Figure 1

FACS sorting of PA6-derived Sox1 -GFP^pos neural progenitors. Neural progenitors generated by co-culturing ES cells with PA6 can be identified based on GFP reporter expression from the Sox1 locus (A, B). FACS plots showing the isolation of GFP^pos neural progenitors from GFP^neg ES cell differentiated progeny and PA6 cells (C – E). Gates were set based on plots of PA6 cells + wild type ES cells (C) and wild type ES cells alone (D). FACS sorting was performed either on day 7 (F) or day 3–4 (G). Sox1-GFP^pos cells and GFP^neg differentiated ES cell population were subsequently cultured under neuronal differentiation conditions either on PDL/laminin or in co-culture with PA6 cells. After a total of 14 days in cultures, cells were fixed and processed for immunocytochemistry. FL1 = GFP, FL2 = PE, R2 = GFP^pos neural progenitors, R5 = GFP^neg differentiated ES cells. Arrowhead points PA6-enriched cell population. Scale bar = 100 μm.