Two Big Stem-Cell Surprises

"These results indicate that differentiated cells have more plasticity than expected, at least in mice and fruit flies: ?-cells can reproduce themselves as if they were stem cells, and spermatogonia can revert to stem cells. The authors argue that it is plausible, although unproven, that the same is true in humans. Results from the first study indicate that adult stem cells are unlikely to be an answer for treating diabetes, but finding chemical triggers that stimulate existing ?-cells to divide might be useful therapeutically. The second study suggests a future therapy for male-factor infertility and, more broadly, suggests that differentiated adult cells could be used to recreate and propagate stem cells."