Harvard Stem Cell Institute researchers may have found a new use for cell therapy in patients with cardiac damage.

In the latest edition of the journal Cell Stem Cell, Harvard researchers reported that specific cells in the bone marrow called c-kit+ stem cells interact with existing cardiac stem cells, stimulating them to rebuild and repair the damaged cardiac tissue.

While previous research has shown that cardiac function improves after stem cell treatment, the specific mechanism was unclear since stem cells are not believed to turn into heart tissue.

“Right now, we don’t know the best way to heal the heart in the same way that injured leg muscles heal themselves,” wrote Harvard Medical School Professor Richard T. Lee, who led the HSCI study, in an email.

“However, we have a number of clues that humans and other mammals like mice have at least a little capacity to do this.”

The study reaffirms these clues and suggests that cardiac stem cell therapy may serve to stimulate existing stem cells or progenitor cells to augment repair, holding implications for the treatment of cardiac disease and patients facing post-heart attack rehabilitation.

While stem cells have traditionally been used to replace cells, Lee’s study indicates that they may also serve as stimulators to existing cells in the body.

“In some circumstances, stimulating the body’s own stem cells at the right time might end up being simpler than growing cells in the laboratory and getting them back into the organ,” Lee wrote.

He said that his research opens the potential for drug-like treatment using stem cells.

“We might be able to stimulate the patient’s own stem cells with chemicals or drugs that are more like traditional drugs,” he wrote.

Initially tested on mice, the treatment requires further research.

“Right now, we just don’t know how to regenerate many important organs, so everything has to be on the table,” wrote Lee.

The study highlights the further possibilities regenerative medicine has to explore.

“It’s an exciting time in regenerative medicine, because the potential is so enormous and there are so many unanswered questions,” Lee wrote.

“Harvard’s a great place to tackle these challenges, because there is such a concentration of scientists interested in the problems, even though they are tough problems.”