A bone marrow sample (53-year-old male AML:M4) was stained with CD34(PE-Cy5), AC133(PE). CD90 (FITC) as well as isotype control antibodies conjugated with PE-Cy5, PE, FITC. (Top left) The gate on forward versus side scatter (1) contained the leukemic blast cell population (10% probability dot plot). (Top right) Expression of CD34 and AC133 on gated (R1) cells is shown. (Bottom right) Expression of CD90 in R2 (dotted line) versus R3. (Bottom left) The pattern of IgG-PE-Cy5 and IgG-PE isotype MoAb expression on the R1 population.