Just rubbing a medicine on your skin could soon relieve ailments like diabetes, all thanks to newly developed patches of synthetic skin that could deliver gene therapies to patients non-invasively.
Jon Vogel and colleagues at the National Institutes of Health in Bethesda, Maryland, cultured fibroblasts and keratinocytes - the principal cells of the skin - and introduced into their genomes the gene for atrial natriuretic peptide (ANP), which is naturally released by cells in the heart.
It reduces blood pressure by dilating blood vessels and lowering blood volume.
The researchers mixed these cells into a jelly-like matrix.
The cells in the gel formed layers just like those in human skin and these delicate grafts were then attached to the backs of mice.
After a few weeks, the grafts were accepted by the mice as normal skin and had started pumping ANP into their bloodstreams.
The team used tiny radio transmitters inserted into the animals' arteries to measure blood pressure.
These showed the grafts led to a drop in blood pressure, and it stayed low even when the mice were put on a high-salt diet.
Vogel believes that synthetic skin grafts could be used to deliver genes for proteins that might otherwise be expensive or difficult to administer.
"Skin is a good target because it's accessible. If anything goes wrong you can just remove it," New Scientist quoted him as saying.
Human trials are still a few years away, said Vogel.
"We hope to test the graft on larger animals, such as pigs, which have skin similar to humans," he added.
The team are working on ways to control or boost the dose that the skin patch delivers.
"In the case of diabetes, you could imagine insulin being released at a constant rate. You could just rub in some cream to control your blood sugar levels," said Vogel.
The study has been published in Proceedings of the National Academy of Sciences.