Fig. 2. Proliferating cells in P8 control and mutant brains express progenitor cell markers, not a mature astrocyte marker. Sections from P8 control and Nf1^hGFAPKO mutant brains were subjected to double-labeling immunofluorescence with anti-Ki67 (red) and anti-nestin (green) (A,B), with anti-BrdU (red) and anti-BLBP (green) (C,D), and with anti-BrdU (red) and anti-GFAP (green) (E,F). BrdU staining in the external granule cells in the P8 cerebella serves an internal positive control for this study (E,F). (G,H) Higher magnification of sections in E,F, showing that only a small number of BrdU-positive cells in the mutant brain but not in the control brain expressed GFAP (arrows in H). (A-D) Sections from the thalamus. (E-F) Sections from the brainstem. IV, the fourth ventricle. Scale bars: 100 µm.