Fig. 1. Formation and expression pattern of embryoid bodies (EBs). (A) EBs were differentiated for 10 days in methylcellulose with serum (FBS) or with two serum-free substitutes, knockout SR (SR1) or BIT 9500 (SR2). A single representative EB is shown for each case, as is the plating efficiency. (B) Total RNA from day 8 EBs differentiated in FBS, SR1 or SR2 (as indicated) was monitored by semi-quantitative RT/PCR for expression of EKLF, GATA1, adult ßmaj globin, embryonic ßh1 globin and HPRT.