HIV-1 Gag p17 presented as virus-like particles on the E2 scaffold from Geobacillus stearothermophilus induces sustained humoral and cellular immune responses in the absence of IFNγ production by CD4+ T cells

Virology. 2010 Nov 25;407(2):296-305. doi: 10.1016/j.virol.2010.08.026. Epub 2010 Sep 20.

Abstract

We have constructed stable virus-like particles displaying the HIV-1 Gag(p17) protein as an N-terminal fusion with an engineered protein domain from the Geobacillus stearothermophilus pyruvate dehydrogenase subunit E2. Mice immunized with the Gag(p17)-E2 60-mer scaffold particles mounted a strong and sustained antibody response. Antibodies directed to Gag(p17) were boosted significantly with additional immunizations, while anti-E2 responses reached a plateau. The isotype of the induced antibodies was biased towards IgG1, and the E2-primed CD4+ T cells did not secrete IFNγ. Using transgenic mouse model systems, we demonstrated that CD8+ T cells primed with E2 particles were able to exert lytic activity and produce IFNγ. These results show that the E2 scaffold represents a powerful vaccine delivery system for whole antigenic proteins or polyepitope engineered proteins, evoking antibody production and antigen specific CTL activity even in the absence of IFNγ-producing CD4+ T cells.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • AIDS Vaccines / immunology*
  • Acyltransferases / genetics
  • Acyltransferases / immunology
  • Acyltransferases / metabolism
  • Animals
  • B-Lymphocytes / immunology
  • Bacterial Proteins / genetics
  • Bacterial Proteins / metabolism
  • CD4-Positive T-Lymphocytes / metabolism
  • Female
  • Genetic Vectors*
  • Geobacillus stearothermophilus / enzymology
  • Geobacillus stearothermophilus / genetics
  • Geobacillus stearothermophilus / immunology
  • Geobacillus stearothermophilus / metabolism*
  • HIV Antibodies / blood*
  • HIV-1 / genetics
  • HIV-1 / immunology
  • HIV-1 / metabolism
  • Humans
  • Immunization
  • Interferon-gamma / biosynthesis
  • Lymphocyte Activation / immunology*
  • Mice
  • Mice, Inbred BALB C
  • Mice, Inbred C57BL
  • Peptide Fragments / genetics
  • Peptide Fragments / immunology*
  • Peptide Fragments / metabolism
  • Recombinant Fusion Proteins / genetics
  • Recombinant Fusion Proteins / immunology
  • Recombinant Fusion Proteins / metabolism
  • T-Lymphocytes / immunology
  • Virion / immunology*
  • env Gene Products, Human Immunodeficiency Virus / genetics
  • env Gene Products, Human Immunodeficiency Virus / immunology*
  • env Gene Products, Human Immunodeficiency Virus / metabolism

Substances

  • AIDS Vaccines
  • Bacterial Proteins
  • HIV Antibodies
  • Peptide Fragments
  • Recombinant Fusion Proteins
  • env Gene Products, Human Immunodeficiency Virus
  • p17 gag peptide, human immunodeficiency virus
  • Interferon-gamma
  • Acyltransferases