Skip to main content
. 2010 Oct 12;19(1):133–139. doi: 10.1038/mt.2010.218

Figure 5.

Figure 5

GFP expression in human erythroid cells after transduction with an insulated BGpGFP vector. To evaluate whether an HS4 insulator can protect differentiation-dependent reduction of transgene expression (position effect), human CD34+ cells were transduced with MpGFP (forward-oriented GFP-expressing vector under the control of an MSCV-LTR promoter), BGpGFP (reverse-oriented GFP-expressing vector under the control of a β-globin promoter), and BGpGFP vector containing a reverse orientation HS4 core insulator (250b HS4 R), all at MOI of 20. GFP expression in GPA+ cells was serially analyzed over days of culture. %GFP and MFIs decreased and CVs increased from cells transduced with the control MpGFP vector, showing position effects. The 250b HS4 R insulator showed lower %GFP and lower MFI (N = 3, P < 0.05 in t-test on days 13 and 20), compared to those of the uninsulated vector BGpGFP. There was no difference in CVs. CV, coefficient of variation; GFP, green fluorescent protein; HS4, hypersensitivity site 4; LTR, long-terminal repeat; MFI, mean fluorescent intensity; MSCV, murine stem cell virus.