Fig. 4.

In vivo uptake and accumulation of PS-presenting liposomes in cardiac macrophages after i.v. administration to rats. MI was induced in rats and 48 h later, PS-presenting liposomes entrapping iron-oxide or saline were injected through the femoral vein. Four days later, the rats were examined by MRI (A) to evaluate macrophage accumulation at the infarct. The dark areas in the coronal sections represent macrophages, which have uptaken PS-presenting liposomes containing the iron oxide. (B) Histology/immuno-histochemistry of cross-sections from hearts excised from mice treated with i.v. injections of PS-presenting liposomes containing iron oxide, 48 h after MI. Four days after liposome injection, the animals were sacrificed and hearts were fixated and sliced for histology and immuno-staining for ED1 (a marker for resident macrophages, brown color) and iron oxide (blue color). Bar = 500 μm.