Researchers have identified a set of molecular ‘flags’ that are present on the surface of human stem cells. Stem cells are cells that have the potential to differentiate into a variety of specialised cells. By recognising the flags, researchers can now accurately track and investigate stem cells as the cells transition between different states.

This approach has revealed new insights into the timing and coordination of the changes in gene activity and modifications to the DNA that occur as cells are reprogrammed from one state to another. These findings will open up new ways to improve the efficiency of cell reprogramming and to drive stem cells to become different types of specialised cell. These are important steps towards future applications in regenerative medicine, which would require the use of stem cells to create specialised cells, tissues or organs to maintain normal function.