New Technique Enables Safe Cell Editing

Researchers at the University of Helsinki have successfully created cells that cannot proliferate independently, and therefore can’t turn into malignant cells, a risk associated with gene-edited cells.

The new technique, published in Molecular Therapy, involves modifying stem cells to divide only when supplemented with thymidine, a crucial DNA building block. This controlled proliferation mechanism allows for efficient cell production during development while enabling growth cessation at the desired time, such as after transplantation.

"Almost all of our diseases are fundamentally caused by cellular dysfunction. One medical dream is to fight tissue damage, diseases or even aging with new healthy cells. Our study takes us a step closer to safe and novel cell therapies," explains senior author Kirmo Wartiovaara.

The research team demonstrated the efficacy of their approach by creating insulin-producing β-cells from the modified stem cells. When transplanted into laboratory animals, these cells successfully regulated blood glucose levels throughout a nearly six-month experiment.

The solution also makes it possible to edit cells without fear of adverse effects of the editing itself. For example, cells can be made into something that the recipient’s immune system does not recognize.

“Previously, such cells would have been highly risky, as the immune system also monitors the onset of cancer. Now, that risk is very small or non-existent. Ideally, these cells could be turned into products suited to everyone and, when necessary, quickly deployed,” Wartiovaara says.