Traffic of CFSE-labeled DCs in the CNS of normal rats. Bone marrow-derived DCs labeled with CFSE were injected into the CSF (A-F) or brain parenchyma (G-H) of normal rats. For the detection of green CFSE-labeled cells, brain sections were examined by fluorescence microscopy after counterstaining with DAPI for nuclei visualization (blue). Photomicrographs show representative results obtained from analyses of brains on day 3 after injections. (A-B) CFSE-labeled cells (white arrows) are detected in the germinal zone homolateral to the injection site. (C-D) CFSE-labeled cells are detected in brain cortical meninges (white dotted line indicates localization of the glia limitans; circle indicates nuclei of CFSE-labeled cells). (E-F) A CFSE-labeled cell is observed in the brain parenchyma adjacent to the third ventricle (circle indicates the nucleus of the CFSE-labeled cell). (G-H) CFSE-labeled DCs injected into the corpus callosum migrate a short distance from the injection site, along the adjacent white matter tracts. LV indicates lateral ventricle; cc, corpus callosum; V3, third ventricle. Scale bars: 100 μm (G-H), 50 μm (A-B), 30 μm (C-F).