Corpses have long been used for organ transplants, but new research suggests that they may be able to serve as a vessel for stem cell donations as well. A study conducted by researchers at the University of Miami found that stem cells can be collected from bodies as late as five days after death.

Human bone marrow holds mesenchymal stem cells, which can be converted into just about any cell in the body, depending on the site of their injection. However, stem cell therapy requires an inordinate amount of cells, which can make the cells prohibitively difficult to obtain from a living donor. The researchers wondered if cadavers might serve as the answer. Though most cells die immediately or shortly after death, researchers hoped that mesenchymal stem cells might stay alive, because they are stored in low-oxygen portions of the body.

Gianluca D'Ippolito and his colleagues kept the finger bones of two cadavers. After five days, the team extracted MSCs and left them to grow in a Petri dish. Five weeks later, the team was able to convert the stem cells into cartilage, bone, and fat cells. A current study expanding on the first is now underway as researchers attempt to coax the MSCs into becoming nerve and intestinal cells as well.

These stem cells are also generally immune to rejection from the body, which is particularly useful in patients with graft-versus-host disease, an illness in which a bone marrow or stem cell transplant attacks the body in which it was implanted. In fact, mesenchymal stem cells appear to pacify the immune system.

D'Ippolito and his colleagues believe that the treatment could allow researchers to obtain billions of stem cells from a single source. However, other researchers are less optimistic. One expert, Paolo Macchiarini, said to New Scientist that the stem cells may not be as healthy as they seem, due to cold temperatures and exposure to surrounding cells.

Yet another notes that medical regulators believe that patients should be treated from stem cells from only one source. If a living source is used, there is a bottomless well but, if a cadaver is used, sooner or later the stem cells will run out.