CFSE-labeled mononuclear cell adhesion to E-CFCs. Representative experiments showing (left) the cytofluorimetric analysis of unstained peripheral blood mononuclear cells (negative control) and (right) the number of CFSE-labeled mononuclear cells bound by E-CFCs (A) in a healthy control and (B) in a patient with JAK2^V617F-positive E-CFCs. (C) Percentages of mononuclear cells adherent to normal E-CFCs (plot 1, mean values ± SEM of 4 healthy controls), to JAK2 wild-type E-CFC (plot 2, mean values ± SEM of 2 patients), and to JAK2^V627F-mutated E-CFCs (plot 3, mean values ± SEM of 4 patients). (D) RNA expression (RT-PCR) of CD45, CD11b, and GAPDH (internal control) in E-CFCs recovered from the adhesion assay, at early or late passages. Lane 1 shows peripheral blood mononuclear cells (positive control); lanes 2 and 3, JAK2 wild-type E-CFCs isolated from a patient with MPN at passages I and IV; lanes 4 and 5, JAK2^V617F E-CFCs at passages I and IV. FITC, fluorescein isothiocyanate; MW, molecular weight marker (50 base pair); GAPDH, glyceraldehyde-3-phosphate dehydrogenase.