CD34⁺ cells were incubated for 14 days in complete medium. Medium was supplemented with FL at 25 ng/mL plus IL-3 at 50 ng/mL to promote monocytic differentiation or with G-CSF plus SCF, both at 50 ng/mL, to promote neutrophilic differentiation. At days 0, 5, and 10, control oligonucleotides (CO) or antisense RB oligonucleotides (AS2), respectively, were added, each time at a concentration of 5.0 μmol/L. At day 14, cell morphology was determined after May-Grünwald-Giemsa staining of cytospin preparations. Results on morphology are the mean percentages of 200 counted cells from three separate experiments ± SEM. Total cell number was scored at day 14 and values are thousands of cells per milliliter ± SEM.