10 June 2015
Vol 7, Issue 291

About The Cover

Cover image expansion

ONLINE COVER Going Backpacking. One postcollege rite of passage is backpacking—Europe, Patagonia, Mount Kilimanjaro; no matter where, everything is packed properly for a seamless trip. Huang et al. engineered T cells with their own backpacks to trek to hard-to-reach tumors. T cells expressing lymph node–homing ligands were strapped to nanoparticles containing a chemotherapeutic. Upon reaching lymphoid tissues in mice, the T cells unloaded their toxic cargo, killing cancer cells. Such "pharmacytes"—depicted in various flavors on the cover—capitalize on the normal functions of cells and could be used to treat human cancers, as discussed in the Focus by Hubbell. [CREDIT: V. ALTOUNIAN/SCIENCE TRANSLATIONAL MEDICINE]