EMBRYONIC stem cells from mice have been coaxed into becoming sperm. The report on the work, published this week, marks the confirmation of research revealed by Â鶹´«Ã½ (10 May, p 4).
Toshiaki Noce and colleagues at the Mitsubishi Kagaku Institute of Life Sciences in Tokyo cultured stem cells before transplanting them into the testes of mice. Within weeks the cells had turned into sperm. Noce’s team have shown the sperm can fertilise an egg, but it is unclear whether they will develop into normal embryos (Proceedings of the National Academy of Sciences, DOI: 10.1073/pnas.1932826100).
