Immunohistochemical detection of Ly6C-stained endothelium and CFSE-labeled monocytes in the brains of day 10 BDR mice. A–C, A Ly6C-positive CFSE-labeled monocyte present in the perivascular region in the brain of a day 10 BDR mouse. D–F, A Ly6C-positive CFSE-labeled monocyte that appears to be adherent to the cerebral blood vessel endothelium. G–I, A Ly6C-positive CFSE-labeled monocyte that appears to be adherent to the blood vessel (open arrow) and a Ly6C-positive CFSE-labeled monocyte that is present within the cerebral parenchyma (closed arrow). J–L, A Ly6C-immunostained CFSE-labeled monocyte that appears to be adherent to the blood vessel wall or in the process of transmigrating out of the blood vessel and into the brain parenchyma. All panels are representative of blood vessels in the periventricular region in brain sections from n = 3 day 10 BDR mice. CFSE-labeled monocytes are indicated in the panels on the left (A, D, G, J). Ly6C-immunostained cerebral endothelium and monocytes are indicated by red fluorescence in the middle panels. Combined images of Ly6C-immunostained CFSE-labeled monocytes (i.e., images from respective left and middle panels were superimposed) are demonstrated in yellow (panels on the right, C, F, I, L). Scale bar, 5 μm. BV, Blood vessel.