Genetically engineered embryonic stem cells in the lab turn on a developmental program similar to the one thyroid glands go through in the body, Francesco Antonica of the Université Libre de Bruxelles in Belgium and colleagues report online October 10 in Nature. Cells following this thyroid development program form hollow, hormone-producing spheres like those found in a normal thyroid gland.
Researchers tested the dish-grown glands by transplanting them into mice whose thyroids had been destroyed with radiation. The new organs made hormones and reversed the mice’s thyroid problems.
