Fig. 8. Morphology and results of flow cytometric analysis of mouse Rex1/Oct3/4 double-knock-in ES cells cultured in different serum-free media under puromycin selection (selection for Oct3/4 expression). (A) Morphology and GFP fluorescence of cells cultured in GMEM supplemented with KSR, ACTH and LIF (above) and those cultured in N2B27 medium supplemented with Bmp4 and LIF (below). (B) Flow cytometric analysis of cells cultured in GMEM+FCS, +LIF (left), in GMEM+KSR, +ACTH, +LIF (center) and in N2B27 medium +Bmp4, +LIF (right). Scale bar: 100 µm.