Contents

26 June 2009
Vol 324, Issue 5935

About The Cover

Cover image expansion

COVER Colonies of human embryonic stem cells with differentiating cells at their edges, growing on mouse feeder cells. Cell nuclei are stained in blue, nuclear lamina in red, and cytoplasm in green (overlapping blue and red areas appear purple). The self-renewal capacity and pluripotency of human stem cells make them valuable for modeling human disease. These cells also display potential for transplantation medicine. See the special section beginning on page 1661 ). Image: Oded Kopper and Nissim Benvenisty, The Hebrew University of Jerusalem