17 August 2010
Vol 3, Issue 135

About The Cover

Cover image expansion

Online Cover This week's issue features a pair of Research Articles (discussed in a Perspective by Morris) on roles for the amino acid and nutrient arginine in regulation of the immune response. Mieulet et al. show that sufficient dietary arginine is required for an effective innate immune response in mice, whereas Qualls et al. demonstrate that Mycobacterium tuberculosis infection of macrophages triggers the cytokine-dependent production of arginase, which degrades arginine, thus reducing the amount of nitric oxide that can be produced to fight infection. The image shows a ball-and-stick representation of arginine. [Image: Chris Bickel, AAAS]