Video 1. Macrophage and neutrophil behavior at the lag phase of Mm infection.

Double transgenic Tg(mpeg1:EGFP) and Tg(lyz:DsRed2) larvae infected with Mm (red) were imaged alive every ~60 sec from 1 hpi to 12 hpi by CLSM (Nikon A1). In the top panel the dynamics of GFP-positive (green) macrophages and DsRed-positive (blue) neutrophils are shown, whereas in the bottom panels the trajectories for macrophages (left) and neutrophils (right) are indicated. The magenta and red lines represent infected macrophages and neutrophils, whereas the yellow and blue lines represent uninfected leukocytes. The infected cells remain in the tail fin, except for one of the neutrophils (red line), which undergoes reverse migration along the caudal vein. The uninfected macrophages show short trajectories in the tail fin and the neutrophils show longer tracks, of which one neutrophil (blue line) seems to be scanning a large area of the tail fin. The maximum intensity projection from 11 CLSM images (step size in z-direction, 5.56 µm) is shown at 10 frames per second. Scale bar: 100 µm.