5azaD/SAHA treatment increases the percentage of JAK2V617F wild-type PMF CD34⁺ cells that migrate toward CXCL12. (A) The migratory behavior of primary PMF CD34⁺ cells or PMF CD34⁺ cells reisolated after ex vivo culture in the presence of cytokines alone or cytokines plus 5azaD/SAHA was determined by the ratio of the number of cells recovered from the lower compartment to the total number of cells loaded in the upper compartment of a 6.5-mm diameter, 5-μm pore Transwell plate (n = 7). *P < .05. JAK2V617F-positive migrating cells were further assayed in semisolid media and analyzed for the JAK2V617F mutation using nested allele-specific PCR (n = 4). The percentage (B) and number (C) of JAK2V617F wild-type colonies (CFU-GM plus BFU-E plus CFU-Mixed) that migrate toward CXCL12 from cultures treated with cytokines plus 5azaD/SAHA was significantly greater than that observed from cultures exposed to cytokines alone or primary PMF CD34⁺ cells. *P < .05; **P < .01; ***P < .001.