Figure 1.

H/F LV Production Causes Syncytia Formation in Packaging Cells and Cell Debris Remains in Vector Preparations

(A) 10× bright-field (left) and 488-nm fluorescent (middle and right) microscopy images of transiently transfected HEK293T cells generating either VSV-G LV (middle) or H/F LV (right) 3 days after co-transfection with respective packaging plasmids. (B) 64× confocal microscopy images of umbilical cord blood (UCB)-derived CD34⁺ cells transduced with either H/F LV (left) or VSV-G LV (right). Cytokine pre-stimulated cells were treated with either LV for 15 min, then fixed before staining for EEA1 (green), vector Gag p24 protein (red), and nuclei with Hoechst (blue).