Structural and Biochemical Characterization of Cysteinylation in Broadly Neutralizing Antibodies to HIV-1.

Autor: Omorodion O; Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA 92037, USA; IAVI Neutralizing Antibody Center, The Scripps Research Institute, La Jolla, CA 92037, USA; Consortium for HIV/AIDS Vaccine Development (CHAVD), The Scripps Research Institute, La Jolla, CA 92037, USA., Wilson IA; Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA 92037, USA; IAVI Neutralizing Antibody Center, The Scripps Research Institute, La Jolla, CA 92037, USA; Consortium for HIV/AIDS Vaccine Development (CHAVD), The Scripps Research Institute, La Jolla, CA 92037, USA; Skaggs Institute for Chemical Biology, The Scripps Research Institute, La Jolla, CA 92037, USA. Electronic address: wilson@scripps.edu.
Jazyk: angličtina
Zdroj: Journal of molecular biology [J Mol Biol] 2021 Dec 03; Vol. 433 (24), pp. 167303. Date of Electronic Publication: 2021 Oct 16.
DOI: 10.1016/j.jmb.2021.167303
Abstrakt: Antibodies with exceptional breadth and potency have been elicited in some individuals during natural HIV-1 infection. Elicitation and affinity maturation of broadly neutralizing antibodies (bnAbs) is therefore the central goal of HIV-1 vaccine development. The functional properties of bnAbs also make them attractive as immunotherapeutic agents, which has led to their production and optimization for passive immunotherapy. This process requires in vitro manufacturing and monitoring of any heterogeneous expression, especially when subpopulations of antibodies are produced with varying levels of biological activity. Post-translational modification (PTM) of antibodies can contribute to heterogeneity and is the focus of this study. Specifically, we have investigated cysteinylation in a bnAb lineage (PCDN family) targeting the N332-glycan supersite on the surface envelope glycoprotein (Env) of HIV-1. This PTM is defined by capping of unpaired cysteine residues with molecular cysteine. Through chromatography and mass spectrometry, we were able to characterize subpopulations of cysteinylated and non-cysteinylated antibodies when expressed in mammalian cells. The crystal structures of two PCDN antibodies represent the first structures of a cysteinylated antibody and reveal that the cysteinylation in this case is located in CDRH3. Biophysical studies indicate that cysteinylation of these HIV-1 antibodies does not interfere with antigen binding, which has been reported to occur in other cysteinylated antibodies. As such, these studies highlight the need for further investigation of cysteinylation in anti-HIV and other bnAbs.
Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
(Copyright © 2021 The Author(s). Published by Elsevier Ltd.. All rights reserved.)
Databáze: MEDLINE