Table 1. Evolution of influenza virus reverse genetics.
| Year | Milestone | Helper Virus | Plasmids |
|---|---|---|---|
| 199419 |
RNA pol I is manipulated to transcribe influenza viral RNA |
Yes |
|
| 199920 |
Viruses are generated entirely from cloned cDNA encoding 8 genes |
No |
17 |
| 199922 |
Reduction in plasmid number leads to higher efficiency transfections and increased viral titers |
No |
12 |
| 200023 |
Introduction of RNA pol I/II system for influenza virus reverse genetics |
No |
8 |
| 200524 |
Three-plasmid system: 1) vRNA-transcription units, 2) polymerase proteins, and 3) NP |
No |
3 |
| 200925 | One-plasmid system produces high titers in chicken cells | No | 1 |