Divergence of primary cognate B- and T-cell proliferative responses to subcutaneous and intravenous immunization with virus-like particles

Viruses. 2014 Aug 22;6(8):3334-47. doi: 10.3390/v6083334.

Abstract

A major advantage of virus-like particle (VLP) vaccines against HIV is their structural identity to wild-type viruses, ensuring that antigen-specific B-cells encounter the envelope protein in its natural conformation. For the induction of affinity-matured antibodies, the B-cells must also obtain help from T-cells that are restricted by linear epitopes. Using B- and T-cell transgenic mouse models, we compared the efficacy of modified HIV-VLPs delivered by subcutaneous and intravenous immunization to stimulate primary B- and T-cell proliferative responses in different lymphoid organs. VLPs containing an influenza virus hemagglutinin epitope within the HIV-Gag protein induced comparable primary cognate T-cell proliferative responses in the draining lymph node and the spleen, irrespective of the delivery route. In contrast, after subcutaneous immunization with HIV-Gag VLPs containing hen egg lysozyme (HEL) on their surface, the proliferative response of transgenic HEL-specific B-cells was restricted to the draining lymph nodes, while intravenous VLP immunization primarily induced a B-cell proliferative response in the spleen. In vitro co-culture experiments further revealed that the presentation of VLP-associated surface antigens by dendritic cells to cognate B-cells is inefficient. This is consistent with a direct triggering of the B-cell proliferative response by the VLPs and suggests that HIV VLPs may indeed be suitable to directly promote the expansion of B-cells specific for conformational epitopes that are unique to functionally-active Env spikes on the virion. Further investigations are warranted to explore potential differences in the quality and protective potency of HIV-specific antibody responses induced by the two routes.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • AIDS Vaccines / administration & dosage
  • AIDS Vaccines / immunology
  • Administration, Intravenous
  • Animals
  • B-Lymphocytes / immunology*
  • Cell Proliferation
  • Epitopes / genetics
  • Epitopes / immunology
  • Female
  • Hemagglutinin Glycoproteins, Influenza Virus / genetics
  • Hemagglutinin Glycoproteins, Influenza Virus / immunology
  • Injections, Subcutaneous
  • Lymph Nodes / immunology
  • Mice, Inbred BALB C
  • Mice, Inbred C57BL
  • Mice, Transgenic
  • Muramidase / genetics
  • Muramidase / immunology
  • Recombinant Fusion Proteins / genetics
  • Recombinant Fusion Proteins / immunology
  • Spleen / immunology
  • T-Lymphocytes / immunology*
  • Vaccination / methods
  • Vaccines, Virus-Like Particle / administration & dosage*
  • Vaccines, Virus-Like Particle / immunology*
  • gag Gene Products, Human Immunodeficiency Virus / genetics
  • gag Gene Products, Human Immunodeficiency Virus / immunology

Substances

  • AIDS Vaccines
  • Epitopes
  • Hemagglutinin Glycoproteins, Influenza Virus
  • Recombinant Fusion Proteins
  • Vaccines, Virus-Like Particle
  • gag Gene Products, Human Immunodeficiency Virus
  • Muramidase