Fig. 1: Afucosylated anti-HIV-1 bNAbs demonstrate enhanced binding to FcγRIIIa.

a Schematic representation of an IgG1 monoclonal antibody with the N-linked 297 glycan depicted in the Fc domain on both Ab heavy chains. The fucosylated complex glycan represents one of the major glycoforms (G0F) found in serum and in in vitro produced monoclonal Ab. Glyco-engineering techniques facilitate the production of antibodies with an afucosylated Fc-glycan. b Mass spectrometry based glyco-peptide analysis of anti-HIV-1 Abs produced in HEK-293F cells in the absence or presence of a decoy substrate for the fucosyltransferase (2FF). Fucosylated Ab variants (produced under standard conditions) and afucosylated variants (produced in the presence of 2FF) are depicted in dark gray and light gray respectively. c Env, FcγRIIa and FcγRIIIa binding of fucosylated (dark gray) and afucosylated (light gray) anti-HIV-1 Abs in the context of BG505 SOSIP.v4.2 as determined with ELISA in triplo. Mean OD₄₅₀ values + standard deviation are plotted at 5 µg/ml Ab concentration. Antibody titrations can be found in Supplementary Fig. 1E. Controls (PGT121 PG-LALA, afucosylated anti-SARS CoV-2 Ab COVA1-18 and absence of Ab) are depicted in white bars. Statistical differences between fucosylated and afucosylated bNAbs were determined using an ordinary one way Anova with a Šídák's multiple comparisons test and significant differences are indicated with asterisks. *p < 0.05, **p < 0.01, ***p < 0.001.