Cover photograph (Copyright © 2007, American Society for Microbiology. All Rights Reserved.): Francisella tularensis LVS growing within human bronchial epithelial (HBE) cells 24 h after invasion into the nonphagocytic cells. The cellular F-actin was visualized with rhodamine phalloidin and is stained red, bacterial envelopes were detected with anti-Francisella rabbit polyclonal antibody as the primary antibody (stained green), and the nucleic acid of both the bacteria and the HBE cells was detected with TO-PRO-3 iodide (pseudocolored blue). The number of bacteria present in the cells at 24 h is approximately 1,000-fold higher than the number at the time of cellular entry. (See related article on page 3178.)