Cytospin preparations of megakaryocytes generated from purified CD34⁺ cells cultured for 14 days in the presence of MIP-1α, IL-3, IL-6, IL-11, FL, SCF, and MGDF. Most cells displayed a CD61⁺ phenotype detected by APAAP staining. In (A) cells were treated by BFA and staining was more intense on the cells' surface. Cells in (B) were permeabilized by acetone, and a number of proplatelet structures are visible, together with CD61⁺ cells with increased ploidy.