Fig. 5.

Appearance of oRG-like progenitors. (A–F) Percentages of apical progenitors with vertical (cleavage angle at 60–90°) and nonvertical (0–30° and 30–60°) cleavages (A and B) in the VZ of day 70 (C) and day 91 (D–F) hESC-derived cortical NE. p-Vimentin, M-phase marker. Arrowhead, pericentrin. Cells analyzed: n = 42 (day 70) and n = 33 (day 91). (G–I) Basal progenitors (Pax6⁺, Sox2⁺) and intermediate progenitors (Tbr2⁺) in the SVZ of day 91 culture. (H) Percentages of Sox2⁺/Tbr2⁻ and Sox2⁻/Tbr2⁺ progenitors within all progenitors (Sox2⁺ and/or Tbr2⁺) in the CP. The percentage of Sox2⁺/Tbr2⁻ progenitors increased from day 70 to day 91, whereas Sox2⁻/Tbr2⁺ progenitors decreased in proportion. ***P < 0.001, Student t tests between day 70 and day 91 samples. Non-VZ progenitors from four cortical NE domains from each day were counted. (I) On day 91, Sox2⁺/Tbr2⁻ progenitors tended to localize farther from the ventricular surface than Sox2⁻/Tbr2⁺ progenitors (Right). ***P < 0.001, Mann-Whitney test. Red line, median. (J–M) Pax6⁺ p-Vimentin⁺ progenitors had a long basal process extending toward the pia but not an apical process (J and J′), whereas these progenitors were negative for Tbr2 (K and K′). A majority (>70%) of these SVZ progenitors possessing a basal process showed a horizontal type of cleavage angle (60–90°; L and M) (n = 37). (Scale bars, 100 μm in D; 25 μm in E; 50 μm in G, J, and K; 10 μm in L.) Bars in graph, SEM. Nuclear counter staining (blue), DAPI.