Immunization with HIV-1 gp41 subunit virosomes induces mucosal antibodies protecting nonhuman primates against vaginal SHIV challenges

Immunity. 2011 Feb 25;34(2):269-80. doi: 10.1016/j.immuni.2011.01.015.


Human immunodeficiency virus (HIV)-1 is mainly transmitted mucosally during sexual intercourse. We therefore evaluated the protective efficacy of a vaccine active at mucosal sites. Macaca mulatta monkeys were immunized via both the intramuscular and intranasal routes with an HIV-1 vaccine made of gp41-subunit antigens grafted on virosomes, a safe delivery carrier approved in humans with self-adjuvant properties. Six months after 13 vaginal challenges with simian-HIV (SHIV)-SF162P3, four out of five vaccinated animals remained virus-negative, and the fifth was only transiently infected. None of the five animals seroconverted to p27gag-SIV. In contrast, all 6 placebo-vaccinated animals became infected and seroconverted. All protected animals showed gp41-specific vaginal IgAs with HIV-1 transcytosis-blocking properties and vaginal IgGs with neutralizing and/or antibody-dependent cellular-cytotoxicity activities. In contrast, plasma IgGs totally lacked virus-neutralizing activity. The protection observed challenges the paradigm whereby circulating antiviral antibodies are required for protection against HIV-1 infection and may serve in designing a human vaccine against HIV-1-AIDS.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • AIDS Vaccines / administration & dosage*
  • AIDS Vaccines / immunology
  • Amino Acid Motifs
  • Amino Acid Sequence
  • Animals
  • Antibody-Dependent Cell Cytotoxicity
  • Binding Sites
  • Female
  • HIV Antibodies / biosynthesis*
  • HIV Antibodies / immunology
  • HIV Envelope Protein gp41 / administration & dosage
  • HIV Envelope Protein gp41 / immunology*
  • HIV Infections / immunology
  • HIV Infections / prevention & control
  • HIV Infections / transmission
  • HIV Seropositivity
  • HIV-1 / immunology*
  • Immunization*
  • Macaca mulatta / immunology*
  • Molecular Sequence Data
  • Peptide Fragments / administration & dosage
  • Peptide Fragments / immunology*
  • Transcytosis
  • Vagina / immunology*
  • Viremia / immunology
  • Viremia / prevention & control
  • Viremia / transmission
  • Virosomes / immunology*
  • gag Gene Products, Human Immunodeficiency Virus / analysis


  • AIDS Vaccines
  • HIV Antibodies
  • HIV Envelope Protein gp41
  • HIV-1 envelope protein gp41 (649-683)
  • Peptide Fragments
  • Virosomes
  • gag Gene Products, Human Immunodeficiency Virus
  • p27 gag protein, Human immunodeficiency virus