科学也许又朝弄清附肢再生和脊髓修复迈进了一步。最近Forsyth研究所研究人员发现，为了实现再生，有些细胞必须死亡。这种发现为探索再生机制，治疗人类断肢、遗传综合症、出生缺陷、癌症、再生性疾病、衰老以及器官衰竭带来了新的参考。Forsyth人员通过研究蝌蚪（非洲爪蟾幼体），检测到了细胞再生的支柱。
非洲爪蟾蝌蚪是研究再生的理想模型，因为其能够再生出有功能的尾部，包括肌肉、脉管系统、皮肤和脊髓等。Forsyth人员研究凋亡（apoptosis）在再生中的作用。由Forsyth再生和发育生物学中心Michael Levin博士率领的研究小组，发现凋亡在发育过程中的新作用，以及在再生过程中的关键作用。研究结果将刊登于2007年1月1日《Developmental iology 》(v301i1).
研究摘要
为了弄清再生过程的机制，Forsyth人员研究再生尾芽（tail bud）中细胞数量的动态变化。先前有研究证实程序性细胞死亡是控制细胞数量的一种机制，许多发育系统（心脏、四肢和颅面模式）等都有涉及。
此次发现，尾部再生除了需要大量的组织增殖，早期的凋亡事件也是不可少的。正常的尾部再生过程包括一小部分细胞凋亡。如果在头24小时抑制细胞凋亡，再生将不能进行，神经轴突畸型生长。晚期抑制细胞凋亡没有效果。提示，特异性细胞的程序性死亡，是再生程序的非常早期的步骤。Levin小组下一步准备鉴别出必须凋亡的细胞，以寻找细胞控制再生的信号。
英文原文：
Forsyth Scientists Discover Early Key to Regeneration
Science may be one step closer to understanding how a limb can be grown or a spinal cord can be repaired. Scientists at The Forsyth Institute have discovered that some cells have to die for regeneration to occur. This research may provide insight into mechanisms necessary for therapeutic regeneration in humans, potentially addressing tissues that are lost, damaged or non- functional as a result of genetic syndromes, birth defects, cancer, degenerative diseases, accidents, aging and organ failure. Through studies of the frog (Xenopus) tadpole, the Forsyth team examined the cellular underpinnings of regeneration.
The Xenopus tadpole is an ideal model for studying regeneration because it is able to re-grow a fully functioning tail and all of its components, including muscle, vasculature, skin, and spinal cord. The Forsyth scientists studied the role that apoptosis, a process of programmed cell death in multi-cellular organisms, plays in regeneration. The research team, led by Michael Levin, Ph.D., Director of the Forsyth Center for Regenerative and Developmental Biology, found that apoptosis has a novel role in development and a critical role in regeneration. According to Dr. Levin, 揝imply put, some cells have to die for regeneration to happen.
