Figure 3.

WAVE1 defect causes delayed oligodendrocyte differentiation. Mixed CNS cells from P0 WT and WAVE−/− mice brain were dissociated in DMEM and cultured for 15 d with changing medium every 3 d. A, Neurofilament (NF), glial fibrillary acidic protein (GFAP), and O4 were stained for different populations of CNS cells. Oligodendrocytes were double labeled with O4/Olig2 (B) or O1/Olig2 (C). Significant defects in process formation were seen in WAVE−/− O4+ cells compared with WT controls. D, Total cell number by DAPI+ and total oligodendrocyte number by Olig2+ were counted in square millimeters. Cell numbers counted WT versus WAVE−/− was not statistically significant. E, However, the number of O4+/Olig2+ and O1+/Olig2+ double-stained cells was significantly reduced. In addition, mature O1+ oligodendrocytes with membrane sheets were dramatically reduced (72%) compared with wild-type control (F). The data shown here are representative of four independent experiments. Error bars indicate SEM. ∗p < 0.05 and ∗∗p < 0.005 by ANOVA (n = 4). Scale bars: A, 20 μm; B, 5 μm; C, 10 μm.