(A) Time course of extracellular (○) and cell-associated (•) radioacivity in CD34⁺ cells. After a 2-hour incubation with radiolabeled ODN/DOSPER complexes the medium was removed and cells were resuspended in fresh medium. Radioactivity was measured at indicated time points by liquid scintillation counting. (B) Time course of cell-associated full-length ODN (○). The proportion of full-length ODN to the whole cell-associated radioactivity as determined by PhosphorImager analysis of a polyacrylamide gel is shown as a function of time by (▵). Multiplication of this function with the function of cell-associated radioactivity (•) resulted in the curve indicating the time course of cell-associated full-length ODN.