Reproducing SIVΔnef vaccine correlates of protection: trimeric gp41 antibody concentrated at mucosal front lines.

TitleReproducing SIVΔnef vaccine correlates of protection: trimeric gp41 antibody concentrated at mucosal front lines.
Publication TypeJournal Article
Year of Publication2016
AuthorsVoss JE, Macauley MS, Rogers KA, Villinger F, Duan L, Shang L, Fink EA, Andrabi R, Colantonio AD, Robinson JE, R Johnson P, Burton DR, Haase AT
Date Published10/23/2016

Vaccination with SIVmac239Δnef provides robust protection against subsequent challenge with wild-type simian immunodeficiency virus (SIV), but safety issues have precluded designing an HIV-1 vaccine based on a live-attenuated virus concept. Safe immunogens and adjuvants that could reproduce identified immune correlates of SIVmac239Δnef protection therefore offer an alternative path for development of an HIV vaccine. Here we describe SIV envelope trimeric gp41 (gp41t) immunogens based on a protective correlate of antibodies to gp41t concentrated on the path of virus entry by the neonatal Fc receptor (FcRn) in cervical vaginal epithelium. We developed a gp41t immunogen-monophosphoryl lipid A adjuvant liposomal nanoparticle for intramuscular (i.m.) immunization and a gp41t-Fc immunogen for intranasal immunization for pilot studies in mice, rabbits, and rhesus macaques. Repeated immunizations to mimic persistent antigen exposure in infection elicited gp41t antibodies in rhesus macaques that were detectable in FcRn+ cervical vaginal epithelium, thus recapitulating one key feature of SIVmac239Δnef vaccinated and protected animals. Although this strategy did not reproduce the system of local production of antibody in SIVmac239Δnef-vaccinated animals, passive immunization experiments supported the concept that sufficiently high levels of antibody can be concentrated by the FcRn at mucosal frontlines, thus setting the stage for assessing protection against vaginal challenge by gp41t immunization.

Alternate JournalAIDS
PubMed ID27428745
PubMed Central IDPMC5069161
Grant ListP30 AI036214 / AI / NIAID NIH HHS / United States
R01 AI102625 / AI / NIAID NIH HHS / United States
R24 OD010976 / OD / NIH HHS / United States
UM1 AI100663 / AI / NIAID NIH HHS / United States
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