Figure 6.

Cultured Id2^−/− neural progenitors exhibit altered growth kinetics and premature astroglial differentiation. SVZ cells were explanted from neonatal mice and examined for alterations in growth kinetics in vitro. A, Neurospheres were dispersed and cells were plated at an initial density of 20,000 cells in 24-well plates in triplicate and counted days 1–4. B, BrdU (1 mg/ml) was added to neurosphere cultures immediately after dispersion collected at 24, 48, and 72 h after addition of BrdU. Accumulation of BrdU by WT and Id2^−/− cells was analyzed using flow cytometry. Results representative of three independent experiments are shown. C, Sphere size was measured using image analysis software 48 h after dispersion. D–G, Neurospheres were dispersed and grown in proliferation conditions for 12 and 24 h at each time point, cells were dispersed and cytospin cytologic slides of 50,000 cells were immediately prepared. Cytospin preparations were analyzed using GFAP immunofluorescence and Hoechst dye counterstain (D, WT, 24 h; E, WT, 48 h; F, Id2^−/−; G, 48 h).