Sagrario Ortega/Spanish National Cancer Research Center (CNIO), MadridPregnant with possibilities. Cells reprogrammed in living mice (green) can contribute to both the placenta and body tissues of a developing mouse. Cells Reprogrammed in Living Mice Researchers have discovered a surprisingly effective way to “reprogram” mature mouse cells into an embryolike state, able to become any of the body’s cell types. Their recipe: Let the transformation happen in a living animal instead of a petri dish. The finding could help scientists better understand how reprogramming works and it may one day help breed replacement tissues or organs in the lab—or in patients.In...