12 February 2008
Vol 1, Issue 6

About The Cover

Cover image expansion

COVER This week's issue features a Perspective on the secretion from antigen-presenting cells (APCs) of vesicles (exosomes) that contain immunostimulatory molecules. The image depicts an APC as it produces exosomes, some of which can stimulate a bystander T cell. [Image: Christopher Bickel, AAAS]