PD1-based DNA vaccine amplifies HIV-1 GAG-specific CD8+ T cells in mice

J Clin Invest. 2013 Jun;123(6):2629-42. doi: 10.1172/JCI64704. Epub 2013 May 1.

Abstract

Viral vector-based vaccines that induce protective CD8+ T cell immunity can prevent or control pathogenic SIV infections, but issues of preexisting immunity and safety have impeded their implementation in HIV-1. Here, we report the development of what we believe to be a novel antigen-targeting DNA vaccine strategy that exploits the binding of programmed death-1 (PD1) to its ligands expressed on dendritic cells (DCs) by fusing soluble PD1 with HIV-1 GAG p24 antigen. As compared with non-DC-targeting vaccines, intramuscular immunization via electroporation (EP) of the fusion DNA in mice elicited consistently high frequencies of GAG-specific, broadly reactive, polyfunctional, long-lived, and cytotoxic CD8+ T cells and robust anti-GAG antibody titers. Vaccination conferred remarkable protection against mucosal challenge with vaccinia GAG viruses. Soluble PD1-based vaccination potentiated CD8+ T cell responses by enhancing antigen binding and uptake in DCs and activation in the draining lymph node. It also increased IL-12-producing DCs and engaged antigen cross-presentation when compared with anti-DEC205 antibody-mediated DC targeting. The high frequency of durable and protective GAG-specific CD8+ T cell immunity induced by soluble PD1-based vaccination suggests that PD1-based DNA vaccines could potentially be used against HIV-1 and other pathogens.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • AIDS Vaccines
  • Animals
  • Antigens, Viral / immunology
  • CD8-Positive T-Lymphocytes / immunology*
  • CD8-Positive T-Lymphocytes / virology
  • Cell Line, Tumor
  • Cell Proliferation
  • Cross-Priming
  • Dendritic Cells / immunology
  • Dendritic Cells / metabolism
  • Dendritic Cells / virology
  • Female
  • HEK293 Cells
  • HIV Core Protein p24 / immunology*
  • HIV Infections / prevention & control*
  • HIV-1 / immunology*
  • Humans
  • Interleukin-12 / metabolism
  • Mice
  • Mice, Inbred BALB C
  • Mice, Inbred C57BL
  • Programmed Cell Death 1 Receptor / immunology*
  • Protein Binding
  • Recombinant Fusion Proteins / immunology
  • Vaccination
  • Vaccines, DNA

Substances

  • AIDS Vaccines
  • Antigens, Viral
  • HIV Core Protein p24
  • PDCD1 protein, human
  • Programmed Cell Death 1 Receptor
  • Recombinant Fusion Proteins
  • Vaccines, DNA
  • Interleukin-12