Broadly neutralizing hemagglutinin stalk-specific antibodies require FcR interactions for protection against influenza virus in vivo

David J. Dilillo, Gene S. Tan, Peter Palese, Jeffrey V. Ravetch

Research output: Contribution to journalArticlepeer-review

626 Scopus citations

Abstract

Neutralizing antibodies against influenza viruses have traditionally been thought to provide protection exclusively through their variable region; the contributions of mechanisms conferred by the Fc domain remain controversial. We investigated the in vivo contributions of Fc interactions with their cognate receptors for a collection of neutralizing anti-influenza antibodies. Whereas five broadly neutralizing monoclonal antibodies (bNAbs) targeting the conserved stalk region of hemagglutinin (HA) required interactions between the antibody Fc and Fc receptors for IgG (FcRs) to confer protection from lethal H1N1 challenge, three strain-specific monoclonal Abs (mAbs) against the variable head domain of HA were equally protective in the presence or absence of FcR interactions. Although all antibodies blocked infection, only anti-stalk bNAbs were capable of mediating cytotoxicity of infected cells, which accounts for their FcR dependence. Immune complexes generated with anti-HA stalk mAb efficiently interacted with FcRs, but anti-HA head immune complexes did not. These results suggest that FcR binding capacity by anti-HA antibodies was dependent on the interaction of the cognate Fab with antigen. We exploited these disparate mechanisms of mAb-mediated protection to reengineer an anti-stalk bNAb to selectively enhance FcR engagement to augment its protective activity. These findings reveal a previously uncharacterized property of bNAbs and guide an approach toward enhancing mAb-mediated antiviral therapeutics.

Original languageEnglish
Pages (from-to)143-151
Number of pages9
JournalNature Medicine
Volume20
Issue number2
DOIs
StatePublished - Feb 2014

Fingerprint

Dive into the research topics of 'Broadly neutralizing hemagglutinin stalk-specific antibodies require FcR interactions for protection against influenza virus in vivo'. Together they form a unique fingerprint.

Cite this