The identity of each iPSC line was confirmed to match the parental donor fibroblasts using short tandem repeat (STR)-based DNA fingerprinting. iPSC line isolates were also karyotyped concurrently with these experiments to confirm genomic integrity. An additional well-characterized hiPSC control line, C27(Chambers et al., 2009), was also used, to ensure that our control engraftment and differentiation data were consistent with prior studies in our lab (Wang et al., 2013). Altogether, we evaluated hGPC preparations from 7 iPSC lines derived from 5 SCZ patients, and 5 iPSC lines derived from 4 control subjects (Table S1). We instructed these iPSC cells to GPC fate as previously described (Wang et al., 2013), and after >105 days in vitro (DIV) under glial differentiation conditions validated the predominant GPC phenotype of each cell population using flow cytometry for CD140a/PDGFαR (Figure S1) (Sim et al., 2011). To optimize glial differentiation in vivo, we limited transplants to those preparations in which most cells were CD140a+ GPCs, with the remainder astroglial.
