Figure 2

Characteristics of rat bone marrow-derived EPC. Utilizing phase contrast microscopy as well EPC (Figure 2A, 20×) as rAEC (Figure 2B, 20×) showed a typical cobblestone morphology after reaching confluence. The endothelial phenotype was further confirmed by immunostaining with antibodies specific for several endothelial markers and compared with mature rAEC: EPC cultured from rat bone-marrow incorporated acetylated low-density lipoprotein (aLDL, Figure 2c, 30×) to the same extent than observed in mature rAEC (Figure 2d, 30×). Furthermore, as well EPC (Figure 2E, 30×) as rAEC (Figure 2F, 20×) uniformly expressed von Willebrand factor (vWF). Figure 2G and 2H show the flow cytometric (FACS) characteristics of EPC (red lines) compared to hL-MVEC (black lines). Staining was performed for P1H12 corresponding to CD146, CD133, the VEGF-receptor 2 (KDR) and CD106 (VCAM-1) as given in Materials and Methods.