Production and evaluation of a recombinant chimeric vaccine against clostridium botulinum neurotoxin types C and D

PLoS One. 2013 Jul 31;8(7):e69692. doi: 10.1371/journal.pone.0069692. Print 2013.

Abstract

Bovine botulism is a fatal disease that is caused by botulinum neurotoxins (BoNTs) produced by Clostridium botulinum serotypes C and D and that causes great economic losses, with nearly 100% lethality during outbreaks. It has also been considered a potential source of human food-borne illness in many countries. Vaccination has been reported to be the most effective way to control bovine botulism. However, the commercially available toxoid-based vaccines are difficult and hazardous to produce. Neutralizing antibodies targeted against the C-terminal fragment of the BoNT heavy chain (HC) are known to confer efficient protection against lethal doses of BoNTs. In this study, a novel recombinant chimera, consisting of Escherichia coli heat-labile enterotoxin B subunit (LTB), a strong adjuvant of the humoral immune response, fused to the HC of BoNT serotypes C and D, was produced in E. coli. Mice vaccinated with the chimera containing LTB and an equivalent molar ratio of the chimera without LTB plus aluminum hydroxide (Al(OH)3) developed 2 IU/mL of antitoxins for both serotypes. Guinea pigs immunized with the recombinant chimera with LTB plus Al(OH)3 developed a protective immune response against both BoNT/C (5 IU/mL) and BoNT/D (10 IU/mL), as determined by a mouse neutralization bioassay with pooled sera. The results achieved with guinea pig sera fulfilled the requirements of commercial vaccines for prevention of botulism, as determined by the Brazilian Ministry of Agriculture, Livestock and Food, Supply. The presence of LTB was essential for the development of a strong humoral immune response, as it acted in synergism with Al(OH)3. Thus, the vaccine described in this study is a strong candidate for the control of botulism in cattle.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aluminum Hydroxide / immunology
  • Amino Acid Sequence
  • Animals
  • Antibodies, Bacterial / immunology
  • Antitoxins / immunology
  • Bacterial Toxins / genetics
  • Bacterial Toxins / immunology
  • Bacterial Toxins / metabolism
  • Base Sequence
  • Blotting, Western
  • Botulinum Toxins / genetics
  • Botulinum Toxins / immunology
  • Botulinum Toxins / metabolism
  • Botulism / immunology*
  • Botulism / prevention & control
  • Botulism / veterinary
  • Cattle
  • Clostridium botulinum type C / immunology*
  • Clostridium botulinum type D / immunology*
  • Drug Evaluation
  • Enterotoxins / genetics
  • Enterotoxins / immunology
  • Enterotoxins / metabolism
  • Enzyme-Linked Immunosorbent Assay
  • Escherichia coli Proteins / genetics
  • Escherichia coli Proteins / immunology
  • Escherichia coli Proteins / metabolism
  • Female
  • Guinea Pigs
  • Mice
  • Molecular Sequence Data
  • Recombinant Fusion Proteins / genetics
  • Recombinant Fusion Proteins / immunology
  • Recombinant Fusion Proteins / metabolism
  • Vaccination / methods
  • Vaccines, Synthetic / administration & dosage
  • Vaccines, Synthetic / immunology*
  • Vaccines, Synthetic / standards

Substances

  • Antibodies, Bacterial
  • Antitoxins
  • Bacterial Toxins
  • Enterotoxins
  • Escherichia coli Proteins
  • Recombinant Fusion Proteins
  • Vaccines, Synthetic
  • Aluminum Hydroxide
  • heat-labile enterotoxin, E coli
  • Botulinum Toxins

Grants and funding

CNPq (project 5.05.02.00-0), http://www.cnpq.br/. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.