Figure 7.

Host macrophages and iron-positive cells. To determine whether host macrophages phagocytose some iron-positive cells or released SPIO nanoparticles from labeled human cells, consecutive sections were stained with anti-mouse F4/80 antibody (specific for mouse macrophages), photomicrographed, and stained for iron. Consecutive sections were also used as negative control where primary antibody was omitted, but all other procedures were identical. Multiple localized F4/80-positive cells (brown cells) are seen (A), which show no iron on Prussian blue staining (B). Images from negative control section show no brown cells (C, D). Scale bars = 50 μm.