A representative FACS analysis of human cord blood hematopoietic cells after transduction with PA317/EGFP1 supernatants for 4 consecutive days. Cells were stained at day 4 with phycoerythrin-labeled anti-CD34 monoclonal antibody (Clone 8G12; Becton Dickinson, San Jose, CA). The dot plot represents CD34 versus EGFP expression in the target cells. Percentages of analyzed events are shown for each cell subpopulation.