Figure 5.

Antibodies elicited by BG505 NFL trimers target holes in the N-glycan shield. (A) Cartoon representation of the BG505 SOSIP trimer (PDB id 5CEZ) depicting known N-glycan holes at positions 289, 241, and 230, respectively. The backbone for gp120 is colored gray and gp41 is colored green. The amino acids at the position of the glycan holes are shown as red spheres and ordered glycans as seen in the crystal structure are shown as cyan spheres. (B) Neutralization ID₅₀ titers at the final bleed point (P4) against a panel of autologous tier 2 BG505 viruses that have the glycans restored at positions 230 and 289 are shown. Elicitation of antibodies against the glycan hole at position 241 was probed against the parent virus MG505 that lacks the glycan at position 241 and the MG505 K241S variant that restores a serine residue at position 241 as it exists in wild-type BG505 virus. (C) Geometric mean of neutralization ID₅₀ titers showing reduction in neutralization against a panel of pseudoviruses with N-glycans restored.