●Escherichia coli gets the message Winzer, K. & Williams, P. Nature Medicine September (2003). This News & Views article comments on the latest results from Vanessa Sperandio's lab indicating that epinephrine (adrenaline) present in the human gut can interact with the cell–cell signalling system in enterohaemorrhagic Escherichia coli.

●Professional secrets Roy, C. R. Nature 25 September (2003) Craig Roy comments on the discovery that the Sec61 complex is delivered to the phagosome after fusion with the endoplasmic reticulum. This observation could explain how antigens derived from extracellular microbial pathogens can be presented by MHC class I as well as MHC class II.

●HIV-1 infection: fooling the gatekeeper Cullen, B. R. Nature Medicine September (2003).

News & Views article on the report that the recruitment of cyclophilin A could explain the inability of HIV-1 to infect monkeys.

●Metchnikoff and the phagocytosis theory Tauber, A. I. Nature Reviews Molecular Cell Biology November (2003).

●Dissecting HIV-1 through RNA interference Stevenson, M. Nature Reviews Immunology November (2003).

●Propagation of yeast prions Tuite, M. F. and Cox, B. S. Nature Reviews Molecular Cell Biology November (2003).

●Deadly partnerships Frank, S. A. Nature 18 September (2003) Mixed genome infections of nucleopolyhedrovirus parasitize its larval host more effectively than pure infections with full-length genomes. Here, Steven Frank comments on the biological significance of this phenomenon.

●Mosquito production mooted as fast track to malaria vaccine Butler, D. Nature 2 October (2003).

●Misleading media reporting? The MMR story Lewis, J. and Speers, T. Nature Reviews Immunology November (2003). Did the media in the UK simply report last year's controversy over the MMR vaccine, or did they contribute to it? This Science & Society article examines the relationship between the media coverage of the controversy and the public understanding of the vaccine.

●Survival perspectives from the world's most successful pathogen, Mycobacterium tuberculosis Hingley-Wilson, S. M., Sambandamurthy, V. K. & Jacobs, W. R Nature Immunology October (2003).

●Keeping the lock on smallpox Weiner, D. B. Nature Medicine September (2003). Accompanying News & Views article on the papers from Hammarlund et al. and Weltzin et al. in this issue of Nature Medicine on the smallpox vaccine.

● B cells under influence: transformation of B cells by Epstein–Barr virus Küppers, R. Nature Reviews Immunology October (2003).