科学家用实验培育出一个小肝脏。这对那些急需移植肝脏的患者来说，无疑是个好消息。
这项技术有朝一日可能用于修补不健全和受损的器官，解除等候移植的烦恼，有些病人甚至到死也没有等来供体。这个人造组织还可能用于试验新药，防止“象人”药物试验等不幸事件的发生。用同样的技术还可能培育出新的肾脏、肺和胰腺等。这项研究依然处在一个非常早期的阶段，但英国专家把它描述为“向前迈进一大步”，同时认为它对器官移植的替代选择提出“真正承诺”。
研究人员在一个盘子里用3种在人体胚胎中生成肝脏的细胞培育出一小块组织，然后把它移植到一只老鼠的大脑上。它在这里获得足够的血液供应，要至少2个月才能成长起来。这个人造组织拥有许多人类肝脏的特点，例如分解药物的能力等。实验中这个人造组织还延长了患有致命肝病的老鼠生命。这些科学家之所以选择大脑进行实验，是因为他们可把这块肝脏比较容易地固定在大脑上，同时便于进行观察。但对于人类患者来说，这些肝片事实上会用于修补肝脏。对人进行的试验最早有望在10年内进行。（生物谷Bioon.com）
生物谷推荐英文摘要：
Nature doi:10.1038/nature12271
Vascularized and functional human liver from an iPSC-derived organ bud transplant
Takanori Takebe, Keisuke Sekine,Masahiro Enomura, Hiroyuki Koike,Masaki Kimura, Takunori Ogaeri,Ran-Ran Zhang,Yasuharu Ueno,Yun-Wen Zheng, Naoto Koike,Shinsuke Aoyama, Yasuhisa Adachi & Hideki Taniguchi
A critical shortage of donor organs for treating end-stage organ failure highlights the urgent need for generating organs from human induced pluripotent stem cells (iPSCs). Despite many reports describing functional cell differentiation, no studies have succeeded in generating a three-dimensional vascularized organ such as liver. Here we show the generation of vascularized and functional human liver from human iPSCs by transplantation of liver buds created in vitro (iPSC-LBs). Specified hepatic cells (immature endodermal cells destined to track the hepatic cell fate) self-organized into three-dimensional iPSC-LBs by recapitulating organogenetic interactions between endothelial and mesenchymal cells. Immunostaining and gene-expression analyses revealed a resemblance between in vitro grown iPSC-LBs and in vivo liver buds. Human vasculatures in iPSC-LB transplants became functional by connecting to the host vessels within 48?hours. The formation of functional vasculatures stimulated the maturation of iPSC-LBs into tissue resembling the adult liver. Highly metabolic iPSC-derived tissue performed liver-specific functions such as protein production and human-specific drug metabolism without recipient liver replacement. Furthermore, mesenteric transplantation of iPSC-LBs rescued the drug-induced lethal liver failure model. To our knowledge, this is the first report demonstrating the generation of a functional human organ from pluripotent stem cells. Although efforts must ensue to translate these techniques to treatments for patients, this proof-of-concept demonstration of organ-bud transplantation provides a promising new approach to study regenerative medicine.
