Table 1. Influenza B HA mAbs.
| mAb | ELISA Titer (μg/ml)1 | Hemagglutination Inhibition Titer (μg/ml)2 | Pseudotype Neutralization Titer (μg/ml)3 | ||
|---|---|---|---|---|---|
| Homologous Antigen | Victoria B/Brisbane/60/2008 |
Yamagata B/Texas/6/2011 or Homologous B/Yam |
Victoria B/Brisbane/60/2008 |
Yamagata B/Wisconsin/1/2010 |
|
| B/Vic mAbs | |||||
|
BR5A1 4h8 8F4 |
3.04 | 1.10 2.47 |
>400 | 0.080 | >20 |
| BR8E12 | 3.04 | 2.47 | >400 | 0.027 | >20 |
| BR7B7 | 3.04 | 1.56 | >400 | 0.144 | >20 |
| B/Yam mAbs | |||||
| WI3E6 | 0.19 | >400 | 0.874 | >20 | 0.008 |
| WI3E8 | 0.76 | >400 | 0.874 | >20 | 0.006 |
| MA1H4 | 0.38 | >400 | 0.39 | >20 | 0.004 |
| MA3B2 | 0.76 | >400 | 1.56 | >20 | 5.40 |
| MA3B8 | 0.38 | >400 | 0.78 | >20 | 0.016 |
| Cross-reactive mAbs | |||||
| CR2F113 | 1.52 | 0.55 | 0.10 | 0.201 | 0.070 |
| CR2D5 | 1.52 | >400 | >400 | >20 | >20 |
1 The end-point ELISA titer was defined as the lowest antibody concentration that gave an absorbance value at 405 nm greater than 0.05. ELISA binding was determined using B/Brisbane/60/2008 antigen for BR5A1, BR8E12, BR7B, CR2F11, and CR2D5; B/Wisconsin/1/2010 antigen for WI3E6 and WI3E8; and B/Massachusetts/02/2010 antigen for MA1H4, MA3B2, and MA3B8.
2 Hemagglutination inhibition (HI) titer was defined as the lowest antibody concentration that inhibited influenza B antigen agglutination of chicken red blood cells. B/Yamagata antigens used for HI were B/Texas/6/2011 for the B/Brisbane mAbs, B/Wisconsin/1/2010 for the B/Wisconsin mAbs, and B/Massachusetts/02/2010 for the B/Massachusetts and cross reactive mAbs.
3 Pseudotype neutralization titer was defined as the antibody concentration resulting in a 95% reduction in relative luciferase units of a retrovirus pseudotype expressing the indicated influenza B HA.