Effective CD8(+) T cell priming and tumor protection by enterotoxin B subunit-conjugated peptides targeted to dendritic cells

Vaccine. 2009 Aug 20;27(38):5252-8. doi: 10.1016/j.vaccine.2009.06.053. Epub 2009 Jul 2.

Abstract

In our previous studies we have shown that bacterial enterotoxin B subunits are effective vehicles to deliver antigen into the MHC class I processing route. Here we have used the non-toxic Escherichia coli heat labile enterotoxin B subunit (EtxB) conjugated to OVA peptide (EtxB-peptide) to address the impact on induction of specific CD8(+) T cells in vivo. Although incubation of DCs with these EtxB-peptide conjugates as such did not induce DC maturation in vitro MHC class I antigen presentation was much more efficient as compared to peptide alone. Antigen presentation was further enhanced upon DC maturation with the TLR-4 ligand LPS. Injection of matured DCs incubated with EtxB-peptide conjugates lead to strong induction of OVA-specific CD8(+) T lymphocytes and fully prevented the outgrowth of lethal B16 melanoma in wild type mice. Our data demonstrate that bacterial non-toxic B subunit-peptide conjugates are potent vaccine vehicles for induction of protective CD8(+) T cell responses.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antigen Presentation
  • Bacterial Toxins / immunology*
  • CD8-Positive T-Lymphocytes / immunology*
  • Cancer Vaccines / immunology*
  • Cell Line
  • Dendritic Cells / immunology*
  • Enterotoxins / immunology*
  • Escherichia coli Proteins / immunology*
  • Female
  • Genes, MHC Class I
  • Lymphocyte Activation
  • Melanoma, Experimental / immunology
  • Melanoma, Experimental / prevention & control*
  • Mice
  • Mice, Inbred C57BL

Substances

  • Bacterial Toxins
  • Cancer Vaccines
  • Enterotoxins
  • Escherichia coli Proteins
  • heat-labile enterotoxin, E coli