Marine Creature with Severed Tissues That Won’t Die Intrigues Scientists

In studying an unusual species of sea cucumber, scientists have discovered that its tissues stayed alive for nearly three years after removal, with potential implications for regenerating their human counterparts.

An Extraordinary Sea Cucumber

Observed in the frigid waters of the Arctic and North Atlantic, the scarlet psolus (Psolus fabricii) plays a pivotal ecological role by recycling organic matter that sinks to the ocean floor. Like sea urchins and starfish, it belongs to the phylum Echinodermata, whose members are often noted for their regenerative abilities and limited cellular aging.

While researchers had assumed that tissues detached from the animal would eventually break down and die, a team noticed that weeks after detachment from P. fabricii, a fragment of its tubular foot continued to develop. Long-term experiments conducted on three specimens have recently shed light on the mechanisms at work.

«We observe growth and cellular diversification quite astonishing, literally years after the tissue was sampled», explains Rachel Sipler, lead author of the new study, published in the journal Science Advances. «We know that some lizards can regrow their tails. In this case, one wonders if the tail could regrow a new lizard.»

Potential Implications for Human Tissue Regeneration

These findings extend decades of work on so-called “immortal” cell lines, which can be cultured indefinitely in the laboratory. While, up to now, maintaining tissues alive typically required complex conditions, the tissue organization, immune activity, and development of samples taken from P. fabricii indicate that its cells have directly absorbed amino acids dissolved in seawater.

«This is probably the least ‘clean’ material we could use for experimental purposes», notes Sipler. «That environment rich in bacteria and organic matter has actually nourished the cells and allowed the tissue to heal and develop.»

According to the researchers, this extraordinary resilience echoes what is observed in organisms such as axolotls or the jellyfish Turritopsis dohrnii, and could help open new avenues for the regeneration and healing of human tissues.