Focal accumulation of aromaticity at the CDRH3 loop mitigates 4E10 polyreactivity without altering its HIV neutralization profile

Abstract

Summary Broadly neutralizing antibodies (bnAbs) against HIV-1 are frequently associated with the presence of autoreactivity/polyreactivity, a property that can limit their use as therapeutic agents. The bnAb 4E10, targeting the conserved Membrane proximal external region (MPER) of HIV-1, displays almost pan-neutralizing activity across globally circulating HIV-1 strains but exhibits nonspecific off-target interactions with lipid membranes. The hydrophobic apex of the third complementarity-determining region of the heavy chain (CDRH3) loop, which is essential for viral neutralization, critically contributes to this detrimental effect. Here, we have replaced the aromatic/hydrophobic residues from the apex of the CDRH3 of 4E10 with a single aromatic molecule through chemical modification to generate a variant that preserves the neutralization potency and breadth of 4E10 but with reduced autoreactivity. Collectively, our study suggests that the localized accumulation of aromaticity by chemical modification provides a pathway to ameliorate the adverse effects triggered by the CDRH3 of anti-HIV-1 MPER bnAbs.

A two‐step mechanism for the binding of the HIV‐1 MPER epitope by the 10E8 antibody onto biosensor‐supported lipid bilayers

“…The neutralizing capacity of the produced Fabs was assessed in pseudovirus‐based assays as described in previous works [20,26]. HIV‐1 pseudovirus was produced by transfection of human kidney HEK293T cells with the full‐length Env clones JRCSF (kindly provided by Jamie K. Scott and Naveed Gulzar, Simon Fraser University, BC, Canada) IIIB or PVO.4 (both obtained from the AIDS Research and Reference Reagent Program (ARRRP)).…”

“…HIV‐1 pseudovirus was produced by transfection of human kidney HEK293T cells with the full‐length Env clones JRCSF (kindly provided by Jamie K. Scott and Naveed Gulzar, Simon Fraser University, BC, Canada) IIIB or PVO.4 (both obtained from the AIDS Research and Reference Reagent Program (ARRRP)). Fab polyreactivity was assayed using HIV‐1 negative human epithelial HEp‐2 (Kallestad ANA/HEp‐2) and quantified following previously described protocols [26].…”

“…HIV-1 pseudovirus was produced by transfection of human kidney HEK293T cells with the full- . Fab polyreactivity was assayed using HIV-1 negative human epithelial HEp-2 (Kallestad ANA/HEp-2) and quantified following previously described protocols [26].…”

“…The neutralizing capacity of the produced Fabs was assessed in pseudovirus-based assays as described in previous works [20,26]. HIV-1 pseudovirus was produced by transfection of human kidney HEK293T cells with the full- .…”

Binding Promiscuity of Therapeutic Factor VIII

“…Although binding promiscuity is an inherent property of many proteins, notorious engineering efforts are being perform to decrease the polyreactivity of therapeutic Abs in order to improve their pharmacological profile, while maintaining their therapeutic functions (105,106). In the case of FVIII, the substitution of positively charge residues in FVIII-C1 and C2 domains increases the half-life of the protein in FVIII/VWF-KO mice (107).…”