Immunization with alkyl hydroperoxide reductase subunit C reduces Fusobacterium nucleatum load in the intestinal tract

Sci Rep. 2017 Sep 5;7(1):10566. doi: 10.1038/s41598-017-11127-x.

Abstract

Fusobacterium nucleatum (Fn) is an important tumour-associated bacterium in colorectal cancer (CRC). The antioxidant protein alkyl hydroperoxide reductase subunit C (AhpC) can induce strong antibacterial immune response during various pathogen infections. Our study aimed to evaluate the efficacy of Fn-AhpC as a candidate vaccine. In this work, by western blot analysis, we showed that Fn-AhpC recombinant protein could be recognized specifically by antibodies present in the sera of CRC patients; using the mouse Fn-infection model, we observed that systemic prophylactic immunization with AhpC/alum conferred significant protection against infection in 77.3% of mice. In addition, we measured the anti-AhpC antibody level in the sera of CRC patients and found that there was no obvious increase of anti-AhpC antibodies in the early-stage CRC group. Furthermore, we treated Fn with the sera from both immunized mice and CRC patients and found that sera with high anti-AhpC antibodies titre could inhibit Fn growth. In conclusion, our findings support the use of AhpC as a potential vaccine candidate against inhabitation or infection of Fn in the intestinal tract, which could provide a practical strategy for the prevention of CRC associated with Fn infection.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antibodies, Bacterial / immunology
  • Bacterial Load
  • Bacterial Proteins / genetics
  • Bacterial Proteins / immunology*
  • Bacterial Vaccines / immunology*
  • Colorectal Neoplasms / microbiology*
  • Female
  • Fusobacterium / immunology
  • Fusobacterium / pathogenicity
  • Fusobacterium Infections / immunology*
  • Fusobacterium Infections / therapy
  • Humans
  • Intestines / microbiology*
  • Mice
  • Mice, Inbred BALB C
  • Peroxiredoxins / genetics
  • Peroxiredoxins / immunology*

Substances

  • Antibodies, Bacterial
  • Bacterial Proteins
  • Bacterial Vaccines
  • Peroxiredoxins