Nature聚焦：再生医学重大发现 无干细胞也能再生

　　

生物通报道，再生医学一直与干细胞基础研究紧密连接在一起，干细胞的多能性赋予了它挑起再生医学重任的能力，然而，再生医学领域一向新的发现证实，再生也可以无需干细胞，这个神奇的研究结果发表在《Nature》上，Cells keep a memory of their tissue origin during axolotl limb regeneration。

 

文章通讯作者是来自德国德累斯顿大学再生医学治疗中心和Max Planck研究所细胞生物与遗传学研究中心的Elly Tanaka。目前主要负责再生医学动物模型研究。

 

Elly Tanaka研究小组以蝾螈为研究模型（蝾螈是研究再生的极佳模型）。Elly Tanaka表示，以前，科学家们都认为蝾螈的再生能力来自去分化的体细胞（回复到分化前的状态）。

 

在本研究中，Elly Tanaka等人首先将GFP基因转到墨西哥蝾螈能再生的细胞内，接下来，将另一没有GFP的蝾螈进行截肢术，随后，将带有GFP基因的细胞移植到蝾螈断肢上，通过荧光可直观的观察蝾螈再生的过程。

 

这些带有GFP基因的细胞分为4种，分别是：皮肤细胞、软骨细胞、肌肉细胞和雪旺氏细胞。结果发现，皮肤细胞除了再生为皮肤细胞、结缔组织和肌腱外，其他三类细胞都各自再生为原本的细胞类型。

 

这与人们先前所想的相去甚远（老的理论认为这些细胞全部去分化，变成干细胞样的细胞再统一分化）。而这一结果表明蝾螈的成体细胞具有记忆能力，当肢体受伤时，各类细胞能迅速独立再生。

 

这些研究不仅首次证实了蝾螈再生无需干细胞，并且为再生医学注入了新的思路。

（生物通 小茜）

生物通推荐原文检索：

Cells keep a memory of their tissue origin during axolotl limb regeneration

 

Martin Kragl1,3,5,6, Dunja Knapp1,3,5, Eugen Nacu1,3, Shahryar Khattak1,3, Malcolm Maden4, Hans Henning Epperlein2 & Elly M. Tanaka1,3

 

Max Planck Institute of Molecular Cell Biology and Genetics, Pfotenhauerstrasse 108,

Institute of Anatomy, Medical Faculty, University of Technology Dresden, Fetscherstrasse 74,

Center for Regenerative Therapies, University of Technology Dresden, Tatzberg 47/49, 01307 Dresden, Germany

The Regeneration Project, McKnight Brian Institute, University of Florida, Rm 326 Bartram Hall, Gainesville, Florida 32611, USA

These authors contributed equally to this work.

Present address: Institute of Metabolic Physiology, Heinrich-Heine-Universität Düsseldorf, Universitätsstrasse 1, 40225 Düsseldorf, Germany.

 

【Abstract】

During limb regeneration adult tissue is converted into a zone of undifferentiated progenitors called the blastema that reforms the diverse tissues of the limb. Previous experiments have led to wide acceptance that limb tissues dedifferentiate to form pluripotent cells. Here we have reexamined this question using an integrated GFP transgene to track the major limb tissues during limb regeneration in the salamander Ambystoma mexicanum (the axolotl). Surprisingly, we find that each tissue produces progenitor cells with restricted potential. Therefore, the blastema is a heterogeneous collection of restricted progenitor cells. On the basis of these findings, we further demonstrate that positional identity is a cell-type-specific property of blastema cells, in which cartilage-derived blastema cells harbour positional identity but Schwann-derived cells do not. Our results show that the complex phenomenon of limb regeneration can be achieved without complete dedifferentiation to a pluripotent state, a conclusion with important implications for regenerative medicine.