Figure 3: 46B8 binds to conserved residues in the vestigial esterase domain of HA.
From: A broadly protective therapeutic antibody against influenza B virus with two mechanisms of action
(a) Negative stain EM reconstruction (grey mesh) of 46B8 Fabs in complex with the B/Victoria/504/2000 HA trimer. Side (left panel) and overhead (right panel) views show the fit of a generic Fab model and the crystal structure of an IBV HA (PDB ID 4M40) to the EM density. HA is in different shades of blue, the heavy chain of 46B8 Fab is in red and the light chain is in yellow. (b) A detailed view of the 46B8-HA contact surface. Potential 46B8-interacting residues on HA are shown as purple sticks and labelled (numbering includes the signal sequence). Colour code is the same as in a. (c) 293 T cells expressing the WT or mutant B/Victoria/504/2000 HAs were incubated with 34B5 (top panel) or 46B8 (middle and bottom panels) at pH 7.0 (top and middle panels) or 4.8 (bottom panel). The mean fluorescence intensities (MFI) from flow cytometry profiles are shown. Mock, mock transfected cells. (d) Frequency table of potential 46B8-interacting residues. A multiple sequence alignment of 12,790 human IBV HA amino-acid sequences was used to assess the genetic diversity and calculate the frequencies of potential 46B8-interacting residues.
