Severed sea cucumber appendages don't seem to die

The team also found that the immortality of severed tissues is, to the best of our knowledge, unique to P. fabricii . The researchers conducted comparative experiments on explanted tissues from related sea cucumber species, and none showed equivalent tissue survival. Zombie cucumbers Back in 1951, doctors at Johns Hopkins Hospital in Baltimore took a sample of a malignant cervical tumor from Henrietta Lacks, a 31-year-old mother of five. When they cultured these cells later, they noticed that they doubled every 24 hours in a seemingly never-ending cycle. The HeLa cells, named after the patient, were the first instance of cell immortality ever discovered in humans. “This revolutionized cell biology and a lot of medical research,” Jobson says. HeLa, though, was just a single cell type. LiPfe offers a new experimental model that enables scientists to work with a structured piece of animal tissue that maintains its own immune activity, cell cycling, and nutrient intake, without ethical concerns that come with experimenting on live animals. “On the evolutionary tree, sea cucumbers are relatively close to mammals, and they have been previously noted as having potential for interdisciplinary research,” Jobson said. The authors of the study also point out that finding naturally immortal complex tissues challenges our conventional perceptions of what being alive really means. …