packaging plasmid | envelope plasmid | transfer plasmid | RNA/ml | TU/ml | pg p24/ml |
|---|
+ | + | + | 6.18 ± 1.71 × 109 | 1.07 ± 0.53 × 107 | 4.10 ± 2.05 × 105 |
+ | + | - | below detection limit | below detection limit | 2.10 ± 0.64 × 105 |
+ | - | + | 2.36 ± 0.63 × 1010 | below detection limit | 1.27 ± 0.32 × 105 |
- | + | + | 8.04 ± 1.64 × 106 | below detection limit | below detection limit |
- Lentiviral vectors were produced in parallel in cell culture dishes by triple transient transfection with transfer, envelope and packaging plasmids. Omission of a plasmid is indicated. RNA equivalents (RNA/ml), transducing units (TU/ml) and p24 concentration (pg p24/ml) were determined after concentration of LV by low-speed centrifugation. For the CH-eGFP-WS vector, the titer was measured with all three methods. In the absence of the packaging plasmid, encoding for structural proteins, the RNA titer decreased 1000-fold while p24 and TU titers were below detection limit. Omission of the envelope plasmid during the vector production resulted in p24 and RNA titers comparable with those of a normal production albeit with a non-detectable functional titer. Vector production without transfer plasmid only yielded a positive p24 titer. Mean values ± standard deviation for 3 measurements of the same sample are shown.
