Correlation of lentiviral vector copy number with EGFP-positive cells in bone marrow of mice that received a transplant ex vivo
| . | A2UCOE . | SFFV . | CMV . |
|---|---|---|---|
| Mean % of EFGP-positive cells, n=5 | 25.6 | 10.2 | 4.1 |
| Mean vector copy number per cell, n=5 | 0.25 | 0.92 | 3.7 |
| Ratio of EGFP expression/copy number | 1/1 | 1/9 | 1/90 |
| . | A2UCOE . | SFFV . | CMV . |
|---|---|---|---|
| Mean % of EFGP-positive cells, n=5 | 25.6 | 10.2 | 4.1 |
| Mean vector copy number per cell, n=5 | 0.25 | 0.92 | 3.7 |
| Ratio of EGFP expression/copy number | 1/1 | 1/9 | 1/90 |
The average percentage of EGFP-positive ex vivo–manipulated bone marrow cells (Figure 4A) was correlated with the average A2UCOE-, SFFV-, and CMV-EGFP lentiviral vector copy number (Figure 5B). A ratio of average EGFP-positive cells to vector copy shows a 1:1 correlation in the case of A2UCOE-EGFP–transduced bone marrow but only 1:9 and 1:90 in the case of the SFFV- and CMV-EGFP vectors. This suggests that the A2UCOE negates transgene silencing to which the SFFV and especially the CMV viral promoters are highly prone.