The key lay in finding just the right recipe of growth factors and nutrients to induce a stem cell to become a heart cell, a neuron, an insulin-making cell or something else.

Brazilian study has shown that stem cell transplants in patients with diabetes type 1 May kick start the pancreas into producing insulin again.

In the new study, however, researchers were able to take cells from men's testicular tissue, isolate stem cells, and turn them into insulin-secreting islet cells.