Scientists are addressing a pioneering stem cell procedure that has potentials for treating people with damaged muscles without any risks. Researchers have for the first time fruitfully implanted "synthetic" cardiac stem cells which effectively repaired muscle tissue that had been deteriorated by a heart attack.
Traditional stem cell therapy comes with a risk of cancer because scientists are unable to stop the cells replicating and forming tumors. But because the artificial version is partly built from copying microparticles, the cells do not "amplify" once set in patients.
Stem cell therapies work by repairing damaged tissue, or "endogenous repair", by secreting proteins and genetic materials. Bone marrow transplant is now the most widely used procedure, most often done on patients with a blood cancer or in bone marrow such as leukemia.
But researchers are also working out to develop safe and effective stem cell treatments for heart disease and neurodegenerative victims such as Parkinson's. Natural stem cells are fragile, however, requiring careful storing and a laborious process of typing - matching the proteins of donor and recipient - before they can be hands-down.
Synthetic stem cells, by distinction, are easier to preserve and can be reformed for use on several parts of the body. It is also less vital that they are getting it from the patient's own cells, or a close relatively match, because it won't cause anything in the body's immune system.
"We are hoping that this may be first step towards a truly mass-produced cell product that would enable people to receive beneficial stem cell therapies when they're needed, without costly delays," said Ke Cheng, associate instructor of molecular biomedical sciences in North Carolina State University.
"They synthetic cells operate much the same way as deactivated vaccine works," said Professor Cheng. "Their membranes permit them to bypass the resistant response, bind to cardiac tissue, release growth factors and generate repair. "But they cannot amplify by themselves, so you get the benefits of stem cell therapy without the risks."
Now, donated stem cells need to meticulously match the patient's own, meaning they often come from a brother or sister. In the absence of a close relative, patients can undergo a so-called "matched unrelated giver transplant", involving stem cells alike but not matching their own.
These are more likely to aggravate a reaction, which can be dangerous when the immune cells within the contributed stem cells attack the body. This answer, a called graft versus host disease, can be controlled to an amount by anti-rejection drugs.