Effect of AML1-ETO on EPO-dependent differentiation.

(A) Distribution of cell size (forward scatter) of GFP⁺CD13⁻ cells. (B-E) Immunophenotypic profile of GFP⁺CD13⁻ cells labeled with antibodies to one other determinate as indicated. (F) Differential counts of morphology after 7 days of culture in the presence of EPO. Cells were classified according to established criteria as follows: late (L; orthochromatic normoblasts/reticulocytes); intermediate (I; polychromatic normoblasts), and early (E; all preceding stages of development). Data indicate mean ± 1 SD (n = 3). Significant difference of AML1-ETO from control cultures (GFP) is indicated: *P < .05 and †P < .01. Error bars represent 1 SD.