Fig. 2

CD133 and EpCAM surface levels in MDA-MB-231 sub-populations. MDA-MB-231 cells were subjected to positive immunomagnetic separation after labeling with MicroBeads-conjugated anti-CD133 antibody followed by the positive selection through column of cells labeled with MicroBeads-conjugated anti-EpCAM antibody. Surface levels of CD133 and EpCAM were evaluated in all sub-populations after double labelling with a PE-conjugated anti-CD133 and with a FITC-conjugated anti-EpCAM antibody. The expression of each antigen is shown on a frequency distribution histogram (count vs. PE or FITC signal) in which the MFI of the entire population is reported. The red filled histograms represent positive staining for CD133 or EpCAM and the open histograms, outlined by gray lines, show staining with matched isotype antibodies. The dot plot analysis was used to assess the enrichment in CD133⁻/EpCAM⁻, CD133⁻/EpCAM⁺, CD133⁺/EpCAM⁻ and CD133⁺/EpCAM⁺ cells in all subsets and the percentage of the main cell phenotype in each enriched sub-population is indicated. The data are indicative of three separate experiments