But because the man-made version is partly constructed from cell-mimicking microparticles, the cells do not “amplify” once implanted in patients.

They are also designed to bypass the body’s immune system in order to wipe out the risk of implants being rejected, meaning patients do not need to find a close relative willing to be a donor.

Stem cell therapies work by repairing damaged tissue, or “endogenous repair”, by secreting proteins and genetic materials.

Bone marrow transplant is currently the most widely used form, most often performed on patients with cancers of the blood or bone marrow such as leukemia.

But researchers are also trying to develop safe and effective stem cell treatments for heart disease and neurodegenerative conditions such as Parkinson’s.

Natural stem cells are extremely fragile, however, requiring careful storage and a laborious process of of typing - matching the proteins of donor and recipient - before they can be used.