Table 1.
Microneutralization and HAI assay.
| Virus(a) | NT50 (µg/ml)(b) | HAI (µg/ml)(c) |
|---|---|---|
| pH1N1 | 1.46 | 0.78 |
| TX H1N1 | 1.26 | 0.78 |
| NC H1N1 | 4.56 | 3.12 |
| PR8 H1N1 | 145.6 | 50 |
| H3N2 | >200* | ND |
| IBV | >200* | ND |
(a)Viruses used in this assay: A/California/04/09 H1N1 (pH1N1), A/Texas/36/91 H1N1 (TX H1N1), A/New Caledonia/20/99 H1N1 (NC H1N1), A/Wyoming/3/03 H3N2 (H3N2), A/Puerto Rico/08/34 H1N1 (PR8 H1N1), or B/Brisbane/60/08 (IBV).
(b)MDCK cells were infected (100 PFU) with the indicated viruses, which were pre-incubated with 2-fold serial dilutions (starting concentration of 200 µg/ml) of the hmAb KPF1. At 48–72 h p.i., cells were stained with crystal violet and the NT50 was determined using sigmoidal dose response curves. Mock-infected cells and viruses in the absence of hmAbs were used as internal controls. *Highest amount of hmAb without detectable neutralizing effect.
(c)HAI assays were performed using 2-fold serial dilutions (starting concentration of 200 µg/ml) of KPF1 and 4 hemagglutinating units (HAU) of the indicated viruses. HAI titers were determined by adding 0.5% turkey RBCs to the virus-hmAb mixtures and defined as the minimum amount of hmAb that completely inhibited hemagglutination.