Figure 4.

Added granulocyte/monocyte differentiation factors do not alter GATA-2-mediated differentiation programs. (A) FDCP-mix clones were differentiated in the presence of exogenous G/GM-CSF [provided by 15% (vol/vol) lung-conditioned medium] and low IL-3 (0.01 ng/ml). The morphology of differentiated cells was determined (see above), and early and late granulocytes were scored separately. Promyeloctes and myelocytes were scored as early granulocytes while metamyelocytes and more mature granulocytes were scored as late granulocytes. As cells mature from blasts to early granulocytes, the cytoplasmic/nuclear ratio becomes larger while the cytoplasm becomes less basophilic and granules begin to appear within it. Progressive maturation to late granulocytes is characterized by a further reduction in the size of the cell, a marked condensation of the chromatin, and a segmented nucleus. The fully mature granulocyte has a very lightly stained cytoplasm with no granules present. (Top) Typical photomicrographs of wild-type FDCP-mix A4 cells, either untreated or differentiated in the presence of G/GM-CSF but the absence of β-estradiol, or differentiated in the presence of G/GM-CSF and β-estradiol. (Bottom) The morphology of the A4 GATA-2/ER no. 4 cells cultured under the same conditions. (B) Summary of the number of each cell type expressed as a percentage of the total cell number for A4 GATA-2/ER no. 4 cells in the absence (open bars) and presence (solid bars) of β-estradiol. (Bl) Blasts; (EG) early granulocytes; (LG) late granulocytes; (MØ) monocytes.