Retention of the CD34 antigen by cells grown on MS5 cells.

CD34⁺CD38^low cells were cultured 4 days in the presence (left panels) or in the absence (right panels) of MS5 cells. The dot plot analysis of cells labeled concomitantly with monoclonal antibodies against CD34 and CD38 is presented in the upper panel (A). The quadrant limits have been set according to labeling with control antibodies. The lower panel (B) visualizes the proportion of CD34⁺ cells within each cell generation as defined by CFSE distribution. In the absence of MS5 cells (B, right) at least 50% of cells were CD34⁻, whereas more than 75% cells dividing on MS5 cells retained the CD34 antigen (B, left).