Cytospins of cells from type A, B, and C colonies with May-Grünwald Giemsa stain.

Cells in type A colonies are largely undifferentiated with a high nuclear/cytoplasmic ratio, while cells from type C colonies generally demonstrate evidence of monocytic or granulocytic lineage differentiation. Type B colonies are a mixture of undifferentiated and more mature cells. Original magnification, × 40.