Bright field microscopy images of the various stages of oligodendrocyte differentiation from induced pluripotent stem cells of the BC1 line.

(A) The undifferentiated cells grew in colonies on a mouse embryonic fibroblast feeder layer, (B) Embroid bodies (EBs) were formed by suspending the undifferentiating cells in culture on ultra-low adherence plates, (C) 15-day EBs were plated on matrigel, leading to the extension of cells of neuroectodermal lineage. Upon passaging, these neural progenitors grew in a monolayer and were subsequently differentiated to glial progenitors (D) stage. Addition of platelet derived growth factor-AA (PDGF-AA) to the media led to glial progenitors (GPs) transitioning into the (E) oligodendrocyte progenitor (OP) stage, displaying a rounded morphology with multiple filopodial extensions. (F) Terminal differentiation was induced by the removal of PDGF-AA, leading to the appearance of mature oligodendrocytes displaying characteristic branching. Scale bars- A-B: 300 μm, C-F: 80 μm