New York, Dec 26 (IANS) Researchers have developed a synthetic version of a cardiac stem cell that could offer therapeutic benefits comparable to those from natural stem cells and could reduce some of the risks associated with stem cell therapies.Stem cell therapies aid damaged tissue in repairing itself by secreting "paracrine factors," including proteins and genetic materials.While stem cell therapies can be effective, they are also associated with some risks of both tumour growth and immune rejection. Also, the cells themselves are very fragile, requiring careful storage and a multi-step process of typing and characterisation before they can be used."The synthetic cells operate much the same way a deactivated vaccine works," said Ke Cheng, Associate Professor at North Carolina State University in the US."Their membranes allow them to bypass the immune response, bind to cardiac tissue, release the growth factors and generate repair, but they cannot amplify by themselves. So you get the benefits of stem cell therapy without risks," Cheng explained.In this study, reported in the journal Nature Communications, the researchers created the synthetic version of a cardiac stem cell that could be used in off-the-shelf applications. When tested in vitro, it was found to promote the growth of cardiac muscle cells. The synthetic stem cells are much more durable than human stem cells, and could tolerate harsh freezing and thawing. They also do not have to be derived from the patient's own cells and the manufacturing process can be used with any type of stem cell, said the study."We are hoping that this may be a first step toward a truly off-the-shelf stem cell product that would enable people to receive beneficial stem cell therapies when they're needed, without costly delays," Cheng said.