Human spermatogonial stem cells extracted from testicular tissue can be turned into insulin-secreting beta islet cells normally found in the pancreas, say scientists from Georgetown University Medical Center (GUMC).
The researchers, who presented yesterday at the American Society of Cell Biology’s 50th annual meeting in Philadelphia, took 1 gram of tissue from human testes which they retrieved from deceased human organ donors, and produced about one million stem cells in the laboratory. These cells showed many of the biological markers that characterize normal beta islet cells. The cells were then transplanted into the backs of immune deficient diabetic mice and were able to decrease glucose levels in those mice for about a week, demonstrating the cells were producing enough insulin to reduce hyperglycemia.
The study’s lead investigator, G. Ian Gallicano, Ph.D., says his strategy could provide a unique solution to treatment of individuals with type 1 diabetes (juvenile onset diabetes). Several novel therapies have been tried for these patients in the past, but each has drawbacks. Transplanting islet cells from deceased donors can result in rejection, plus few such donations are available. Researchers have also cured diabetes in mice using induced pluripotent stem (IPS) cells – adult stem cells that have been reprogrammed with other genes to behave like embryonic stem cells – but this technique can produce teratomas, or tumors, in transfected tissue, as well as problems stemming from the external genes used to create IPS cells, Gallicano says.
The research was funded in part by the American Diabetes Association, patient contributions to the GUMC Office of Advancement, support from GUMC diabetes specialist Stephen Clement, M.D., and a grant from GUMC