RT Journal Article
SR Electronic
T1 Polyclonal antibody responses to HIV Env immunogens resolved using cryoEM
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 2021.01.28.428677
DO 10.1101/2021.01.28.428677
A1 Aleksandar Antanasijevic
A1 Leigh M. Sewall
A1 Christopher A. Cottrell
A1 Diane G. Carnathan
A1 Luis E. Jimenez
A1 Julia T. Ngo
A1 Jennifer B. Silverman
A1 Bettina Groschel
A1 Erik Georgeson
A1 Jinal Bhiman
A1 Raiza Bastidas
A1 Celia LaBranche
A1 Joel D. Allen
A1 Jeffrey Copps
A1 Hailee R. Perrett
A1 Kimmo Rantalainen
A1 Fabien Cannac
A1 Yuhe R. Yang
A1 Alba Torrents de la Peña
A1 Rebeca Froes Rocha
A1 Zachary T. Berndsen
A1 David Baker
A1 Neil P. King
A1 Rogier W. Sanders
A1 John P. Moore
A1 Shane Crotty
A1 Max Crispin
A1 David C. Montefiori
A1 Dennis R. Burton
A1 William R. Schief
A1 Guido Silvestri
A1 Andrew B. Ward
YR 2021
UL http://biorxiv.org/content/early/2021/01/28/2021.01.28.428677.abstract
AB In Brief Herein, we evaluated the immunogenicity of several BG505 SOSIP-based HIV Env immunogens in the rhesus macaque animal model using a combination of serology and biophysical approaches. We applied electron cryo-microscopy for high-resolution mapping of elicited polyclonal antibody responses, which provided detailed insights into the binding modes of the most common classes of antibodies elicited by BG505 SOSIP immunogens as well as the critical differences in immunogenicity that can occur as a consequence of engineered stabilizing mutations and partial glycan occupancy at different sites.Summary Engineered ectodomain trimer immunogens based on BG505 envelope glycoprotein are widely utilized as components of HIV vaccine development platforms. In this study, we used rhesus macaques to evaluate the immunogenicity of several stabilized BG505 SOSIP constructs both as free trimers and presented on a nanoparticle. We applied a cryoEM-based method for high-resolution mapping of polyclonal antibody responses elicited in immunized animals (cryoEMPEM). Mutational analysis coupled with neutralization assays were used to probe the neutralization potential at each epitope. We demonstrate that cryoEMPEM data can be used for rapid, high-resolution analysis of polyclonal antibody responses without the need for monoclonal antibody isolation. This approach allowed to resolve structurally distinct classes of antibodies that bind overlapping sites. In addition to comprehensive mapping of commonly targeted neutralizing and non-neutralizing epitopes in BG505 SOSIP immunogens, our analysis revealed that epitopes comprising engineered stabilizing mutations and of partially occupied glycosylation sites can be immunogenic.Competing Interest StatementThe authors have declared no competing interest.