About the Cover

January 15, 2015; 125 (3)

Cover image expansion

Intraaortic hematopoietic cell clusters (IAHCs) are observed in the aorta of most vertebrate species and contain the first hematopoietic stem cells generated during embryonic development. This scanning electron microscopy image shows an IAHC (yellow) tightly attached to the endothelial layer (pink) of the aorta of an E10 mouse embryo (magnification ×1600). The subaortic mesenchyme is also artificially colored (blue) to show the delimitation between the different structures. See the article by Boisset et al on page 465.