Campylobacter is the leading cause of foodborne diarrhoeal illness in the developed world and consump-tion or handling of contaminated poultry meat is the principal source of infection. Strategies to controlCampylobacter in broilers prior to slaughter are urgently required and are predicted to limit the inci-dence of human campylobacteriosis. Towards this aim, a purified recombinant subunit vaccine basedon the superoxide dismutase (SodB) protein of C. jejuni M1 was developed and tested in White Leghornbirds. Birds were vaccinated on the day of hatch and 14 days later with SodB fused to glutathione S-transferase (GST) or purified GST alone. Birds were challenged with C. jejuni M1 at 28 days of age andcaecal Campylobacter counts determined at weekly intervals. Across three independent trials, the vaccineinduced a statistically significant 1 log10reduction in caecal Campylobacter numbers in vaccinated birdscompared to age-matched GST-vaccinated controls. Significant induction of antigen-specific serum IgYwas detected in all vaccinated birds, however the magnitude and timing of SodB-specific IgY did not cor-relate with lower numbers of C. jejuni. Antibodies from SodB-vaccinated chickens detected the proteinin the periplasm and not membrane fractions or on the bacterial surface, suggesting that the protectionobserved may not be strictly antibody-mediated. SodB may be useful as a constituent of vaccines forcontrol of C. jejuni infection in broiler birds, however modest protection was observed late relative to thelife of broiler birds and further studies are required to potentiate the magnitude and timing of protection.
- Campylobacter jejuni
- Superoxide dismutase