Advance could help grow stem cells more safely

The most productive way scientists have devised to nurture colonies of human embryonic stem cells is to do so atop a bed of mouse cells. That may be fine for lab research, but it poses an unacceptable contamination risk for stem cells intended for transplant into human patients. In a new study, Brown University bioengineers have developed a synthetic bed that works about as well as the mouse cells, called fibroblasts, without any possibility of contamination.