Fig. 1

The monoclonal antibody 14F8 recognizes a unique vulnerable neutralization epitope on the NiV-G protein. a Kinetics of the binding of 14F8 to the NiV-G protein assessed by SPR on Biacore. The raw data are displayed in color, whereas the fitted data are shown in black. Comparison of the neutralization activities of 14F8, m102.4, and a nonspecific control antibody (anti-VSV-G, 8G5F11) against NiV pseudoviruses (b) and HeV pseudoviruses (c) in Ephrin B2-expressing 293T cells. Data represents percent neutralization against varying antibody concentrations; representative of three replicates. The data were processed via the inhibitor vs. response model, and the IC50 values were calculated. The fitted curves are displayed in the figure. d Neutralizing activity of 14F8, m102.4, and the control antibody against NiV as measured by a Luminex competitive inhibition assay. The data represent the mean fluorescence intensity (MFI) against varying antibody concentrations and are representative of two replicates. e Crystal structure of the 14F8 Fab–NiV-G complex. Residues from the 14F8 CDRH and CDRL and the framework regions (FRH) of the 14F8 heavy chain that are involved at the interaction interface are displayed as colored sticks. f Detailed interactions between 14F8 Fab and NiV-G. 14F8 heavy and light chains and belonging residues are shown in cyan and green, respectively, and NiV-G is shown in gray. The residues in NiV-G are in orange. The red dashed lines represent hydrogen bonds. g Contact surface of NiV-G with 14F8 (red) and the Ephrin B2 receptor (39) (blue), mapped on NiV-G (gray). h Alignment of the crystal structures of 14F8 Fab–NiV-G and the Ephrin B2-NiV-G complex (PDB ID: 2VSM). NiV-G, gray; 14F8 heavy and light chains, cyan and green, respectively; Ephrin B2, red. i Binding sites of 14F8, HENV-32, and nAH1.3