Fig. 4. Expression of lineage markers in response to TGFß treatment. EBs were treated with different concentrations of TGFß: (A-D) from day 3 to day 8, or (E-F) from day 13 to day 18. Expression was measured by qRT-PCR, normalized to GAPDH. Results were presented relative to expression in untreated samples. The expression of PECAM1 in control (I,K) and treated (L,N) samples was examined by immunofluorescence staining. DAPI-stained nuclei are also shown (J,M). K and N are high power magnifications of the boxed areas within I and L, respectively.