Fig. 5

PaCSs are poorly represented in AML whereas are present in MDS cells. a–c BM of AML patients. No PaCSs are found in blast cells shown in (a) (asterisk) and (b), while a small FK1-reactive PaCS (arrowheads) is being formed in a ribosome-rich area of another blast (c), also showing focal differentiation of endoplasmic reticulum (arrows). rm reactive macrophage. d BM micromegakaryocyte of a patient with MDS (refractory anemia with multilineage dysplasia) showing small peripheral PaCSs (arrows), some of which enter into blebs and free vesicles (d1). e PB neutrophil granulocyte of a patient with MDS (refractory anemia with multilineage dysplasia) with several PaCSs, one of which is enlarged in the inset to recognize FK1 immunogold reactivity. Note in the lower right corner (arrowhead) a PaCS in an adjacent platelet