Stem cells’ 'death-defying' quality that aids healing

Already known for their shape-shifting abilities, stem cells can now add ‘death-defying’ to their list of remarkable qualities, suggests a novel study. The new study shows how stem cells, which can contribute to creating many parts of the body, not just one organ or body part, are able to postpone their own death in order to respond to an injury that needs their attention. The study was done in planarians, which are tiny worms used as model organisms to study regeneration because of their ability to recover from any injury using stem cells.

“Planarian stem cells, even when challenged and under a lot of duress, will still respond to an injury by delaying death,” said Divya Shiroor, first author and a graduate student in Dr Carolyn Adler's lab, in the College of Veterinary Medicine.

The study, published in the journal Current Biology, is the first to demonstrate this reaction in planarians. The research team exposed planarians to radiation and then subjected half of them to injury.

Radiated worms that had not been injured experienced predicted levels of stem cell death. Stem cells of the injured worms, however, survived, gathering around the site of the wound and postponing their deaths to mount a response.

“We show that this inevitable radiation-induced cell death can be significantly delayed if animals are injured soon after radiation exposure,” said Shiroor.

This could have important implications for cancer research and therapies. “By understanding how injury prompts planarian stem cells to withstand radiation. We hope to identify genes that, if shared with mammals, could perhaps help hone existing therapies,” Shiroor said.