Four steps for validating stem cells

Scientists at EPFL and in the US have developed a robust method for characterizing human embryonic stem cells and their potential for medical applications. The key to utilizing stem cells for regenerative medicine and tissue engineering lies in a property of theirs called pluripotency. This refers to the cells? ability to differentiate into different types of cells. This means that we need to be able to reliably obtain, culture and maintain fully pluripotent stem cells. It has been difficult to generate human embryonic stem cells at the earliest stage of pluripotency, in what is named 'ground' or 'naïve' state, whereas this is readily done with mouse cells. The labs of Rudolf Jaenisch at MIT , Joe Ecker at the Salk Institute , and Didier Trono at EPFL have now developed a four-step process for determining accurate signatures of human embryonic stem cells and relating them to precise developmental stages. The work, a first for human embryonic stem cells, is published in Cell Stem Cell .