Induction of myelomonocytic differentiation by ATRA and/or G/GM-CSF in myeloid leukemia cell lines and patient samples. (A,B) Flow cytometric detection of CD11b expression using FITC-labeled mouse anti-human CD11bmAb. After 3 days of treatment with differentiating agents (as indicated), the numbers of CD11b cells (above bars) and the mean values of CD11b fluorescence intensity (red line) were determined compared with untreated control cells. Three different cell lines (A) and 3 patient samples (B) have been investigated with 10 000 (A) and 5000 (B) viable cells being analyzed in each case. IgG1-negative control levels were deducted from all values. (C,D) Morphological appearance following May-Grünwald staining of myeloid leukemia cell lines (C) and patient cells (D), which were treated with ATRA and G/GM-CSF for 5 days or untreated (control). Original magnification: × 63.
