Figure 1

Flow cytometric analysis of parental and MR-positive Cells. 43, U937 and 43MR cells were harvested and prepared for Western blot and flow cytometric (FACS) analysis. For FACS analysis, cells (1 x 10⁶) were harvested and fixed in 2% paraformalin. As negative controls, both 43 and 43MR cells were stained with Alexa 488 alone (upper right histogram) or unstained (upper left histogram). For detection of MR, 43 cells or 43^MR cells were stained with mouse monoclonal anti-MR followed by Alexa 488 conjugated goat anti-mouse secondary as previously described. The number of events acquired for each sample was 3 x 10⁴. Data shown are the relative change in mean fluorescence intensity as compared to the control, and data are representative of at least two independent experiments. For Western blot analysis, 1 x 10⁶ cells were lysed in 0.1% Triton lysis buffer and 25 μg of total protein was separated by SDS gel electrophoresis. Proteins were transferred to nitrocellulose and the blot probed with goat anti-MR and mouse anti-actin antibodies followed by Licor donkey anti-goat Ir-680 and donkey anti-mouse Ir-800 conjugated secondary antibodies.