Written by: Josephine Chen '24
Edited by: Angelina Cho '24
Humans may have the capacity to regenerate tissue. Thanks to current studies with the regenerative salamander, scientists are now better understanding the mechanisms behind organ and limb regeneration, which will possibly lead to great advances in medical therapies.
The axolotl, or Mexican salamander, is one of the most common models used to study regeneration. Unlike most salamanders which can regenerate some parts of their body, axolotls can regenerate any part of their body . When humans and other mammals have damaged tissue, a scar is formed in its place, and this prevents tissue from regenerating . However, the axolotl does not form scar tissue. The research team Godwin et al. studied the differences between the axolotl and mouse models to determine the molecular and biological properties of the axolotl that contribute to its regenerative capacity.
Macrophages are a type of specialized immune cell that removes foreign bacteria and cells at the site of injury, promoting tissue repair . These macrophages are the key to regeneration, as axolotls without an abundance of macrophages form scar tissue and are unable to regenerate . Although both axolotls and mice have macrophage signaling, axolotls have a particular signaling response from toll-like receptors (TLRs) . TLRs are the first line of defense against foreign microbes and play an important role in recognizing and stimulating an immune response against bacteria . Godwin and his team have identified important nodes in the TLR pathway of axolotls that promote regeneration .
Although complete limb regeneration in humans is not realistic currently, this research has the potential to improve regenerative medicine therapies. For instance, in diseases where tissue growth plays an important role, such as heart and lung disease, advancements in regenerative therapies would greatly enhance clinical results. Future research aims to examine how axolotl macrophages are activated to allow their tissues to repair scar-free.
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