Scientists have developed cells to produce insulin; when the cells were transplanted into mice, it stopped them developing diabetes.
Scientists have found how to transform normal human skin cells into insulin-producing pancreatic cells in a move that could eventually improve treatment for diabetes patients.
They developed cells to produce insulin in response to changes in glucose levels and, when transplanted into mice, found they successfully protected the animals from developing diabetes.
The study used advanced cellular reprogramming technology, allowing scientists to scale up pancreatic cell production and manufacture trillions of the target cells.
The experts say the accomplishment could bring diabetes patients a step closer to personalised cell therapy.
The study at the Gladstone Institutes and the University of California in San Francisco was published in Nature Communications.
Matthias Hebrok, director of the UCSF diabetes centre, said: "Our results demonstrate for the first time that human adult skin cells can be used to efficiently and rapidly generate functional pancreatic cells that behave similar to human beta cells.
The scientists used pharmaceutical and genetic molecules to reprogram skin cells into endoderm progenitor cells - early developmental cells that have already been designated to mature into one of a number of different types of organs.
After another four molecules were added, the endoderm cells divided rapidly into a trillion-fold expansion, while still keeping their identity as early organ-specific cells. These were then developed first into pancreatic precursor cells, and then into fully-functional pancreatic beta cells.
First author of the study, Saiyong Zhu, said: "This study represents the first successful creation of human insulin-producing pancreatic beta cells using a direct cellular reprogramming method.
"The final step was the most unique - and the most difficult - as molecules had not previously been identified that could take reprogrammed cells the final step to functional pancreatic cells in a dish."