Genetically modified skin grafts have protected mice from developing diabetes, suggesting the technique may help people with the condition.
The method makes use of the gene that encodes a hormone called glucagon-like peptide-1 (GLP-1). This hormone decreases appetite and helps regulate blood sugar levels by triggering the release of insulin, which removes excess glucose from the blood.
However, the hormone only works for a short period. To tackle this, Xiaoyang Wu at the University of Chicago, Illinois, and his colleagues used CRISPR gene-editing to alter the GLP-1 gene so it would make a hormone that is active in the blood for longer. They then inserted this gene into mouse skin cells in a dish, and developed them into skin grafts that could be transplanted onto mice, letting the modified hormone get into their blood.
The grafts were given to mice that were fed a high-fat diet. These mice went on to gain around half as much weight as those not given grafts, and developed less resistance to insulin. High insulin resistance is a common precursor to type 2 diabetes.
The researchers gained similar results when they made the grafts out of human skin and transplanted them onto hairless mice.