Table 2.
Antiviral activity of UV-4B in a virus yield reduction assay format varies with INFV strain in MDCK cells.
| IC50 UV-4B (μM)
a
|
IC50 oseltamivir (μM)
a
|
|||||||
|---|---|---|---|---|---|---|---|---|
| Influenza strain | A | B | C | Average | A | B | C | Average |
| A/Texas/36/91 (H1N1) | >125 | >125 | – | >125 | 0.63 | 1.32 | – | 0.975 |
| A/California/07/09 (H1N1) | >125 | >125 | – | >125 | 3.99 | 1.91 | – | 2.95 |
| A/Mississippi/3/2001 (H1N1) | >125 | >125 | – | >125 | 0.173 | 0.069 | – | 0.121 |
| A/Mississippi/3/2001 H275Y (H1N1) | >125 | >125 | – | >125 | >500 | >500 | – | >500 |
| A/Hong Kong/68 (H3N2) | 5.98 | 6.04 | – | 6.01 | 0.673 | 0.423 | – | 0.548 |
| A/Perth/16/2009 (H3N2) | 60.5 | 67.2 | – | 63.9 | 1.55 | 3.83 | – | 2.69 |
| A/Victoria/361/2011 (H3N2) | 2.45 | 5.05 | – | 3.75 | 1.93 | 2.06 | – | 1.995 |
| A/Victoria/3/75 (H3N2) | >250 | 90.9 | 79.0 | >84.9 | 0.151 | 0.137 | 0.131 | 0.140 |
| A/Philippines/2/82 (H3N2) | >250 | >250 | >250 | >250 | 7.27 | 31.3 | 6.22 | 14.9 |
| B/Lee/40 | >125 | >125 | – | >125 | 16.4 | 17.2 | – | 16.8 |
| B/Brisbane/60/2008 | >125 | >125 | – | >125 | 0.657 | 0.391 | – | 0.524 |
| B/Wisconsin/01/2010 | >125 | >125 | – | >125 | 3.20 | 0.98 | – | 2.09 |
Cells were seeded in 24-well plates and incubated with two-fold serial dilutions of UV-4B, starting at 125 μM for 1 h. Cells were infected with INFV for 1 h after which medium was added and cells were incubated for 4 d. Harvested supernatants were stored at −80 °C and thawed for titer evaluation in MDCK cells using a TCID50 assay. Titers for each dilution were plotted against the UV-4B concentration and data points were fitted using a 4-PL algorithm.
IC50 data shown are the results for individual experiments (A–C), each as the average of 2–3 replicates. Results shown as greater than (>) are the highest concentration tested. –: not determined.