Fig. 3.

pSERS SF SIN γ-retrovector is not mobilized by the BXV1 xenotropic γ − retrovirus in EndoC-βΗ2 cells. a. GFP fluorescence level in transduced 293 T and EndoC-βΗ2 cells. 4 days after transduction with the indicated non-SIN (pPRIZ GFP) or SIN (pSERS SF GFP-IRES-ZeoR) γ-retrovector, 293 T and EndoC-βΗ2 cells were selected in zeocin for 9 days (day 4 + 9), then harvested and analyzed for GFP fluorescence by flow cytometry. The number above each diagram indicates the mean of fluorescence of the whole population of analyzed cells. The number in the diagram is the percentage of fluorescent cells. b. Conditioned medium (CM) of the transduced 293 T or EndoC-βΗ2 cells shown in A was added to « naive » 293 T cells. Transmission of zeocin resistance as a measure of γ-retrovector mobilization/trans-complementation was assessed by selecting the exposed 293 T to zeocin. GFP fluorescence was detected at various levels in most of the 293 T foci observed after their exposure to the CM of EndoC-βΗ2-pPRIZ GFP, one of them is shown. This experiment was done in duplicates, which gave similar results