Did you know that salamanders are unique in the vertebrate world as they’re capable of repairing their hearts, tails, spinal cords, brain, and regrowing limbs?
This makes them an obvious candidate for regenerative research. Dr James Godwin, of the Australian Regenerative Medicine Institute at Monash University, sees the Salamander’s “perfect regeneration” as a holy grail. “We’re trying to work out what the requirements are so we can unlock that potential in
mammals,” he says.
Macrophages are a type of repairing cell that devour dead cells and pathogens, and trigger other immune cells to respond to pathogens. In humans, they’re also important to muscle repair.
Godwin and the team at ARMI removed the macrophages the Salamanders and found that the animals were no longer able to regenerate limbs. He believes that the cells release chemicals that are vital to the
Salamanders’ regenerative powers. More research is needed to establish exactly how regeneration works, and Godwin is currently conducting experiments to investigate. “This really gives us somewhere to look for what might be secreted into the wound environment that allows for regeneration,” he tells ABC News.
But why has evolution lost such a seemingly useful capacity as the ability to regrow a whole limb? Godwin says he is speculating, but formation of scars to prevent blood loss and infection may have been vital for mammals which are constantly on the move. Or we could have just been unlucky in the “evolutionary lottery” he says. “Sometimes things just get lost.”