This month's winning image was submitted by Paul Dean (University of Bristol, UK (Paul.Dean@bristol.ac.uk)). It shows an insect blood cell engulfing bacteria.

Red fluorescence represents tetramethyl rhodamine isothiocyanate (TRITC)-conjugated-phalloidin-labelled actin in the insect blood cell. Green fluorescence represents fluorescein isothiocyanate (FITC)-labelled Escherichia coli. The image was obtained using a laser-scanning confocal microscope (LSM 510, Zeiss). Bar, 10 μm.

The winner would like to acknowledge the help of Stuart Reynolds and Keith Charnley (both at the University of Bath, UK).

We are pleased to acknowledge the help of our two external advisors, Ariel Ruiz i Altaba (Developmental Genetics Program, New York Medical Center) and Lelio Orci (Department of Morphology, University Medical Center, Geneva).