induction of primitive myelogenesis from human pluripotent stem cells(a) top panel: example image depicting the typical formation of cystic EBs bound by a single cell layer. lower panel: example of neuralized spheroid EB structures. Scale bars: 200μm. (b) typical appearance of endothelial lawns emerging from plated cystic EBs (on PDL coated plastic). Phase panels display the island formations with raised edges (left), and the progressive merger of such edges into raised ropes. Subsequent panels depict staining for VE-Cadherin (green), and c-kit (magenta). Scale Bars: 80μm. (c) higher magnification of raised structures surrounding islands (phase), staining for CD41 (green), and CD235a (magenta). Scale bar: 25μm. (d) after 2 weeks in suspension culture, cystic EBs can be plated to PDL coated plastic (left, phase contrast. Scale bar: 200μm), and large domains stain positive for the nucleus-localized transcription factor PU.1 (right, green). (e) Delamination of grape-like structures towards the luminal side from YS-EBs (red arrowheads, top left and right, scale bars:40 μm and 25μm, respectively). Putative myeloid cells are seen delaminating outward into the suspension medium (red arrowhead, bottom left, scale bar: 25μm). Homogeneous population of round motile cells seen delaminating and spreading away from the source YS-EB (Bottom right, scale bar: 80μm).
