In the earliest days of human development, what is it that prompts some cells to form the surface layer of skin, hair and nails and others to create the amniotic membrane that surrounds the embryo? As scientists increasingly turn to stem cell-based embryo models for their research, it is a question that has so far puzzled them. But now collaborative work between the Babraham Institute and the Wellcome-MRC Cambridge Stem Cell Institute has found the answer – and it relates to cell crowding. It should lead to the creation of more successful stem cell-based models to help us probe the black box o…
