Human Non-neutralizing HIV-1 Envelope Monoclonal Antibodies Limit the Number of Founder Viruses during SHIV Mucosal Infection in Rhesus Macaques

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Antibodies specifically recognize antigenic sites on pathogens and can mediate multiple antiviral functions through engagement of effector cells via their Fc region. Current HIV-1 vaccine candidates induce polyclonal antibody responses with multiple antiviral functions, but do not induce broadly neutralizing antibodies. An improved understanding of whether certain types of non-neutralizing HIV-1 specific antibodies can individually protect against HIV-1 infection may facilitate vaccine development. Here, we test whether non-neutralizing antibodies with multiple antiviral functions mediated through FcR engagement and recognition of virus particles or virus-infected cells can limit infection, despite lacking classical virus neutralization activity. In a passive antibody infusion-rhesus macaque challenge model, we tested the ability of non-neutralizing monoclonal antibodies to limit virus acquisition. We demonstrate that two different types of non-neutralizing antibodies, one that recognizes both virus particles and infected cells (7B2) and another that recognizes only infected cells (A32) were capable of decreasing the number of transmitted founder viruses. Further, we provide the structure of 7B2 in complex with the gp41 cyclical loop motif, a motif critical for entry. These findings provide insights into the role that antibodies with antiviral properties, including virion capture and FcR mediated effector function, may play in protecting against HIV-1 acquisition.

Vyšlo v časopise: Human Non-neutralizing HIV-1 Envelope Monoclonal Antibodies Limit the Number of Founder Viruses during SHIV Mucosal Infection in Rhesus Macaques. PLoS Pathog 11(8): e32767. doi:10.1371/journal.ppat.1005042
Kategorie: Research Article
prolekare.web.journal.doi_sk: https://doi.org/10.1371/journal.ppat.1005042

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