Figure 2.

Representative images showing the anticorrelation between hyaluronan density and trastuzumab binding. Tissue samples were labeled with trastuzumab, OP15, and hyaluronic acid binding complex (HABC). MAb OP15 binds to an intracellular epitope on ErbB2, whereas HABC labels hyaluronan. Pixels corresponding to the membrane were identified as described in Materials and Methods. The background-corrected fluorescence intensities in the trastuzumab and OP15 images were divided by each other on a pixel-by-pixel basis, yielding the trastuzumab/ErbB2 image. The scale bar, valid for every image, is 20 µm.