Stem-cell paper corrected.

The article reports that the authors of a controversial paper on stem cells publish a correction of their work in this week's issue of "Nature." However, the authors stated that their overall conclusions still stand. In this context, the correction states that figures showing proteins on the surface of the multipotent adult progenitor cell contained many errors such as duplications. This paper challenged the prevailing idea that only stem cells derived from embryos were highly flexible.