We first noted that the SCZ hGPCs manifested an aberrant pattern of migration upon neonatal transplantation. Normal control hGPCs invariably expanded through the white matter before colonizing the cortical gray matter (Figure 2A), as we have previously noted in both fetal tissue- and hiPSC GPC-engrafted shiverer mice (Wang et al., 2013; Windrem et al., 2008). In contrast, SCZ GPCs preferentially migrated earlier into the gray matter in shiverer mice, with large numbers traversing without stopping in the callosal white matter (n=4 lines from 4 different patients, each with >3 mice/patient, each vs. paired controls) (Figure 2B; Figure S2). This resulted in significantly fewer donor hGPCs in the white matter of shiverers engrafted with SCZ GPCs (Figures 2H–2I; Figure S2). Importantly, this was associated with substantially diminished central myelination in these mice, as reflected by both MBP immunostaining (Figures 2C–D and 2E–F) and myelin luminance (Figure 2G).
