Gene-edited stem cells: the new weapon against diabetes

Stem cells were the pioneering force behind the new wave of personalized medicine of the last decade, while CRISPR and other gene-editing techniques have come to revolutionize gene therapy and the treatment of genetic diseases. It had to happen that they would eventually join forces. A new study ¹ has used gene-edited stem cells to revert diabetes in mice.

Wolfram syndrome is a recessive genetic disease caused by mutations in the WFS1 gene, one of its symptoms being diabetes. With no other solution for patients than symptomatic treatment, the researchers tested whether correcting the mutated gene in patient derived induced pluripotent stem cells (iPSCs), which would then differentiate to pancreatic β cells, the cells responsible for the production of insulin and which is impaired in patients with Wolfram syndrome and those suffering from diabetes type I.

The initial steps of the process involved isolating skin cells from the patients which were then de-differentiated to stem cells or iPSCs. These cells were then gene edited with CRISPR to have a functioning version of the WFS1 gene, and differentiated in vitro to pancreatic cells which were then injected into mice suffering from the same condition as the patients.

Within one week after treatment, blood sugar in the mice had normalized and it stayed so for the remaining six months of follow-up of the study. As incredible as the results are, there are a number of problems: for once, the number of pancreatic cells to be injected has to be pretty high, and getting to such big numbers takes time…and money; and on the other hand, it is not yet clear where would be the best place to inject the cells for maximum transplant efficiency.

Lastly, even though this gene editing works very well in case of diseases caused by a single point mutation, like Wolfram syndrome, the most typical diabetes type I and II cases are not caused by a single mutation, but many. And there, CRISPR might just not be enough. At least not yet.