The scientists were able to show that the new cells if they encountered sugar these cells sense the presence of glucose and secrete insulin in response to glucose.

However, more research is needed to make sure that the beta cells made from patient-derived stem cells don't cause tumors to develop.

Jeffrey R. Millman, PhD, an assistant professor of medicine and of biomedical engineering at Washington University School of Medicine is convinced that the stem cell-derived beta cells could be ready for human research in three to five years. At that time, Millman expects the cells would be implanted under the skin of diabetes patients in a minimally invasive surgical procedure that would allow the beta cells access to a patient's blood supply.

The research is published in the journal Nature Communications:
Millman JR, Xie C, Van Dervort A, Gürtler M, Pagliuca FW, Melton DA: Generation of stem cell-derived β-cells from patients with type 1 diabetes. Nat Commun. 2016 May 10;7:11463. doi: 10.1038/ncomms11463.

Source:
http://endo.wustl.edu/2016/stem-cells-diabetic-patients-coaxed-insulin-secreting-cells/