有望利用自身皮膚或血液中提取出的干細(xì)胞進(jìn)行治療，不需苦苦等待他人的肝臟來(lái)進(jìn)行移植手術(shù),。
約翰霍普金斯凱末爾癌癥中心姜云陽(yáng)（音譯）領(lǐng)導(dǎo)的科研團(tuán)隊(duì)在《科學(xué)—轉(zhuǎn)化醫(yī)學(xué)》雜志上報(bào)告稱,，他們找到了一種方法，可以將皮膚,、血液細(xì)胞逆轉(zhuǎn)到其原初的干細(xì)胞狀態(tài),，再將其培育成肝臟細(xì)胞。這種方法可廉價(jià)地制造出數(shù)百萬(wàn)個(gè)肝臟細(xì)胞,，將得到的肝臟細(xì)胞注入老鼠受損的肝臟中,，可幫助肝臟再生且沒有任何副作用。
科學(xué)家指出,，盡管肝臟能在體內(nèi)再生,，但諸如肝硬化和癌癥所造成的終末期肝衰竭最終會(huì)破壞肝臟的再生能力。現(xiàn)在,，這些病人面臨的唯一選擇是接受肝臟器官或肝臟細(xì)胞移植,，但因?yàn)榫栀?zèng)的肝臟器官很少，因此,，很多人只能“忘肝興嘆”,。
干細(xì)胞是最基本的細(xì)胞形式，其能轉(zhuǎn)化為任何形式的細(xì)胞,。使用從皮膚或血液中提取出的干細(xì)胞,，也就是我們所說(shuō)的誘導(dǎo)多能干細(xì)胞(iPSC)的好處是，其非常便宜,，而且很容易在實(shí)驗(yàn)室操作,。另外,，它們?cè)从诓∪俗陨硪虼瞬粫?huì)產(chǎn)生排斥反應(yīng)。包括人體皮膚,、血液和肝臟細(xì)胞在內(nèi)的很多器官都能制造出誘導(dǎo)多能干細(xì)胞,。
在最新研究中，姜云陽(yáng)團(tuán)隊(duì)使用了肝臟細(xì)胞,、骨髓干細(xì)胞和皮膚細(xì)胞等不同的成人細(xì)胞,，將其逆轉(zhuǎn)到類似于胚胎干細(xì)胞的狀態(tài)，在這種狀態(tài)下,，誘導(dǎo)多能干細(xì)胞能發(fā)育成各種類型的細(xì)胞,。接著，科學(xué)家通過(guò)化學(xué)方法誘導(dǎo)這些多功能干細(xì)胞首先分化為不成熟的肝臟細(xì)胞,，然后將其培育成成熟的肝臟細(xì)胞,。
隨后，科學(xué)家將200萬(wàn)個(gè)用這種方法產(chǎn)生的肝臟細(xì)胞和正常的人體肝臟細(xì)胞分別注入罹患肝硬化老鼠的肝臟內(nèi),。結(jié)果發(fā)現(xiàn),，誘導(dǎo)多能干細(xì)胞產(chǎn)生的肝臟細(xì)胞移植入老鼠肝臟的成功率為8%到11%，同人體肝臟細(xì)胞11%的成功率相當(dāng),。誘導(dǎo)多能干細(xì)胞產(chǎn)生的肝臟細(xì)胞在移植后的表現(xiàn)也同正常肝臟細(xì)胞一樣好,。
科學(xué)家一直擔(dān)心，胚胎干細(xì)胞或誘導(dǎo)多能干細(xì)胞產(chǎn)生的肝臟細(xì)胞移植可能會(huì)誘發(fā)腫瘤,，但在7個(gè)月的研究階段（老鼠的7個(gè)月相當(dāng)于人類的30年）,，科學(xué)家沒有在接受移植的老鼠體內(nèi)發(fā)現(xiàn)任何腫瘤。
研究人員接下來(lái)將在人體中進(jìn)行類似實(shí)驗(yàn),。（生物谷Bioon.com）
生物谷推薦原文出處：
Science Translational Medicine DOI： 10.1126/scitranslmed.3002376
In Vivo Liver Regeneration Potential of Human Induced Pluripotent Stem Cells from Diverse Origins
Liu, Hua; Kim, Yonghak; Sharkis, Saul; Marchionni, Luigi; Jang, Yoon-Young
Human induced pluripotent stem cells (iPSCs) are a potential source of hepatocytes for liver transplantation to treat end-stageliver disease. In vitro differentiation of human iPSCs into hepatic cells has been achieved using a multistage differentiationprotocol, but whether these cells are functional and capable of engrafting and regenerating diseased liver tissue is not clear.We show that human iPSC-derived hepatic cells at various differentiation stages can engraft the liver in a mouse transplantationmodel. Using the same differentiation and transplantation protocols, we also assessed the ability of human iPSCs derived fromeach of the three developmental germ layer tissues (that is, ectoderm, mesoderm, and endoderm) to regenerate mouse liver.These iPSC lines, with similar but distinct global DNA methylation patterns, differentiated into multistage hepatic cellswith an efficiency similar to that of human embryonic stem cells. Human hepatic cells at various differentiation stages derivedfrom iPSC lines of different origins successfully repopulated the liver tissue of mice with liver cirrhosis. They also secretedhuman-specific liver proteins into mouse blood at concentrations comparable to that of proteins secreted by human primaryhepatocytes. Our results demonstrate the engraftment and liver regenerative capabilities of human iPSC-derived multistagehepatic cells in vivo and suggest that human iPSCs of distinct origins and regardless of their parental epigenetic memorycan efficiently differentiate along the hepatic lineage.
