Small molecule mimetics of an HIV-1 gp41 fusion intermediate as vaccine leads

J Biol Chem. 2010 Dec 24;285(52):40604-11. doi: 10.1074/jbc.M110.172197. Epub 2010 Oct 13.

Abstract

We describe here a novel platform technology for the discovery of small molecule mimetics of conformational epitopes on protein antigens. As a model system, we selected mimetics of a conserved hydrophobic pocket within the N-heptad repeat region of the HIV-1 envelope protein, gp41. The human monoclonal antibody, D5, binds to this target and exhibits broadly neutralizing activity against HIV-1. We exploited the antigen-binding property of D5 to select complementary small molecules using a high throughput screen of a diverse chemical collection. The resulting small molecule leads were rendered immunogenic by linking them to a carrier protein and were shown to elicit N-heptad repeat-binding antibodies in a fraction of immunized mice. Plasma from HIV-1-infected subjects shown previously to contain broadly neutralizing antibodies was found to contain antibodies capable of binding to haptens represented in the benzylpiperidine leads identified as a result of the high throughput screen, further validating these molecules as vaccine leads. Our results suggest a new paradigm for vaccine discovery using a medicinal chemistry approach to identify lead molecules that, when optimized, could become vaccine candidates for infectious diseases that have been refractory to conventional vaccine development.

MeSH terms

  • AIDS Vaccines / immunology*
  • AIDS Vaccines / pharmacology
  • Animals
  • Antibodies, Neutralizing / blood
  • Antibodies, Neutralizing / immunology*
  • Antibodies, Viral / blood
  • Antibodies, Viral / immunology*
  • Female
  • HIV Envelope Protein gp41 / immunology*
  • HIV Infections / blood
  • HIV Infections / immunology*
  • HIV Infections / prevention & control
  • HIV-1 / immunology*
  • Haptens / immunology
  • Haptens / pharmacology
  • Humans
  • Mice
  • Mice, Inbred BALB C
  • Peptidomimetics / immunology*
  • Peptidomimetics / pharmacology

Substances

  • AIDS Vaccines
  • Antibodies, Neutralizing
  • Antibodies, Viral
  • HIV Envelope Protein gp41
  • Haptens
  • Peptidomimetics
  • gp41 protein, Human immunodeficiency virus 1