Researchers at Harvard University, the Harvard Stem Cell Institute, and the MGH Center for Regenerative Medicine have found a way to create healthy stem cells from adult cells–no embryo required–using an adenovirus.

The adenovirus can make the transfer in mouse cells without permanently integrating itself. The resulting induced pluripotent stem (iPS) cells can divide indefinitely but show no trace of the virus–just a temporary infection that disappears within a short time.