Figure 9: 46B8 induces ADCC via both WT and mutant B/Brisbane/60/2008 HAs.

(a) A549 cells infected with WT or mutant B/Brisbane/60/2008 viruses were labelled with 46B8 prior to incubation with NK cells. NK cell activation (left panel) and target cell lysis (right panel) were presented as the frequency of CD107a⁺ cells and the percent of LDH release, respectively. The assays were done in duplicate. Results are representative of three independent experiments. (b,c) DBA/2 J mice were infected intranasally with a minimum lethal dose of the WT or mutant B/Brisbane/60/2008 viruses. At 72 h post infection, mice received a single treatment of 46B8, 46B8 N297G or a control IgG intravenously at 15 mg kg⁻¹. (b) Survival curves. Each group contains eight mice. Log-rank tests of 46B8- versus control IgG-treated groups for all viruses, 46B8 N297G- versus control IgG-treated groups for WT, B1 and C2 and 46B8- versus 46B8 N297G-treated groups for A4, B1 and C2 give P<0.05. (c) Percent of average BW of survived mice as compared with the average pre-infection weight. (a: mean and s.e.m.; c: mean and s.d.)