marker GFAP was only present in less-neuronally committed cells (Figure S1C). We found a marked trend of decrease of VZ-like area during hMGEOs development. While VZ-like area at early stages consisted of over 10 layers of stratified SOX2+ nucleus, the thicknesses of VZ-like area decreased during further development. By day 71, only 3 or 4 layers of SOX2+ progenitors were identifiable within the VZ-like area (Figure 2A-2C). We found that the diameter of VZ-like area decreased from an average of 59.64 ± 2.64 μm on day 22 to 38.32 ± 1.45 μm on day 44, and 30.55 ± 1.33 μm on day 71 (Figure 2D). Although the overall thickness of VZ-like area in hMGEOs was less than that in the developing human brain, the observed trend is consistent with previous reports in human fetal brain tissues (Hansen et al., 2013).
