Figure 3.

Presence of residual plasmids in transduced CD34⁺ cells. We hypothesized that transduced CD34⁺ cells with lentiviral vectors contain vector plasmids which were utilized in vector preparation. Residual plasmids were evaluated in all the samples using ampicillin resistance gene-specific probe/primers which detect plasmids but not integrated provirus. The plasmid signals were 95-fold more detected in transduced CD34⁺ cells, as compared with granulocytes and lymphocytes 6 months after transplantation.