Figure 6

Fluorescence in situ hybridization (FISH) of S. epidermidis biofilms grown on polyurethane (PU) waver treated with 0, 4 or 8 µg/ml AMP2. (A) On the left hand, the panel shows the nucleic acid stain DAPI (blue) overlaid with the Cy3-labeled Staphylococcus-specific FISH-probe STAPHY (orange) for each group. The middle and right panels show either the separate DAPI or FISH Cy3 images in black and white of the respective colored image. AMP2 treatment led to a dramatic reduction of total biofilm area and fraction of FISH positive bacteria. Note also the altered fragmented appearance of the AMP treated biofilms. Scale bar = 10 µm. Pictures of 10 random areas per group were taken and results of digital images analysis are shown. (B) Total biofilm area (stained with DAPI). (C) Area of the FISH-positive bacteria (STAPHY-probe labelled with Cy3). n = 10 pictures per group. Data are shown as median with 25 and 75 percentiles.