(A) Brain section from a CCL2 transgenic mouse that was administered 10 μg/kg PTx and immunolabeled for laminin (brown) shows that the dextrans (red fluorescence) have crossed the basal lamina of the endothelial layer. (B) Fluorescence microscopic imaging of a vessel that is leaking dextrans (red) with corresponding staining for GFAP (green) and DAPI (blue) from a CCL2 transgenic mouse that was administered 20 μg/kg PTx. Overlay shows that the dextrans have moved past the astrocytic barrier. (C) Comparable images of a non-leaking vessel shows dextrans confined to the perivascular space. Original magnification 100×.