Basics of Self-Regeneration

Abstract

Regeneration is a fascinating phenomenon spanning several levels of complexity, allowing organisms to repair, renew, and reconstitute missing or damaged parts. Despite significant efforts to understand regeneration, the lack of adequate technology has slowed advances in the field until very recently. Since the beginning of the eighteenth century, scientists have looked toward animal models while striving to dissect the cellular and molecular pathways that drive regeneration. Although we are still far from the day that humans could regenerate an appendage, several mechanisms used by other animal species have been uncovered. This knowledge brings us closer to their potential transfer to humans, enabling the repair of specific tissues.

Even though regeneration occurs in many organisms, the extent of this trait varies enormously: planarian worms can regenerate their whole body and are even able to create two new worms from a bisected individual, whereas mammals can only regenerate specific parts of an organ or tissue, such as the very distal tip of a digit. Among vertebrates, however, salamanders are able to regenerate complex structures such limbs or tails, making them the object of intense scientific research. This chapter addresses limb regeneration using one specific species of salamander – the axolotl – as an example of a complex structure that is re-formed from cells of different embryonic origins. It also discusses the advances in technology that allow the pursuit and answering of important questions within this topic, and includes a brief look into the future and what remains to be explored in the field.