IMAGE: EN:USER:AZUL, WIKIPEDIA
Because of their ability to differentiate into any cell type, stem cells have been thought to play an important role in limb regeneration processes. But new research has found that in zebrafishes that have lost their fins, the regrowing of the limb is carried out instead by an assortment of already differentiated cell types that are induced to proliferate. "This is evidence that we can't necessarily do regenerative medicine by plopping in generalized stem cells," said one of the researchers, Stephen L. Johnson, in a press release. "The key may be to induce the cells that are already there to grow again."