UMMS Affiliation
Department of Medicine, Division of Preventive and Behavioral Medicine
Date
8-2012
Document Type
Article
Subjects
Antibody-Dependent Cell Cytotoxicity; Simian immunodeficiency virus
Disciplines
Immunology and Infectious Disease
Abstract
Live-attenuated strains of simian immunodeficiency virus (SIV) routinely confer apparent sterilizing immunity against pathogenic SIV challenge in rhesus macaques. Understanding the mechanisms of protection by live-attenuated SIV may provide important insights into the immune responses needed for protection against HIV-1. Here we investigated the development of antibodies that are functional against neutralization-resistant SIV challenge strains, and tested the hypothesis that these antibodies are associated with protection. In the absence of detectable neutralizing antibodies, Env-specific antibody-dependent cell-mediated cytotoxicity (ADCC) emerged by three weeks after inoculation with SIVDeltanef, increased progressively over time, and was proportional to SIVDeltanef replication. Persistent infection with SIVDeltanef elicited significantly higher ADCC titers than immunization with a non-persistent SIV strain that is limited to a single cycle of infection. ADCC titers were higher against viruses matched to the vaccine strain in Env, but were measurable against viruses expressing heterologous Env proteins. In two separate experiments, which took advantage of either the strain-specificity or the time-dependent maturation of immunity to overcome complete protection against SIV(mac)251 challenge, measures of ADCC activity were higher among the SIVDeltanef-inoculated macaques that remained uninfected than among those that became infected. These observations show that features of the antibody response elicited by SIVDeltanef are consistent with hallmarks of protection by live-attenuated SIV, and reveal an association between Env-specific antibodies that direct ADCC and apparent sterilizing protection by SIVDeltanef.
Related Resources
PubMed ID
22927823
Comments
Citation: PLoS Pathog. 2012 Aug;8(8):e1002890. Epub 2012 Aug 23. Link to article on publisher's site
Copyright: © Alpert et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.