Figure 5.

Late progenitors differentiate into highly pure populations of astrocytes on BMP4 treatment and are capable of generating interneurons. (A): Nestin-positive late progenitors with long processes largely transform into brightly GFAP-positive cells with typical astrocyte morphology with 7 days of 10 ng/ml BMP4 treatment. Tuj1-positive bipolar neurons are present in the culture before and after BMP4 treatment. (B): The bipolar Tuj1-positive neurons in late progenitor culture stain positive for GABA and calretinin. (C): Quantification of the cellular constituents of late progenitor cultures. Nestin-positive progenitors constitute 76.9% ± 3% of the cells, and GFAP- and Tuj1-positive cells constitute 11.2% ± 2% and 12% ± 1%, respectively. With BMP4 treatment (green bars), nestin-positive percentages significantly decreased to 2.1% ± 0.3%. GFAP-positive astrocytes constituted 88% ± 0.7% of the entire culture and the Tuj1-positive neuronal population was not significantly altered (9.8% ± 0.5%). Data are mean ± SEM. Student’s t test, n = 6, ∗∗∗, p < .0001. Scale bars = 50 μm. Abbreviations: BMP4, bone morphogenetic protein 4; DAPI, 4′,6-diamidino-2-phenylindole; GFAP, glial fibrillary acidic protein.