Direct Microscopic Observation of Human Neutrophil-Staphylococcus aureus Interaction Suggests a Potential Mechanism for Initiation of Biofilm Infection on an Implanted Medical Device.

The ability of human neutrophils to clear newly attached bacteria from a serum-coated glass surface was examined using time-lapse confocal scanning laser microscopy. Quantitative image analysis was used to measure the temporal change in bacterial biomass, neutrophil motility, and fraction of the surface area policed by neutrophils. In control experiments in which the surface was inoculated with bacteria but no neutrophils were added, prolific bacterial growth was observed.